Publications by authors named "Boxiong Shen"

37 Publications

Enhanced oxidative removal of NO by UV/in situ Fenton: Factors, kinetics and simulation.

Sci Total Environ 2021 Jul 3;778:146202. Epub 2021 Mar 3.

School of Chemical Engineering & Technology, Hebei University of Technology, Tianjin 300130, PR China. Electronic address:

A series of experiments on the oxidative removal of NO from flue gas using a novel in situ Fenton (IF) system was performed in the presence of ultraviolet light (UV). The comparison tests revealed that the in situ Fenton system facilitated by UV (UV/IF) has a better oxidation ability of NO than that of the IF system due to the photochemical effect on the generation of oxidative species like (OH). Both of the aforementioned oxidation efficiencies were higher than that of the conventional Fenton system (CF) depending on the premix of Fe and HO solutions, which attribute to the improvement of (OH) yield and valid utilization with continuous addition of fresh reagents and UV radiation. In follow-up experiments, the effects of UV power, gas flow rate, reagent temperature, Fe/HO molar ratio, initial pH, initial concentration of NO and SO and volume fraction O and CO on the oxidative removal of NO by UV/IF method were investigated respectively. Moreover, the results of kinetic analysis indicated that NO oxidation was confirmed to have a pseudo-first-order kinetics pattern. The rate constants decreased slightly with increasing liquid temperature, and then the apparent activation energy of NO oxidation reactions in the UV/IF system was calculated as -5.62 kJ/mol by the Arrhenius equation. Furthermore, the reaction mechanism and application prospects concerning NO oxidative removal by using the UV/IF system was speculated in brief. Finally, the computational fluid dynamics (CFD) simulations revealed that the improvement of axial and radial gas hold-up would enhance the gas-liquid contact and accelerate the oxidation reactions on the interface. In addition to reasonable control of process parameters, the optimization of reactor interior structure needs to be carried out via CFD simulation and experimental validation in future research, both are favourable to promote the NO oxidation efficiency and large-scale development of this technology.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146202DOI Listing
July 2021

Exposure characteristics and risk assessment of VOCs from Chinese residential cooking.

J Environ Manage 2021 Jul 22;289:112535. Epub 2021 Apr 22.

School of Chemical Engineering, Hebei University of Technology, Tianjin, 300401, China; School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China. Electronic address:

In comparison with various restaurant cuisines, common cooking methods are more represented in residential cooking. Rather than the exhaust pipe or the ambient environment in the cooking room, the respiration zone better reflects the health risks for operators. In this study, the concentrations of total volatile organic compound (TVOC) released from six typical cooking methods were monitored online in the respiratory zone, and the VOCs were analysed by GC-MS. The results demonstrated that the intensities of exposure to TVOC for the different cooking methods decreased as follows: stir-frying (3.809 mg/m) > quick-frying (2.724 mg/m) > deep-frying (2.465 mg/m) > boiling (1.161 mg/m)≈stewing (1.149 mg/m) > limit in China (0.600 mg/m) > steaming (0.440 mg/m). The intense ventilation mode of the ventilator reduced exposure to TVOC by 45-63% relative to the medium mode. Eleven types of VOCs (approximately 200 compounds) were found in Chinese residential cooking fumes, and the predominant contaminants were aldehydes, followed by alkanes, unsaturated aldehydes, alcohols and alkenes. The mass percentage of aromatic hydrocarbons in all VOCs emitted from Chinese residential cooking was only 1%, while the value was 17-48% for commercial restaurants. The results of a health risk assessment revealed that the total potential carcinogenic risk level for VOCs released by six residential cooking methods decreased as follows: deep-frying (5.75) > stir-frying (3.95) > quick-frying (2.94) > stewing (1.99) > boiling (1.73) > steaming (1.48). Chinese residential cooking, and especially deep frying, has potential health impacts for the operator.
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http://dx.doi.org/10.1016/j.jenvman.2021.112535DOI Listing
July 2021

Superhydrophobic-superoleophilic biochar-based foam for high-efficiency and repeatable oil-water separation.

Sci Total Environ 2021 Aug 17;780:146517. Epub 2021 Mar 17.

Tianjin Eco-City Environmental Protection Limited Company, Tianjin 300467, China.

Leakage accidents occurring during oil production and transportation are currently one of the most serious environmental problems worldwide. Developing efficient and environmentally friendly oil-water separation methods is the key to solve this problem. In this work, a facile method to fabricate a high-performance oil absorbent through the loading of ball-milled biochar (BMBC) and octadecylamine on the skeleton of melamine foam (MF) is reported. The resulting ball-milled biochar-based MF ([email protected]) displayed a complex three-dimensional porous structure. The BM biochar on the surface of [email protected] forms nano/μm-scale folds, which reduced the surface energy of [email protected] after grafted octadecylamine. These structures resulted in the conversion of the hydrophilic surface of MF to hydrophobic surface. These characteristics made the modified foam an excellent oil absorbent with a high oil absorption capacity (43-155 times its own weight) and extraordinary recyclability. Furthermore, the [email protected] could maintain high hydrophobicity and adsorption stability in a wide pH range (from 1 to 11). More importantly, BM biochar is a cheap and readily available material to make [email protected] possible for large-scale production. Therefore, this work provides an effective way for low-cost, environmentally friendly, and large-scale production of superhydrophobic adsorbents for oil-water separation.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146517DOI Listing
August 2021

Influence of thermal assistance on the biodegradation of organics during food waste bio-drying: Microbial stimulation and energy assessment.

Chemosphere 2021 Jun 6;272:129875. Epub 2021 Feb 6.

