Publications by authors named "Jiaao Chen"

6 Publications

  • Page 1 of 1

Sustainable and efficient stabilization/solidification of Pb, Cr, and Cd in lead-zinc tailings by using highly reactive pozzolanic solid waste.

J Environ Manage 2022 Jan 11;306:114473. Epub 2022 Jan 11.

School of Resource and Environment Science, Wuhan University, Wuhan, 430072, PR China; Hubei Environmental Remediation Material Engineering Technology Research Center, Wuhan, 430072, PR China. Electronic address:

Lead-zinc tailings (LZTs) are industrial by-products containing a large number of heavy metals that seriously harm the ecological environment and human health. This study was performed to propose a sustainable and efficient method for immobilizing Pb, Cr, and Cd in LZTs by using solid waste. To better assess the immobilization performance and mechanism, the leaching toxicity, fraction distribution, unconfined compressive strength, environmental risk assessment, and hydration products were explored. The LZTs were mixed and molded with different constituents of ground granulated blast furnace slag (GGBFS) and rice husk ashes (RHAs) at different curing temperatures. Results suggest that ≥99% of the Pb, Cr, and Cd were immobilized mainly in the form of residual fractions in the LZTs. The amounts of Pb, Cr, and Cd in the bioavailable fractions notably decreased by approximately 99.83%, 99.58%, and 97.05%, respectively. After stabilization/solidification (S/S) disposal, Pb, Cr, and Cd showed low to even no risk. The RHAs were effective to stabilize Pb, and GGBFS was effective to stabilize Cr. However, both materials showed almost equal effects to Cd. Ettringite, C-S-H gel, and portlandite were the main hydration products to immobilize Pb, Cr, and Cd, and these hydration products provided a source of strength. Honey-comb or reticular network C-S-H gel possessed higher specific surface area, higher pore volume, and bigger pore size than the other materials. The proposed method could explain the sustainability and efficiency of the S/S of Pb, Cr, and Cd in LZTs by using RHAs. This study opens up new perspectives for disposing heavy metal by using accessible agricultural solid waste (i.e., RHAs) in rural areas, and the solidified block shows certain economic benefits.
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http://dx.doi.org/10.1016/j.jenvman.2022.114473DOI Listing
January 2022

Passivation of multiple heavy metals in lead-zinc tailings facilitated by straw biochar-loaded N-doped carbon aerogel nanoparticles: Mechanisms and microbial community evolution.

Sci Total Environ 2022 Jan 3;803:149866. Epub 2021 Sep 3.

School of Resource and Environmental Science, Wuhan University, Wuhan 430072, Hubei, China; Zhaoqing (Wuhan University) Environmental Technology Research Institute, Zhaoqing 526200, Guangdong, China. Electronic address:

Heavy metal (HM) soil pollution has become an increasingly serious problem with the development of industries. Application of biochar in HMs remediation from contaminated environment has attracted considerable research attention during the past decade. Although the mechanism of HMs passivation with biochar has been investigated, effects and mechanisms of interaction among soil-indigenous microbes and novel carbon matrix composites for HMs adsorption and passivation are still unclear. Four different biochar-loaded aerogels, namely, BNCA-1-600, BNCA-1-900, BNCA-2-600, and BNCA-2-900, were synthesized in this study. Adsorption capacity of four kinds of synthetic materials and two types of contrast biochars (BC600 and BC900) to HMs in aqueous solution, passivation capacity of HMs in soil, and effects on soil organic matter and microbial community were explored. Results showed that BNCA-2-900 exhibits excellent adsorption property and a maximum removal capacity of 205.07 mg·g at 25 °C for Pb(II), 105.56 mg·g for Cd(II), and 137.89 mg·g for Zn(II). Leaching concentration of HMs in contaminated soil can meet the national standard of China (GB/T 5085.3-2007) within 120 days. Results of this study confirmed that the additive BNCA-2-900 and coexistence of indigenous microorganisms can effectively reduce bioavailability of HMs. Another potential mechanism may be to remove the passivation of HMs by porous structure and surface functional groups as well as improve the content of organic matter and microbial abundance. The research results may provide a novel perceptive for the development of functional materials and strategies for eco-friendly and sustainable multiple HMs remediation in contaminated soil and water by using a combination of carbon matrix composites and soil-indigenous microorganisms.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149866DOI Listing
January 2022

Microscopic mechanism about the selective adsorption of Cr(VI) from salt solution on nitrogen-doped carbon aerogel microsphere pyrolysis products.

Sci Total Environ 2021 Dec 28;798:149331. Epub 2021 Jul 28.

School of Resource and Environmental Science, Wuhan University, Wuhan 430072, Hubei, China; Zhaoqing (Wuhan University) Environmental Technology Research Institute, Zhaoqing 526200, Guangdong, China. Electronic address:

A series of nitrogen-doped carbon aerogels (NCAs) were obtained through phase reaction polymerization and different carbonization temperatures to enhance adsorption efficacy of hexavalent chromium (Cr[VI]) from wastewater significantly. Factors that influence adsorption properties of carbon aerogel microspheres toward Cr(VI), such as pH, adsorbent content, initial Cr(VI) concentrations, and coexisting anion, were investigated. Three isotherm (Langmuir, Freundlich, and Sips) and three kinetic (pseudofirst-order, pseudosecond-order, and Elovich) models were used to interpret the adsorption process. The adsorption capacity of Cr(VI) reached 180.62 mg·g, which was superior to that of most aerogel adsorbents. In addition to the adsorption effect, the XPS results also showed that N-containing groups on the NCA surface reduce the adsorbed Cr(VI) to the less toxic Cr(III). The prepared sorbent demonstrates a negligible loss in adsorption capacity after 6 cycles. NCAs show acceptable application prospects in selective removal of Cr(VI) ions.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149331DOI Listing
December 2021

Enhanced sludge dewaterability by Fe-rich biochar activating hydrogen peroxide: Co-hydrothermal red mud and reed straw.

