The Experts below are selected from a list of 16530 Experts worldwide ranked by ideXlab platform
Zhijun Zhang - One of the best experts on this subject based on the ideXlab platform.
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preparation of superhydrophobic oleophilic Quartz Sand filter and its application in oil water separation
Applied Surface Science, 2018Co-Authors: Xiaohong Li, Zhijun Zhang, Laigui YuAbstract:Abstract It is imperative and challenging to develop environmentally acceptable and cost-effective materials which can readily separate stable emulsions like diesel-in-water emulsion stabilized with surfactants. Thus we attempt to prepare superhydrophobic-oleophilic nano-silica powders with an aggregate diameter of about 300 nm and a surface area of 231.2 m2/g by a surface modification method. Quartz Sand surface are treated by as-obtained superhydrophobic-oleophilic silica nanoparticles containing only ca 0.4 wt% of organic functional groups to alter its intrinsic hydrophilicity to superhydrophobicity (with a water contact angle of 154.0 ± 1.2° and a sliding angle of about 4°). The resultant superhydrophobic Quartz Sand exhibits oleophilicity and can act as a high performance filter to separate oil-water mixture with a good reusability, which makes it feasible for the oil film on the surface of water to be fully adsorbed by the treated Quartz Sand and easily separated from the water. In the meantime, the treated Quartz Sand filter can break the stability of surfactant stabilized oil/water emulsion, thereby facilitating the efficient separation of the oil phase from the aqueous phase. The as-prepared superhydrophobic and lipophilic Quartz Sand could be used as a cost-effective and environmentally acceptable filter for oil-water separation in petrochemical industry.
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Improving water-injection performance of Quartz Sand proppant by surface modification with surface-modified nanosilica
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015Co-Authors: Peisong Liu, Sai Guo, Mingming Lian, Zhijun ZhangAbstract:Abstract Nanoscale silica (denoted as nano-SiO 2 ) with a size of 15–20 nm was surface-modified by hexamethyldisiloxane (HMDS) via in situ surface-modification route to achieve strong hydrophobicity. Resultant super-hydrophobic nano-SiO 2 (denoted as HMDS-modified nano-SiO 2 ) was adopted to modify Quartz Sand proppant so as to acquire hydrophobicity and improve the water-injection performance, while the Quartz Sand modified by HMDS alone was also fabricated for a comparative study. The chemical features of the Quartz Sands surface-modified by HMDS and by HMDS-modified nano-SiO 2 were investigated by Fourier transform infrared spectrometry, and their morphology was observed with a field emission scanning electron microscope. The water contact angles of the Quartz Sand proppants before and after surface modification were measured to evaluate the wettability. Moreover, laboratory displacement tests were conducted to estimate the water-injection performance of the Quartz Sand surface-modified by HMDS-modified nano-SiO 2 , with which the surface-modified Quartz Sand proppant was filled into a glass tube and compacted, and then the rate of the water flowing through the compacted Quartz Sand was measured. It was found that, as compared with the Quartz Sand surface-modified by HMDS alone, the one surface-modified by HMDS-modified nano-SiO 2 exhibits significantly increased hydrophobicity, which is attributed to the formation of a dense nano-silica layer on the Quartz Sand surface by way of chemical bonding between the active hydroxyl groups of the HMDS-modified nano-SiO 2 and of the Quartz Sand. More importantly, the Quartz Sand surface-modified by HMDS-modified nano-SiO 2 exhibits greatly improved water-injection performance than the one surface-modified by HMDS, showing great potential for crude oil exploration from water-injection wells.
Laigui Yu - One of the best experts on this subject based on the ideXlab platform.
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preparation of superhydrophobic oleophilic Quartz Sand filter and its application in oil water separation
Applied Surface Science, 2018Co-Authors: Xiaohong Li, Zhijun Zhang, Laigui YuAbstract:Abstract It is imperative and challenging to develop environmentally acceptable and cost-effective materials which can readily separate stable emulsions like diesel-in-water emulsion stabilized with surfactants. Thus we attempt to prepare superhydrophobic-oleophilic nano-silica powders with an aggregate diameter of about 300 nm and a surface area of 231.2 m2/g by a surface modification method. Quartz Sand surface are treated by as-obtained superhydrophobic-oleophilic silica nanoparticles containing only ca 0.4 wt% of organic functional groups to alter its intrinsic hydrophilicity to superhydrophobicity (with a water contact angle of 154.0 ± 1.2° and a sliding angle of about 4°). The resultant superhydrophobic Quartz Sand exhibits oleophilicity and can act as a high performance filter to separate oil-water mixture with a good reusability, which makes it feasible for the oil film on the surface of water to be fully adsorbed by the treated Quartz Sand and easily separated from the water. In the meantime, the treated Quartz Sand filter can break the stability of surfactant stabilized oil/water emulsion, thereby facilitating the efficient separation of the oil phase from the aqueous phase. The as-prepared superhydrophobic and lipophilic Quartz Sand could be used as a cost-effective and environmentally acceptable filter for oil-water separation in petrochemical industry.