School of Environmental Science & Technology, Dalian University of Technology, Dalian, 116024, Liaoning, China. Electronic address:

Recently, bio-drying was highlighted in the drying pretreatment of high-moisture organic wastes for their energy recovery. In this study, to investigate the influences of thermal assistance on microbial stimulation and energy utilization in organic degradation, thermally assisted bio-drying (TB) was conducted on food waste (FW) and was compared with conventional bio-drying (CB) and thermal drying (TD). As expected, more water was removed in TB, which exhibited no lag phenomenon and intensified microbial activity. Corresponding with the stimulated enzyme activity, more readily degradable carbohydrates, lipids and lignocellulose were decomposed in TB than those in CB, and lipid degradation generated a significant proportion of the total bio-heat generated (43.13%-45.83%). Furthermore, according to the microbial analysis (qPCR and 16S rRNA gene sequencing), Bacillus was found to be the dominant genus involved in the degradation of organics during TB and CB. In the initial phase, rather than Weissella, as in CB, Ureibacillus was notable in TB for the degradation of readily degradable substrates. In the late phase, Pseudoxanthomonas and Saccharomonospora were enriched for degrading lignocellulose. In addition, heat balance and life-cycle energy assessment demonstrated that a small amount of thermal heat (11.96%) upgraded bio-drying with high energy efficiency. Compared with the CB and TD processes, the TB trial consumed less thermal energy (0.58 MJ/kg HO) and achieved a higher energy output/input ratio (3.64). This research suggests that thermal assistance is a promising approach to enhancing FW bio-drying, which exhibits efficient drying performance and great potential for energy recovery.
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http://dx.doi.org/10.1016/j.chemosphere.2021.129875DOI Listing
June 2021

Chlorella vulgaris cultivation in simulated wastewater for the biomass production, nutrients removal and CO fixation simultaneously.

J Environ Manage 2021 Apr 6;284:112070. Epub 2021 Feb 6.

Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, PR China; School of Civil and Transportation Engineering, Hebei University of Technology, Tianjin, 300401, PR China. Electronic address:

Chlorella vulgaris (C. vulgaris) was promising microalgae to simultaneously achieve biomass production, carbon dioxide (CO) fixation, nutrients removal and proteins production especially under different conditions of CO gas and wastewaters. Results presented that maximal specific growth rate of C. vulgaris was 0.21-0.35 d and 0.33-0.43 d at 0.038% and 10% CO respectively, and corresponding maximal CO fixation rate was attended with 4.51-14.26 and 56.26-85.72 mg CO·L·d. C. vulgaris showed good wastewater removal efficiency of nitrogen and phosphorus at 10% CO with 96.12%-99.61% removal rates. Nitrogen fixation amount achieved 41.86 mg L when the initial NHCl concentration was set at 60 mg L at 10% CO. Improved total protein (25.01-365.49 mg) and amino acids (24.56-196.44 mg) contents of C. vulgaris biomass was observed with the increasing of added CO and ammonium concentrations. Moreover, the developed kinetic function of C. vulgaris growth depends on both phosphorus quota and nitrogen quota with correlation coefficient (R) ranged from 0.68 to 0.97. Computed maximal consumed nutrients concentrations (ΔC) based on Logistic function are positively related to initial NH-N concentrations, which indicated that adding ammonium could stimulate the utilization of both phosphorus and nitrogen.
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http://dx.doi.org/10.1016/j.jenvman.2021.112070DOI Listing
April 2021

Elucidating the pyrolysis reaction mechanism of Calotropis procera and analysis of pyrolysis products to evaluate its potential for bioenergy and chemicals.

Bioresour Technol 2021 Feb 15;322:124545. Epub 2020 Dec 15.

Government College University Faisalabad, Faisalabad 38000, Pakistan. Electronic address:

The present study was focused on evaluating the bioenergy potential of waste biomass of desert plant Calotropis procera. The biomass was pyrolyzed at four heating rates including 10 °Cmin, 20 °Cmin, 40 °Cmin, and 80 °Cmin. The pyrolysis reaction kinetics and thermodynamics parameters were assessed using isoconversional models namely Kissenger-Akahira-Sunose, Flynn-Wall-Ozawa, and Starink. Major pyrolysis reaction occurred between 200 and 450 °C at the conversion points (α) ranging from 0.2 to 0.6 while their corresponding reaction parameters including activation energy, enthalpy change, Gibb's free energy and pre-exponential factors were ranged from 165 to 207 kJ mol, 169-200 kJ mol, 90-42 kJ mol, and 10-10 s, respectively. The narrow range of pre-exponential factors indicated a uniform pyrolysis, while lower differences between enthalpy change and activation energies indicated that reactions were thermodynamically favorable. The evolved gases were dominated by propanoic acid, 3-hydroxy-, hydrazide, hydrazinecarboxamide and carbohydrazide followed by amines/amides, alcohols, acids, aldehydes/ketones, and esters.
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http://dx.doi.org/10.1016/j.biortech.2020.124545DOI Listing
February 2021

Review on the NO removal from flue gas by oxidation methods.

J Environ Sci (China) 2021 Mar 21;101:49-71. Epub 2020 Aug 21.

TUS Environmental Science and Technology Development Co. Ltd., Yichang 443000, China.

Due to the increasingly strict emission standards of NOx on various industries, many traditional flue gas treatment methods have been gradually improved. Except for selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) methods to remove NOx from flue gas, theoxidation method is paying more attention to NOx removal now because of the potential to simultaneously remove multiple pollutants from flue gas. This paper summarizes the efficiency, reaction conditions, effect factors, and reaction mechanism of NO oxidation from the aspects of liquid-phase oxidation, gas-phase oxidation, plasma technology, and catalytic oxidation. The effects of free radicals and active components of catalysts on NO oxidation and the combination of various oxidation methods are discussed in detail. The advantages and disadvantages of different oxidation methods are summarized, and the suggestions for future research on NO oxidation are put forward at the end. The review on the NO removal by oxidation methods can provide new ideas for future studies on the NO removal from flue gas.
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http://dx.doi.org/10.1016/j.jes.2020.08.004DOI Listing
March 2021

Enhanced hydrogen production from catalytic biomass gasification with in-situ CO capture.

Environ Pollut 2020 Dec 8;267:115487. Epub 2020 Sep 8.

