Publications by authors named "Zeheng Peng"

2 Publications

  • Page 1 of 1

Atomic Force Microscopy Study of Non-DLVO Interactions between Drops and Bubbles.

Langmuir 2021 Jun 27;37(22):6830-6837. Epub 2021 May 27.

Beijing Key Laboratory of Urban Oil and Gas Distribution Technology, State Key Laboratory of Natural Gas Hydrates, MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing, No. 18 Fuxue Road, Changping District, 102249 Beijing, P. R. China.

The heterointeraction between liquid drops and air bubbles dispersed in another immiscible liquid is studied with the application of the atomic force microscopy (AFM) probe techniques. The tetradecane drops and air bubbles readily coalescence to form a lens-like structure in 100 mM sodium chloride aqueous solution, demonstrating strong hydrophobic (HB) attraction. The interaction range and strength of this hydrophobic attraction between oil drops and air bubbles is investigated by fine control of electrical double layer thicknesses related to specific electrolyte concentrations, and a midrange term in combination with a short-range term is found to present a proper characterization of this hydrophobic attraction. A further step is taken by introducing a triblock copolymer (Pluronic F68) into the aqueous solution, with results indicating that a relatively long-range steric hindrance (SH) furnished by a polymer "brush" surmounts the hydrophobic attraction. Finally, the interaction between a water drop and an air bubble in tetradecane is also measured as a comparison. The repelling action between a hydrophobic body (air bubble) and water drop indicates a strong repulsion. The present results show an interesting understanding of hydrophobic interactions between drops and bubbles, which is of potential application in controlling dispersion stability.
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http://dx.doi.org/10.1021/acs.langmuir.1c00937DOI Listing
June 2021

Magnetic Organic-Inorganic Nanohybrid for Efficient Modification of Paraffin Hydrocarbon Crystallization in Model Oil.

Langmuir 2020 01 7;36(2):591-599. Epub 2020 Jan 7.

Beijing Key Laboratory of Urban Oil and Gas Distribution Technology, MOE Key Laboratory of Petroleum Engineering, National Engineering Laboratory for Pipeline Safety , China University of Petroleum , Beijing 102249 , P. R. China.

Crystallization modification has been applied in many fields, such as materials science, petroleum engineering, and chemical engineering. The modification of organic-inorganic hybrids via paraffin hydrocarbon crystallization has been significantly important for the exploration of undersea oil and gas resources. In this work, a metal oxide organic-inorganic hybrid pour point depressant (MOIH-PPD) is provided along with an analysis of the microscopic structure of the paraffin hydrocarbon crystal employing small-angle X-ray scattering and X-ray diffraction. The MOIH-PPD modified crystal grain exhibited a decrease in the long period and in the radius of gyration of the crystal grain and an increase in the thickness of the interface layer compared with those of the unmodified paraffin crystal. In addition, the synergistic effect of heterogeneous nucleation and the magnetic response of MOIH-PPD on the paraffin hydrocarbon system was also investigated, revealing that the synergism modification yields stress superior to that of MOIH-PPD or magnetic field alone, which provides insight into the possibility of the modification of paraffin hydrocarbon crystallization.
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http://dx.doi.org/10.1021/acs.langmuir.9b03278DOI Listing
January 2020