Chang Qing - One of the best experts on this subject based on the ideXlab platform.
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Fabrication of superhydrophilic and underwater superoleophobic Quartz Sand filter for oil/water separation
Separation and Purification Technology, 2019Co-Authors: Wei Bigui, Liu Jianlin, Dai Liang, Song Xiaosan, Wu Fuping, Yue Cheng, Li Hua, Wang Gang, Chang QingAbstract:Abstract To improve the oil/water separation efficiency of granular filtration, chitosan and SiO2 nanoparticles have been grafted onto the surface of Quartz Sand to prepare a superhydrophilic and underwater superoleophobic chitosan coated Quartz Sand filter media (CHQS). The separation efficiency of the CHQS for a mixture of engine oil and water has reached 99.99%, and the oil concentration in the separated water is only 1/8 of that from the pristine Quartz Sand filter. The outlet oil concentration of the emulsified oily wastewater is 24.4 percentage points lower than that of the pristine Quartz Sand filter. The water and oil hydraulic conductivities have increased by 19% and decreased by 6%, respectively, compared to the pristine Quartz Sand filter. The filter shows strong stability under harsh environments. The results indicate that the CHQS is feasible for highly efficient oil/water separation.
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Silane coupling agent for surface modification of Quartz Sand filter medium
China Environmental Science, 2013Co-Authors: Bao Caixia, Wei Bigui, Chang QingAbstract:The Quartz Sand was surface modified using silane coupling reagent KH-550 to improve the hydrophobicity of filter medium as well as increase the oily wastewater treatment performance.The effect of the concentration of the silane coupling agent KH-550,modified temperature and stirring time on modification were studied by orthogonal and single-factor approach.Results show that when the KH-550 concentration was 15%,reaction temperature was 110℃ and stirring time was 15min,Quartz Sand modification had the best effect.Wetting weight of water could be reduced from 1.5589g to 0.0607g by surface modification while oil wetting weight were almost unchanged before and after modification.The adsorption capacity of modified Quartz Sand was greatly improved to 0.1843 for oil,and was 27.72% higher than unmodified Quartz Sand.XPS and SEM shown that KH-550 combined in the surface of the Quartz Sand with chemical bonds,form a solid organic coated layer.
Qing Chang - One of the best experts on this subject based on the ideXlab platform.
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Superhydrophobic coating on Quartz Sand filter media for oily wastewater filtration
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2018Co-Authors: Hongwei Zhang, Fuping Wu, Qing ChangAbstract:Abstract Deep bed filtration is commonly used to remove oil from oily wastewater. The wettability of the filter media greatly influences the oil removal efficiency. A filter with a strong hydrophobicity and oleophilicity results in a higher oil removal efficiency. To improve the hydrophobicity and oleophilicity, ZnO nanoparticles and octadecyltrichlorosilane (OTS) were coated on Quartz Sand filter media. SEM, FTIR and XPS were used to study the morphology and chemical composition of the filters, and adsorption capacity and oil removal efficiency experiments were performed to assess the oil removal performance. The results show that the OTS molecules are grafted onto the surface of the Quartz Sand filter through chemical bonding, and the OTS/ZnO-coated Quartz Sand filter is superhydrophobic and oleophilic, with a water contact angle of 154.1° and an oil contact angle of 0°. The OTS/ZnO-coated Quartz Sand filter has very high mechanical stability and acid resistance. The oily wastewater treatment performance is greatly improved after application of the OTS/ZnO coating, and the superhydrophobic Quartz Sand filter media can potentially be used to filter oily wastewater and achieve high oil removal efficiency.
Xiaohong Li - One of the best experts on this subject based on the ideXlab platform.
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preparation of superhydrophobic oleophilic Quartz Sand filter and its application in oil water separation
Applied Surface Science, 2018Co-Authors: Xiaohong Li, Zhijun Zhang, Laigui YuAbstract:Abstract It is imperative and challenging to develop environmentally acceptable and cost-effective materials which can readily separate stable emulsions like diesel-in-water emulsion stabilized with surfactants. Thus we attempt to prepare superhydrophobic-oleophilic nano-silica powders with an aggregate diameter of about 300 nm and a surface area of 231.2 m2/g by a surface modification method. Quartz Sand surface are treated by as-obtained superhydrophobic-oleophilic silica nanoparticles containing only ca 0.4 wt% of organic functional groups to alter its intrinsic hydrophilicity to superhydrophobicity (with a water contact angle of 154.0 ± 1.2° and a sliding angle of about 4°). The resultant superhydrophobic Quartz Sand exhibits oleophilicity and can act as a high performance filter to separate oil-water mixture with a good reusability, which makes it feasible for the oil film on the surface of water to be fully adsorbed by the treated Quartz Sand and easily separated from the water. In the meantime, the treated Quartz Sand filter can break the stability of surfactant stabilized oil/water emulsion, thereby facilitating the efficient separation of the oil phase from the aqueous phase. The as-prepared superhydrophobic and lipophilic Quartz Sand could be used as a cost-effective and environmentally acceptable filter for oil-water separation in petrochemical industry.