School of Energy and Environmental Engineering, Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, Hebei University of Technology, China; School of Chemistry and Chemical Engineering, Queens University Belfast, Belfast, Northern Ireland, BT7 1NN, United Kingdom. Electronic address:

In order to cope with the global energy crisis and environmental pollution problems, there are urgent needs for clean energy such as biomass-derived hydrogen. CaO is effective to promote hydrogen production from biomass gasification due to its high capacity of in-situ CO capture. In this work, a two-stage fixed bed reactor was used to produce hydrogen by catalytic conversion of biomass with and without in-situ CO capture. In addition, three Ni loadings (5 wt%, 10 wt%, and 20 wt%) supported by AlO and sol-gel CaO have been prepared and tested. The BET analysis shows the surface area of the catalysts increases first and then decreases with the increase of Ni loading. Results from high-resolution transmission electron microscopy (HRTEM) images reveals that NiO particles are well distributed over the porous CaO. The X-ray diffraction (XRD) analysis indicates the NiO nanocrystalline size is increased with increasing Ni loading on Ni/AlO, and the most homogeneous dispersion was shown by 10 wt% Ni/CaO. Around 666 mgCO/gCaO of CO adsorption capacity and 850 min stability were obtained using the sol-gel CaO sorbent. Compared to the reference Ni/AlO catalysts, the resistance of carbon deposition on the Ni/CaO results in a lower coke deposition, which is attributed to the basicity of the catalysts. In addition, the increase of loading promotes the decomposition of biomass-derived oxygenated compounds. Much more hydrogen is obtained using the Ni/CaO catalysts compared with Ni/AlO due to in-situ CO capture. However, the sintering and particle agglomeration using the 20 wt% Ni-catalyst might be responsible for the reduction of hydrogen production. The highest H concentration of 19.32 vol% at 424 °C was obtained when the 10 wt% Ni/CaO catalyst was used.
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http://dx.doi.org/10.1016/j.envpol.2020.115487DOI Listing
December 2020

Role of impurity components and pollutant removal processes in catalytic oxidation of o-xylene from simulated coal-fired flue gas.

Sci Total Environ 2021 Apr 8;764:142805. Epub 2020 Oct 8.

Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba, Sendai 980-8579, Japan.

Volatile organic compounds (VOCs) emitted from coal-fired flue gas of thermal power plants have reached unprecedented levels due to lack of understanding of reaction mechanisms under industrial settings. Herein, inhibition mechanisms for catalytic oxidation of o-xylene in simulated coal-fired flue gas are elucidated with in-situ and ex-situ spectroscopic techniques considering the presence of impurity components (NO, NH, SO, HO). MnCe oxide catalysts prepared at Mn: Ce mass ratios of 6:4 are demonstrated to promote 87% o-xylene oxidation at 250 °C under gas hourly space velocities of 60,000 h. Reaction intermediates on the catalyst surface are revealed to be o-benzoquinones, benzoates, and formate and they were stably formed under O/N atmospheres. When either NO or NH was introduced into the simulated flue gas, the formed species shifted toward formate in minutes, which indicated that changes in catalyst surface chemistry are directly related to impurity components. Presence of NH in the simulated flue gas inhibited o-xylene oxidation by reducing Mn and lowering Brønsted acidity of the catalyst. Impurity components associated with pollutant removal processes (Hg oxidation and selective catalytic reduction of NO) lowered o-xylene removal efficiency. Presence of o-xylene in the flue gas had little effect on the efficiency of pollutant removal processes. Layered catalytic beds located downstream from Hg/NO pollutant removal processes are proposed to lower VOC emissions from coal-fired flue gases of thermal power plants in industrial settings.
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http://dx.doi.org/10.1016/j.scitotenv.2020.142805DOI Listing
April 2021

Recycling of spent alkaline Zn-Mn batteries directly: Combination with TiO to construct a novel Z-scheme photocatalytic system.

J Hazard Mater 2020 Dec 17;400:123236. Epub 2020 Jun 17.

Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 611731, PR China.

Recycling of spent alkaline Zn-Mn batteries (S-AZMB) has always been a focus of attention in environmental and energy fields. However, the current research mostly concentrated in the recovery of purified materials, and ignores the direct reuse of S-AZMB. Herein, we propose a new concept for the first time that unpurified S-AZMB can be used as raw materials for preparation of Z-scheme photocatalytic system in combination with TiO. A series of characterizations and experiments confirm that the combination with S-AZMB not only extends the response of TiO to visible light, but also significantly enhances the separation ability of photogenerated electron-hole pairs. In the toluene removal experiment, the degradation kinetic rate of Z-scheme [email protected] photocatalyst reaches 21.0 and 10.5 times than that of TiO and S-AZMB, respectively. More notably, this S-AZMB based Z-scheme photocatalyst can maintain structural and photocatalytic performance stability in cyclic catalytic reactions. We believe that this work not only expands the research concept of recycling S-AZMB, but also provides a new idea for designing highly efficient Z-scheme photocatalysts.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123236DOI Listing
December 2020

Effects of system parameters and residual ions on the oxidation removal of NO by Fenton method.

Environ Sci Pollut Res Int 2021 Jan 8;28(3):2959-2971. Epub 2020 Sep 8.

Xi'an Thermal Engineering Institute, Xi'an, 710032, People's Republic of China.

In the present work, the effects of relevant system parameters on the oxidation removal of NO using the Fenton method were discussed in detail. Moreover, the impacts of ions remaining in the coal-fired process on the NO oxidation efficiency were investigated specifically. The experimental results showed that the oxidation efficiency of NO decreased with the increase of gas flow rate, reagent temperature, and CO volume fraction in the evaluated range, while it increased first and then decreased with the increase of gas temperature, NO initial concentration, O volume fraction, initial pH of reagent, and Fe/HO molar ratio. In addition, the corresponding impact mechanism of the system parameters was discussed respectively. Although the SO showed a competitive effect on the utilization of oxidative radicals, the Fenton system also showed an ability for simultaneous removal of NO and SO. Furthermore, the results indicated that the NO oxidation efficiency would be influenced by the residual ions, such as Ca, Mg, Na, SO, and Cl. The presence of the mentioned ions showed an inhibiting effect on the oxidation removal of NO in the first few minutes, while the NO oxidation efficiency would be enhanced in the bulk stage of the tests. The positive effect trended to be more obvious with the decline of the ion dosage. Subsequently, the influence mechanism of the aforesaid residual cations and anions was supposed and proposed preliminarily.
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http://dx.doi.org/10.1007/s11356-020-10187-3DOI Listing
January 2021

Emission control strategies of hazardous trace elements from coal-fired power plants in China.

