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991.
本文研究了聚砜,酞侧基聚砜,磺化聚砜,聚丙烯腈,醋酸纤维素,氰乙基醋酸纤维素,氯甲基化聚砜和季胺化聚砜等材质超滤膜的亲水性能,荷电性能以及它们对超滤阳极和阴极电泳漆液的影响,实验结果表明:亲水性较强,电负性较强的氰乙基醋酸纤维素和醋酸纤维素膜,适合用于处理阳极电泳漆液;而亲水性较强,电中性和电正性较强的氯甲基化聚砜和季胺化聚砜膜,则适合用于处理阴极电泳漆液。 相似文献
992.
废水处理一体化生物反应器的发展 总被引:3,自引:0,他引:3
废水处理的一体化生物反应器由于具有投资少、占地小、管理运行方便等特点备受青睐.较早的有一体化氧化沟、SBR反应器、一体式膜生物反应器等.随着一体化反应器的发展,生物膜法被结合起来作为主体工艺,另外好氧工艺也与厌氧/缺氧工艺结合起来,出现了很多系统有机负荷更高、抗冲击能力更强、脱氮除磷效果更好的新式一体化反应器,如AmOn一体化生物反应器、五箱一体化反应池、一体化生物转筒反应器IBDR、A/O一体式曝气生物滤池等.一体化生物反应器的发展适应我国国情,具有广阔的应用和发展前景.参37 相似文献
993.
In this study, sulfuric acid and potassium hydroxide are used as the electrolytes, separated by proton exchange membrane, to produce hydrogen. The effects of electrolyte concentrations, applied voltage, single or dual cells, and temperature on the hydrogen production rate and energy efficiency are investigated. Experimental results show that the amount of hydrogen production increases with voltage, and the dual electrolytes and cells can yield the best hydrogen production rate and energy efficiency. With 1-M KOH plus 1-M H2SO4 as electrolytes in separated cells, the highest hydrogen production rate is about 0.95 L/hr. Results also show that the rise of electrolyte temperature can significantly increase the hydrogen production rate up to 50%, and the energy efficiency up to 20%. Keeping a low PH value in cathodeand high anode PH value in anode indeed enhances the efficiency of hydrogen production rate. 相似文献
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To develop a depth filter based on the electrostatic adsorption principle, positively charged microporous ceramic membrane was prepared from a diatomaceous earth ceramic membrane.The internal surface of the highly porous ceramic membrane was coated with uniformly distributed electropositive nano-Y_2O_3 coating. The dye removal performance was evaluated through pressurized filtration tests using Titan Yellow aqueous solution. It showed that positively charged microporous ceramic membrane exhibited a flow rate of 421 L/(m~2·hr) under the trans-membrane pressure of 0.03 bar. Moreover it could effectively remove Titan Yellow with feed concentration of 10 mg/L between pH 3 to 8. The removal rate increased with the enhancement of the surface charge properties with a maximum rejection of 99.6%. This study provides a new and feasible method of removing organic dyes in wastewater. It is convinced that there will be a broad market for the application of charged ceramic membrane in the field of dye removal or recovery from industry wastewater. 相似文献
997.
S. Shiva Kumar S.U.B. Ramakrishna B. Rama Devi 《International Journal of Green Energy》2018,15(10):558-567
PEM water electrolysis is one of the most efficient methods for the production of hydrogen because of produced high purity of the gases and environmentally friendly. In the present study, Phosphorus-doped Graphene (PG) was synthesized by thermal annealing of triphenylphosphine (TPP) and graphene oxide (GO). The PG supported palladium (Pd/PG) electrocatalysts were synthesized by chemical reduction method and used as the cathode for hydrogen evolution reaction (HER) electrode. Structural properties and electrochemical performances of the synthesized Pd/PG electrocatalyst were studied by FE-SEM, EDS, ICP, FT-IR, XRD, and Cyclic voltammetry (CV) methods, respectively. The membrane electrode assemblies (MEA’s) were fabricated using Pd/PG as cathode for HER electrode and RuO2 as anode for OER electrode. Also, their electrochemical performances along with the corresponding hydrogen yields were evaluated in single cell PEM water electrolyzer at various experimental conditions such as different current densities from 0.1 to 2.0 A cm?2 and temperatures (28–80°C). The synthesized Pd/PG electrocatalyst was observed a current density of 1 A cm?2 with 1.95 V at 80°C. Further, long-term stability studies were carried out continuously up to 2000 h which showed a reasonable stability. Hence, the synthesized Pd/PG can be used as an alternative to Pt-based electrocatalysts for the HER in PEM water electrolysis. 相似文献
998.
Tatiana V. Komarova Michael E. Bartkow Steve Carter 《Environmental pollution (Barking, Essex : 1987)》2009,157(3):731-736
Semipermeable membrane devices (SPMDs) were deployed in water using four different methods: a typical SPMD cage with and without a mesh cover, a bowl chamber and without any protection. In addition to routinely used performance reference compounds (PRCs), perdeuterated dibenz[a,h]anthracene was added. Due to its high sampler to water partition coefficient no measurable clearance due to diffusion was expected during the deployment period, hence any observed loss could be attributed to photodegradation. The loss of PRCs was measured and SPMD-based water concentrations determined. Results showed that a typical SPMD deployment cage covered with mesh provided the best protection from photodegradation. Samplers which had undergone the highest photodegradation underestimated PAH water concentrations by up to a factor of 5 compared to the most protected SPMDs. This study demonstrates that the potential for photodegradation needs to be addressed when samplers are deployed in water of low turbidity. 相似文献
999.
反渗透与超滤及其在水处理中的应用 总被引:6,自引:0,他引:6
反渗透与超滤是水处理中广泛应用的膜分离技术,给水处理中反渗透应用较多,废水处理中超滤应用较广泛。 相似文献
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