J Environ Manage 2021 Oct 9;296:113239. Epub 2021 Jul 9.

School of Resource and Environmental Science, Wuhan University, Wuhan, 430072, Hubei, China; College of Resources and Environment, Anqing Normal University, Anqing, 246011, Anhui, China. Electronic address:

This study proposed Fe-rich biochar (RMRS-BC) produced by the co-hydrothermal treatment of red mud and reed straw, industrial waste and agricultural waste, as a novel sludge conditioner. It had been proven that heterogeneous and homogeneous Fenton reactions occurred during the sludge conditioning process, in which RMRS-BC activated HO to improve sludge dewaterability. Results demonstrated that the optimal condition was 7.5 wt% dry solids (DS) of RMRS-BC at a mass ratio of 1:1 combined with HO. The corresponding water content of sludge cakes and the capillary suction time reduction efficiency were 57.88 wt% and 69.76%, respectively. The FeO supported in the RMRS-BC structure was used as a catalyst to produce heterogeneous reaction, and the Fe leached from the RMRS-BC after acidification happened homogeneous reaction. Double Fenton reaction in sludge conditioning enhanced the production efficiency of ·OH, the sludge flocs were dispersed into smaller particles, more bound water from the extracellular polymeric substances (EPS) was released, and sludge dewaterability performance was improved. Another main mechanism for enhancing dewaterability was to use RMRS-BC as a skeleton builder to reduce the compressibility of sludge cakes and facilitated free water to flow out. In summary, the Fenton oxidation method activated by RMRS-BC is feasible in improving sludge dewatering.
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http://dx.doi.org/10.1016/j.jenvman.2021.113239DOI Listing
October 2021

High-efficiency degradation of phthalic acid esters (PAEs) by Pseudarthrobacter defluvii E5: Performance, degradative pathway, and key genes.

Sci Total Environ 2021 Nov 25;794:148719. Epub 2021 Jun 25.

School of Resource and Environmental Science, Wuhan University, Wuhan 430079, Hubei, China; Zhaoqing (Wuhan University) Environmental Technology Research Institute, Zhaoqing 526200, Guangdong, China. Electronic address:

Phthalic acid esters (PAEs) are a class of biologically accumulated carcinogenic and teratogenic toxic chemicals that exist widely in the environment. This study, Pseudarthrobacter defluvii E5 was isolated from agricultural soils and showed efficient PAEs-degradation and -mineralization abilities for five PAEs, and encouraging PAEs tolerance and bioavailable range for dibutyl phthalate (DBP) and bis(2-ethylhexyl) phthalate (DEHP) (0.25-1200 mg/L). The complete catalytic system in E5 genome enables PAEs to be degraded into monoester, phthalate (PA) and Protocatechuic acid (PCA), which eventually enter the tricarboxylic acid cycle (TCA cycle). The preferred PAEs-metabolic pathway in soil by E5 is the metabolism induced by enzymes encoded by pehA, mehpH, pht Operon and pca Operon. For the first time, two para-homologous pht gene clusters were found to coexist on the plasmid and contribute to PAEs degradation. Further study showed that P. defluvii E5 has a broad application prospect in microplastics-contaminated environments.
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http://dx.doi.org/10.1016/j.scitotenv.2021.148719DOI Listing
November 2021

What medical waste management system may cope With COVID-19 pandemic: Lessons from Wuhan.

Resour Conserv Recycl 2021 Jul 31;170:105600. Epub 2021 Mar 31.

State Environmental Protection Key Laboratory of Soil Health and Green Remediation, 430070 Hubei, Wuhan, China.

The global pandemic caused by the 2019 coronavirus (COVID-19) has led to a dramatic increase in medical waste worldwide. This tremendous increase in medical waste is an important transmission medium for the virus and thus poses new and serious challenges to urban medical waste management. This study investigates the response of medical waste management to the COVID-19 pandemic and subsequent changes in Wuhan City based on the most detailed data available, including waste generation, storage, transportation, and disposal. The results show that despite a 5-fold increase in the demand for daily medical waste disposal in the peak period, the quick responses in the storage, transportation, and disposal sectors during the pandemic ensured that all medical waste was disposed of within 24 hours of generation. Furthermore, this paper discusses medical waste management during future emergencies in Wuhan. The ability of the medical waste management system in Wuhan to successfully cope with the rapid increase in medical waste caused by major public health emergencies has important implications for other cities suffering from the pandemic and demonstrates the need to establish resilient medical emergency systems in urban areas.
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http://dx.doi.org/10.1016/j.resconrec.2021.105600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8011665PMC
July 2021
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