J Environ Sci (China) 2020 Jul 9;93:66-90. Epub 2020 Mar 9.

School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy Utilization and Pollution Control, Hebei University of Technology, Tianjin, China.

China's energy dependents on coal due to the abundance and low cost of coal. Coal provides a secure and stable energy source in China. Over-dependence on coal results in the emission of Hazardous Trace Elements (HTEs) including selenium (Se), mercury (Hg), lead (Pb), arsenic (As), etc., from Coal-Fired Power Plants (CFPPs), which are the major toxic air pollutants causing widespread concern. For this reason, it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions. The study herein reviews various techniques applied in China for the selected HTEs emission control, including the technical, institutional, policy, and regulatory aspects. The specific areas covered in this study include health effects, future coal production and consumption, the current situation of HTEs in Chinese coal, the chemistry of selected HTEs, control techniques, policies, and action plans safeguarding the emission control. The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development. The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China. Future research should focus on the simultaneous removal of HTEs, PM, SOx, and NOx in the complex flue gas.
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http://dx.doi.org/10.1016/j.jes.2020.02.025DOI Listing
July 2020

Enhanced photocatalytic degradation of xylene by blackening TiO nanoparticles with high dispersion of CuO.

J Hazard Mater 2020 Jun 1;391:121642. Epub 2020 Feb 1.

School of Energy and Environmental Engineering, Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, Hebei University of Technology, China.

To enhance the photocatalytic activity of TiO, a new preparation method has been proposed to synthesize the catalysts by introducing Cu-MOF as a precursor and performing a blackening process via a mixture with NaBH for TiO nanoparticles (CuO-TiO(mb)). The results showed that the removal efficiency of xylene under ultraviolet and visible light over CuO-TiO(mb) was 3.45 times higher than that of the catalysts prepared by impregnation of CuO on the surfaces of TiO (CuO-TiO(d)) and 12.12 times higher than that of pure TiO nanoparticles. Analyses by the X-ray diffraction, scanning electron microscopy, and transmission electron microscopy indicated that the introduction of Cu-MOF as a precursor on the surface of the catalyst resulted in CuO-TiO(mb) presenting a lower grain size compared with TiO nanoparticles and CuO-TiO(d). The results of X-ray photoelectron spectroscopy, diffuse reflectance spectrum and photoluminescence indicated that blackening process narrowed the bind gap width and shortened the band gap from 2.95 eV to 1.32 eV, introduced the coexistence of Ti, Ti, Cu and Cu in CuO-TiO(mb) decreased the recombination rate of e-h, which greatly improved the light response of CuO-TiO(mb) under ultraviolet and visible light, resulting in the benefit to the photocatalytic reaction.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121642DOI Listing
June 2020

Biochar/iron (BC/Fe) composites for soil and groundwater remediation: Synthesis, applications, and mechanisms.

Chemosphere 2020 May 18;246:125609. Epub 2019 Dec 18.

Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China. Electronic address:

Biochar/iron (BC/Fe) composites, such as nano zero-valent iron (nZVI)/BC, iron sulfide/BC, and iron oxide/BC, have been developed and applied to deal with various contaminants owing to their excellent physicochemical properties. This work summarizes the progress in the preparation of BC/Fe composites, the properties and applications of BC/Fe, and the mechanism of the synergistic effect between Fe and BC in the composites. Various methods, including pyrolysis, hydrothermal carbonization, fractional precipitation, and ball milling, have been used to synthesize BC/Fe composites. In addition, the introduction of stabilizers, such as carboxymethyl cellulose (CMC), in the fractional precipitation process further prevents the agglomeration of Fe particles, which enhances the stability and fluidity of the resultant composites to facilitate the application of the composites in soil and water remediation. The application of BC/Fe composites in water and soil remediation is discussed in three aspects based on the interaction mechanisms, namely adsorption, reduction, and oxidation. Overall, the composites showed the synergistic effect of BC and Fe owing to the combination of the specific properties of Fe, such as reduction, catalysis, and magnetism, which can enhance the properties of BC with a larger surface area, abundant functional groups, and increased electron transfer efficiency. This review systemically summarizes the recent developments in BC/Fe composites to maximize the efficiency of BC/Fe application in soil and groundwater remediation. Key challenges and further research needs are also suggested.
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http://dx.doi.org/10.1016/j.chemosphere.2019.125609DOI Listing
May 2020

The emission characteristic of VOCs and the toxicity of BTEX from different mosquito-repellent incenses.

J Hazard Mater 2020 02 12;384:121428. Epub 2019 Oct 12.

School of Energy and Environmental Engineering, Tianjin Key Laboratory of Energy Utilization and Pollutant Control, Hebei University of Technology, Tianjin 300401, China.

Three types of mosquito-repellent incenses including disc, electric liquid and electric mat, were selected to investigate the emission of volatile organic compounds in the respiratory zone during the burning. VOCs were analyzed by GC-MS. Results showed that the average concentration of TVOCs released by using the disc, electric liquid and electric mat mosquito repellent incense types were 7.760 ± 4.724, 3.122 ± 0.866 and 1.192 ± 0.062 mg/m, respectively. The TVOCs pollution level produced during the burning of different mosquito-repellent incense types was ranked in the order: disc > electric liquid > electric mat. The concentration of TVOCs produced by Q-liquid, L-liquid, Q-disc and L-disc mosquito-repellent incense types could cause discomfort to the human body. Other types of mosquito-repellent incense induced multiple synergistic effects on human response. About 230 kinds of VOCs including 14 types of VOCs, were found in the smoke of mosquito-repellent incense. The number and content of alkanes was the highest, followed by aromatic hydrocarbons and esters. The level of non-carcinogenic health risk presented by exposure to BTEX (toluene, xylene and ethylbenzene) was acceptable. The chronic daily intake of VOCs decreased with age for both males and females, with male exposure being higher than that of the female, except for children.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121428DOI Listing
February 2020

Thiol-modified biochar synthesized by a facile ball-milling method for enhanced sorption of inorganic Hg and organic CHHg

J Hazard Mater 2020 02 30;384:121357. Epub 2019 Sep 30.

Tianjin Key Laboratory of Clean Energy and pollution control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China. Electronic address:

Modification of thiol on biochar often demands complex synthetic procedures and chemicals. In this work, a simple and environment friendly thiol-modified biochar (BMS-biochar) was successfully synthesized by ball milling pristine biochar with 3-mercaptopropyltrimethoxysilane (3-MPTS). The resultant BMS-biochar was characterized and tested for aqueous inorganic Hg and organic CHHg removal. Characterization results showed that 3-MPTS was loaded on the surface of biochar through oxygen-containing functional groups (i.e., OH and CO) and π-π bond. Ball milling method improved the properties of BMS-biochar, namely, more efficient SH load, a larger surface area, more functional groups, more negatively charged surface, which resulted in higher removal efficiency of Hg and CHHg (320.1 mg/g for Hg and 104.9 mg/g for CHHg) compared to the pristine biochar (105.7 mg/g for Hg and 8.21 mg/g for CHHg) and thiol-modified biochar through chemical impregnation (CIS-biochar) (175.6 mg/g for Hg and 58.0 mg/g for CHHg). Ball milling increased the sorption capacities of Hg and CHHg through surface adsorption, electrostatic attraction, ligand exchange, and surface complexation. Modeling results suggested that the surface diffusion was the rate-limiting adsorption step for BMS-biochar. This work gave prominence to the potential of ball milling for the preparation of thiol-modified biochar to remove mercury especially organic CHHg by adsorption.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121357DOI Listing
February 2020

Application of biochar and its composites in catalysis.

Chemosphere 2020 Feb 23;240:124842. Epub 2019 Sep 23.

Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China. Electronic address:

With a wide range of raw materials, low cost and large specific surface area, biochar has been widely used in environmental remediation. However, the biochar has a saturated adsorption capacity when it is used as a pollutant adsorbent. Recent efforts have been made to prepare biochar and biochar-based catalysts with enhanced catalytic properties to expand their potential applications. The environmental persistent free radicals (EPFRs) of biochar could react with O to induce hydroxyl radicals (•OH) without the addition of oxidants. When oxidants were added, biochar and biochar-based catalysts could activate them to generate •OH and sulfate radicals (SO•), respectively. Moreover, biochar could act as an electron acceptor to improve the photodegradation capacity of catalysts. With reference to the information regarding biochar and biochar-based catalysts, this work provides a critical review on recent research development as follows: 1) the preparations of various types of biochar and biochar-based catalysts are summarized; 2) the effects of the synthetic conditions and transition metals on the catalytic activity of biochar-based catalysts are discussed; (3) methods for characterizing the active sites of the biochar-based catalysts are described; and (4) the environmental applications of biochar and biochar-based catalysts are discussed with regards to three aspects based on the interaction mechanisms, namely, oxidation, reduction, and photocatalysis. The synthesis conditions and loading of metal/metal-free catalyst are key parameters controlling the catalysis activity of biochar and biochar-based catalysts. This review provides new insights into the application of biochar in catalysis. Key challenges and further research directions are proposed as well.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124842DOI Listing
February 2020

MIL-100(Fe) supported Mn-based catalyst and its behavior in Hg removal from flue gas.

J Hazard Mater 2020 01 13;381:121003. Epub 2019 Aug 13.

School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, China; Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, China.

A novel magnetic composite catalyst of MnOx loaded on MIL-100(Fe) was prepared for the removal of Hg from flue gas, via incipient wetness impregnation followed with calcination at 300 °C. The MIL-100(Fe) supported catalyst showed greater capacity of Hg adsorption and oxidation than FeO supported catalyst at all test temperatures, showing Hg removal efficiency of 77.4% at 250 °C with high GHSV of 18,000 h. Besides the merit of high BET surface area and developed porous, the ultra-highly dispersed and homogeneous Fe sites on MIL(Fe) significantly promoted Hg adsorption and oxidation via the synergy effect with MnOx. Furthermore, the catalyst exhibited magnetic property, which allowed easy separation of the catalyst from fly ash with a recovery of 104%. SO, HO and NH in flue gas were proved inhibited Hg removal via different mechanisms. SO and HO competed and desorbed Hg on the surface of catalyst, while NH was more likely to compete adsorption sites with Hg.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121003DOI Listing
January 2020

Review of biochar for the management of contaminated soil: Preparation, application and prospect.

Sci Total Environ 2019 Apr 27;659:473-490. Epub 2018 Dec 27.

School of Chemistry and Chemical Engineering, Queen's University Belfast, Northern Ireland BT7 1NN, United Kingdom.

As a multi-beneficial amendment, biochar is reasonable and reliable to be employed as an amendment to implement soil remediation. An overview on the manufacture, applications for contaminated soil restoration and revegetation, as well as recommended aspects for future work has been accomplished. One of the objectives of this work presented herein was to determine the effect of feedstock and preparation conditions such as pyrolysis temperature, retention time, gas flow rate, additives on the biochar characteristics and application potentials. Besides, relevant modification or activation technologies have been discussed for the improvement of the biochar functions. The application of biochar could adjust the soil structure (surface area, pore size and distribution etc.), improve the soil physicochemical properties (pH, cation exchange capacity, water retention capacity etc.) and enhance the uptake of soil nutrients for plant growth; In addition, it also can be used to adsorb various contaminants (heavy metals, organic matters), modify the habit and function of microorganism and mitigate climate problem by changing the bioavailability of elements (C, N, K etc.) in soil. These results also provided the possibility to expend the application of biochar to modify the degraded soils in the saline-alkali soil and industrial regions, further increase the usable area of cultivated land. The future research directions could be suggested as long-term field trials, the evaluation of environmental risk and the optimization of biochar production. Moreover, the relevant mechanisms should be adequately considered for maximizing the all-around efficiency of biochar amendments.
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http://dx.doi.org/10.1016/j.scitotenv.2018.12.400DOI Listing
April 2019

Ball-milled biochar for alternative carbon electrode.

Environ Sci Pollut Res Int 2019 May 3;26(14):14693-14702. Epub 2019 Apr 3.

Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Ministry of Agriculture/Tianjin Key Laboratory of Agro-environment and Safe-product, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China.

Ball-milled biochars (BM-biochars) were produced through ball milling of pristine biochars derived from different biomass at three pyrolysis temperatures (300, 450, and 600 °C). The results of scanning electron microscopic (SEM), surface area, hydrodynamic diameter test, and Fourier transform infrared spectroscopy (FTIR) revealed that BM-biochars had smaller particle size (140-250 nm compared to 0.5-1 mm for unmilled biochar), greater stability, and more oxygen-containing functional groups (2.2-4.4 mmol/g compared to 0.8-2.9 for unmilled biochar) than the pristine biochars. With these changes, all the BM-biochar-modified glassy carbon electrodes (BM-biochar/GCEs) exhibited prominent electrochemical properties (e.g., ΔE of 119-254 mV compared to 850 mV for bare GCE). Cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) show that ball-milled 600 °C biochar/GCE (BMBB600/GCE and BMBG600/GCE) had the smallest peak-to-peak separation (ΔE = 119 and 132 mV, respectively), series resistance (R = 88.7 and 89.5 Ω, respectively), and charge transfer resistance (R = 1224 and 1382 Ω, respectively), implying its best electrocatalytic activity for the reduction of Fe(CN). It is supposed that the special structure (i.e., internal surface area, pore volume, oxygen-containing functional groups, and graphitic structure) facilitates the electron transfer and reduces interface resistance. Economic cost of BM-biochar/GCE was 1.97 × 10 USD/cm, much lower than that of a "low-cost platinum electrode" (0.03 USD/cm). The results indicate potential application of the novel BM-biochar for low cost and high efficient electrodes. Graphical abstract.
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http://dx.doi.org/10.1007/s11356-019-04899-4DOI Listing
May 2019

The emission of PM in respiratory zone from Chinese family cooking and its health effect.

Sci Total Environ 2019 Mar 30;654:671-677. Epub 2018 Oct 30.

School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China.

To investigate the PM emission in the direct exposed area from Chinese family cooking, eleven kinds of Chinese ordinary family cooking dishes were designed including frying, quick-frying, stewing, deep-frying, boiling and steaming according to the results of questionnaire survey. The results showed that the intensity sequence for PM emissions decreased as follows in general: deep-frying (0.709-2.731 mg/m) > stir-frying (0.700-0.958 mg/m) > stewing (~0.573 mg/m) > quick-frying (0.140-0.433 mg/m) > boiling (0.004-0.247 mg/m) > steaming (0.011-0.088 mg/m), most of them exceeded the national indoor air standard. The average concentration of PM in the direct respiratory zone from family cooking was determined to be 0.599 mg/m, which was about 8 times higher than the national indoor air standard of China and lower than that from commercial restaurants. The annual PM inhalation exposure in the direct exposed area from family cooking for male and female was 346.30 mg/year and 309.59 mg/year, respectively. Although the annual PM inhalation exposure of male operators in general ordinary family cooking was about 11.8% higher than that of females, the pregnant women, children and the elderly are not encouraged to prepare ordinary family cooking for a long time due to their sensitive to PM emission. Selecting ventilator with high wind speed can reduce PM emission more than 65% when compared to medium wind speed. Improvement of ventilator wind speed is considered to be an effect way to reduce PM emission for cooking.
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http://dx.doi.org/10.1016/j.scitotenv.2018.10.397DOI Listing
March 2019

Development of a novel chem-bio hybrid process using biochar supported nanoscale iron sulfide composite and Corynebacterium variabile HRJ4 for enhanced trichloroethylene dechlorination.

Water Res 2018 12 29;147:132-141. Epub 2018 Sep 29.

Department of Renewable Resources, University of Alberta, Edmonton, Alberta, T6G 2G7, Canada. Electronic address:

A sequential chem-bio hybrid process was developed using a novel biochar supported carboxymethyl cellulose-stabilized nanoscale iron sulfide ([email protected]) as a chemical remover and Corynebacterium variabile HRJ4 as a biological agent for trichloroethylene (TCE) degradation. Compared with CMC-FeS, [email protected], bare FeS and biochar600, the [email protected] composite displayed better physiochemical properties (smaller hydrodynamic diameter and higher stability) and demonstrated excellent removal capacity for TCE from aqueous phase. A facultative bacterial strain, Corynebacterium variabile HRJ4, growing well in the presence of [email protected] (added up to 0.25 g L), further enhanced TCE removal after chemical treatment. The dechlorination pathway proposed based on the gas chromatography-mass spectrometry (GC-MS) analysis revealed that TCE was dechlorinated to cis-1,2-dichloroethene (cis-DCE) and acetylene via hydrogenolysis and β-elimination, respectively within 12 h by [email protected] Addition of HRJ4 strain into the reaction system effectively enhanced the degradation of the residual TCE, cis-DCE and acetylene to ethylene. Acetylene was the main product in chemical process, whereas ethylene was the main product in biological process as strain HRJ4 could reduce acetylene to ethylene effectively. The results of this study signify the potential application of [email protected]/HRJ4 chem-bio hybrid system for complete degradation of TCE in the anaerobic environment.
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http://dx.doi.org/10.1016/j.watres.2018.09.038DOI Listing
December 2018

Effect of Hemodilution In Vitro with Hydroxyethyl Starch on Hemostasis.

Med Sci Monit 2017 May 8;23:2189-2197. Epub 2017 May 8.

Department of Anesthesiology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China (mainland).

BACKGROUND Hydroxyethyl starch (HES) solutions are used for volume expansion during surgery. We aimed to investigate how 6%HES 130/0.4 affects hemostasis. MATERIAL AND METHODS Blood samples were collected from 12 healthy adult volunteers, diluting with 6%HES 130/0.4 (HES group) or Ringer lactate solution (RL control group). The hemodilution ratio (HR) of citrated blood volume to plasma substitute volume was 10: 0 (undiluted), 10: 2, 10: 4, and 10: 6. Clotting factors activity was measured. Thrombin generation was monitored. Platelet function was analyzed. RESULTS 1) Activity of coagulation factor was decreased with increasing HR compared to undiluted baseline, and the activity of FVIII was significantly decreased in HES vs. RL. 2) Calibrated automated thrombography (CAT) results showed HES extended lag time, time to peak (ttpeak), start tail, and decreased peak of thrombin generation. Although lag time and ttpeak were significantly prolonged in HES vs. RL, endogenous thrombin potential (ETP) did not change. 3) Flow cytometric (FCM) analysis showed that HES reduced platelet phospholipids serine (PS) vs. baseline and RL. 4) HES significantly decreased antithrombin activity (AT: A) of the anticoagulant system with increasing HR vs. baseline and RL. 5) For fibrinolytic system, HES did not affect fibrinogen degradation products (FDP) and D-dimers (D-D) vs. baseline, or α2-antiplasmin (α2-AP) vs. RL. CONCLUSIONS By reducing FVIII activity and platelet PS expression, HES interfered with PS combining to FXIa, FVIIIa, and FVa, which affected the acceleration and explosion stage of thrombin. The decreased velocity and peak of thrombin generation delays and reduces clot formation. Combined 6%HES 130/0.4 decreased anticoagulant activity and may have clinical utility.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5436429PMC
http://dx.doi.org/10.12659/msm.901588DOI Listing
May 2017

Simultaneous removal of NO and Hg over Ce-Cu modified VO/TiO based commercial SCR catalysts.

J Hazard Mater 2017 May 12;330:83-92. Epub 2017 Feb 12.

College of Environmental Science & Engineering, Nankai University, Tianjin 300350, China.

A series of novel Ce-Cu modified VO/TiO based commercial SCR catalysts were prepared via ultrasonic-assisted impregnation method for simultaneous removal of NO and elemental mercury (Hg). Nitrogen adsorption, X-ray diffraction (XRD), temperature programmed reduction of H (H-TPR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts. 7% Ce-1% Cu/SCR catalyst exhibited the highest NO conversion efficiency (>97%) at 200-400°C, as well as the best Hg oxidation activity (>75%) at 150-350°C among all the catalysts. The XPS and H-TPR results indicated that 7% Ce-1% Cu/SCR possess abundant chemisorbed oxygen and good redox ability, which was due to the strong synergy between Ce and Cu in the catalyst. The existence of the redox cycle of Ce+Cu↔Ce+Cu could greatly improve the catalytic activity. 7% Ce-1% Cu/SCR showed higher resistance to SO and HO than other catalysts. NO has a promoting effect on Hg oxidation. The Hg oxidation activity was inhibited by the injection of NH, which was due to the competitive adsorption and oxidized mercury could be reduced by ammonia at temperatures greater than 325°C. Therefore, Hg oxidation could easily occurred at the outlet of SCR catalyst layer due to the consumption of NH.
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http://dx.doi.org/10.1016/j.jhazmat.2017.02.013DOI Listing
May 2017

UiO-66 and its Br-modified derivates for elemental mercury removal.

J Hazard Mater 2016 Dec 16;320:556-563. Epub 2016 Aug 16.

School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, China.

Phenyl bromine-appended metal-organic frameworks (Br-MOFs) were synthesized and applied in elemental mercury (Hg) removal from simulated flue gas, considering the stability of bromine on the materials at the same time. The techniques of PXRD, nitrogen adsorption, TGA and XPS were used to characterize the materials. Phenyl bromide on the MOFs was the main active site for Hg capture. The optimal Br-MOF showed high Hg removal efficiency of more than 99% for 48h at 200°C, whereas the efficiency of un-functionalized MOF and conventional bromine impregnated active carbon dropped to 59.8% and 91.2% within 5h, respectively. The crystalline integrity of the Br-MOF was maintained after Hg adsorption. Br-MOF exhibited enhanced Hg removal efficiency when SO was introduced to the flue gas. However, exposure Br-MOF to flue gas with steam resulted in low Hg removal efficiency. Bromine leaching experiments proved that Br-MOFs have high bromine stability over the Hg adsorption process, avoiding the possible bromine pollution caused by the conventional bromine impregnated adsorbents. All of these results demonstrated the phenyl bromine-appended MOFs to be potential Hg adsorbent regarding its high Hg capture efficiency and low environmental risk.
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http://dx.doi.org/10.1016/j.jhazmat.2016.08.039DOI Listing
December 2016

Start-up performance of Anammox process in a fixed bed reactor (FBR) filled with honeycomb-like polypropylene carriers.

Water Sci Technol 2016 ;73(8):1848-54

Department of Environmental Engineering, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China E-mail:

Novel honeycomb-like carriers, made of polypropylene, were applied to enhance biomass retention capacity so as to improve Anammox start-up performance in a fixed bed reactor (FBR). The reactor was operated for 3 months. On day 45, Anammox activity appeared. After 61 days' operation, the removal efficiencies of ammonium and nitrite were both over 91% based on 70 mg N L(-1) of the influent ammonium and influent nitrite, indicating that a remarkable Anammox activity was attained. A final specific Anammox activity of 0.12 g NH4(+)-N gVSS(-1) d(-1) was reached (VSS: volatile suspended solids). The FBR showed a good capacity for resisting shock loading and was more able to resist shock loading of nitrogen concentration than resist hydraulic shock loading. Phylogenetic analysis showed that Candidatus Brocadia anammoxidans' and Candidatus Kuenenia stuttgartiensis' were detected in the mature biofilm, and Candidatus Brocadia anammoxidans' was the dominant Anammox strain. Candidatus Kuenenia stuttgartiensis' played a positive role in the reactor performance, as it could consumed nitrite quickly and efficiently so as to avoid an adverse effect of temporary nitrite accumulation. The results showed that the honeycomb-like carriers were suitable for start-up of Anammox.
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http://dx.doi.org/10.2166/wst.2016.017DOI Listing
August 2016

Effects of flue gas components on removal of elemental mercury over Ce-MnOx/Ti-PILCs.

J Hazard Mater 2016 Mar 27;304:10-7. Epub 2015 Oct 27.

College of Environmental Science and Engineering, Nankai University, Tianjin, China.

The adsorption and oxidation of elemental mercury (Hg(0)) under various flue gas components were investigated over a series of Ce-MnOx/Ti-PILC catalysts, which were synthesized by an impregnation method. To discuss the mechanism, the catalysts were characterized by various techniques such as N2 adsorption-desorption, scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) analysis and X-ray photoelectron spectroscopy (XPS). The results indicated that the presence of 500 ppm SO2 in the flue gas significantly restrained the Hg(0) adsorption and oxidation over 6%Ce-6%MnOx/Ti-PILC due to the formation of SO4(2-) species. Hg(0) could be oxidized to HgCl2 in the presence of HCl, because the Deacon process occurred. NO would react with active oxygen to form NO2-containing species, which facilitated Hg(0) oxidation. While the presence of NO limited the Hg(0) adsorption on 6%Ce-6%MnOx/Ti-PILC due to the competitive adsorption of NO with Hg(0). The addition of NH3 in the flue gas significantly restrained Hg(0) adsorption and oxidation, because the formed NH4(+) species covered the active adsorption sites on the surfaces, and further limited Hg(0) oxidation. However, when NO and NH3 were simultaneously added into the flue gas, the Hg(0) oxidation efficiency of 6%Ce-6%MnOx/Ti-PILC exhibited a relatively high value (72%) at 250°C, which indicated the practicability to use Ce-MnOx/Ti-PILC for Hg(0) removal under SCR conditions.
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http://dx.doi.org/10.1016/j.jhazmat.2015.10.044DOI Listing
March 2016

Simultaneous Removal of NO and Hg(0) from Flue Gas over Mn-Ce/Ti-PILCs.

Environ Sci Technol 2015 Aug 22;49(15):9355-63. Epub 2015 Jul 22.

†College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.

A series of Mn-Ce/Ti-PILCs (PILCs, pillared interlayered clays) catalysts were prepared via impregnation method in simultaneous removal of NO and elemental mercury in simulated flue gas. The physicochemical properties of these catalysts have been examined by some characterization methods, such as H2-TPR, nitrogen adsorption, XRD and XPS. Mn(6%)-Ce(6%)/Ti-PILCs exhibited superior NO conversion (>95%) and Hg(0) removal efficiency (>90%) at low temperature (250 °C). The results indicated that the elemental mercury had little impact on NO removal efficiency, while the presence of NH3 and NO in SCR system inhibited the Hg(0) removal. NO and Hg(0) removal activity was strongly affected by the transform between surface adsorbed oxygen and lattice oxygen. The species ratio of Mn(4+)/Mn(3+) and Ce(4+)/Ce(3+) on the catalyst surface contributed to the NO conversions and Hg(0) removal. Mn-Ce/Ti-PILCs displayed a broad prospect for controlling the emission of NO and mercury. On the basis of the results obtained, a mechanism for the simultaneous removal of NO and Hg(0) was proposed for the Mn-Ce/Ti-PILCs catalysts: -NH2 + NO → N2 + H2O, -OH + 1/2 Hg(ad) →1/2 HgO + 1/2 H2O.
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http://dx.doi.org/10.1021/acs.est.5b01435DOI Listing
August 2015

Removal of element mercury by medicine residue derived biochars in presence of various gas compositions.

J Hazard Mater 2015 Nov 21;298:162-9. Epub 2015 May 21.

College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.

Pyrolyzed biochars from an industrial medicinal residue waste were modified by microwave activation and NH4Cl impregnation. Mercury adsorption of different modified biochars was investigated in a quartz fixed-bed reactor. The results indicated that both physisorption and chemisorption of Hg(0) occurred on the surface of M6WN5 which was modified both microwave and 5wt.% NH4Cl loading, and exothermic chemisorption process was a dominant route for Hg(0) removal. Microwave activation improved pore properties and NH4Cl impregnation introduced good active sites for biochars. The presence of NO and O2 increased Hg(0) adsorption whereas H2O inhibited Hg(0) adsorption greatly. A converse effect of SO2 was observed on Hg(0) removal, namely, low concentration of SO2 promoted Hg(0) removal obviously whereas high concentration of SO2 suppressed Hg(0) removal. The Hg(0) removal by M6WN5 was mainly due to the reaction of the C−Cl with Hg(0) to form HgCl2, and the active state of C−Cl(*) groups might be an intermediate group in this process. Thermodynamic analysis showed that mercury adsorption by the biochars was exothermic process and apparent adsorption energy was 43.3 kJ/mol in the range of chemisorption. In spite of low specific surface area, M6WN5 proved to be a promising Hg(0) sorbent in flue gas when compared with other sorbents.
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http://dx.doi.org/10.1016/j.jhazmat.2015.05.031DOI Listing
November 2015

A comprehensive assessment of human exposure to phthalates from environmental media and food in Tianjin, China.

J Hazard Mater 2014 Aug 2;279:133-40. Epub 2014 Jul 2.

College of Environmental Science and Engineering, Nankai University, Weijin Road 94, Tianjin 300071, China.

A total of 448 samples including foodstuffs (rice, steamed bun, vegetables, meat, poultry, fish, milk and fruits), ambient PM10, drinking water, soil, indoor PM10 and indoor dust samples from Tianjin were obtained to determine the distribution of six priority phthalates (PAEs) and assess the human exposure to them. The results indicated that DBP and DEHP were the most frequently detected PAEs in these samples. The concentrations of PAEs in environmental media were higher than those in food. We estimated the daily intake (DI) of PAEs via ingestion, inhalation and dermal absorption from five sources (food, water, air, dust and soil). Dietary intake was the main exposure source to DEP, BBP, DEHP and DOP, whereas water ingestion/absorption was the major source of exposure to DBP, DEHP and DOP. Although food and water were the overwhelmingly predominant sources of PAEs intake by Tianjin population, contaminated air was another important source of DMP, DEP and DBP contributing to up to 45% of the exposure. The results of this study will help in understanding the major pathways of human exposure to PAEs. These findings also suggest that human exposure to phthalate esters via the environment should not be overlooked.
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http://dx.doi.org/10.1016/j.jhazmat.2014.06.055DOI Listing
August 2014
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