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排序方式: 共有2127条查询结果,搜索用时 15 毫秒
81.
本文选择食堂废弃的地沟油为研究对象,通过控制水解条件,获得不同性质的地沟油改性捕收剂。分别探究温度、催化剂、乳化剂用量等因素对地沟油水解的影响规律,确定其最佳的改性条件。采用接触角测定表征地沟油的改性效果,通过比较地沟油改性捕收剂在固废浮选方面的应用效果。结果表明地沟油改性剂具有一定的捕收作用,在浮选分离领域,可替代传统脂肪酸类捕收剂及非极性烃类捕收剂的使用。 相似文献
82.
氯乙烯生产过程中"三废"的处理 总被引:1,自引:0,他引:1
介绍了氯乙烯生产过程中触媒废气、氯乙烯废水、酸性废水、碱性废水、精馏尾气及高沸物的处理方法.经过处理,减少了废水和废气的排放量,回收了氯乙烯,既达到了清洁生产的目的又降低了物料消耗. 相似文献
83.
Kyeong-Ho Yeon Heesu Park Seung-Hak Lee Yong-Min Park Sang-Hyup Lee Masakazu Iwamoto 《Korean Journal of Chemical Engineering》2008,25(5):1040-1046
Eutrophication caused by the excessive supply of phosphate to water bodies has been considered as one of the most important
environmental problems. In this study, the powder of zirconium mesostructure (ZM), which was prepared with the template of
surfactant, was immobilized in calcium alginate for practical application and the resulting material was tested to evaluate
the phosphate removal efficiency. Sorption isotherms and kinetic parameters were obtained by using the entrapped ZM beads
with 30 to 60% of ZM. The maximum sorption capacity increased with the higher ZM content. Q
max
in Langmuir isotherm was 51.74 mg/g for 60% of ZM with 7 mm of size. The smaller the particle size of the ZM beads, the faster
the rate of phosphate removal, because the phosphate ions had less distance to reach the internal pores of the immobilized
ZM beads. Chemical and electrochemical regeneration techniques were compared. Phosphates adsorbed on the ZM beads were effectively
desorbed with NaCl, NaOH, and Na2SO4 solutions. An electrochemical regeneration system consisting of an anion exchange membrane between two platinum-coated titanium
electrodes was successfully used to desorb and regenerate the phosphate-saturated ZM beads. Complete regeneration was reached
under optimal experimental conditions. Chemical and electrochemical regeneration proved the reusability of the bead form of
the entrapped ZM, and will enhance the economical performance of the phosphate treatment process. 相似文献
84.
85.
Jianrong Ma Zhenyu Liu Shoujun Liu Zhenping Zhu 《Applied catalysis. B, Environmental》2003,45(4):301-309
A novel regenerable Fe/activated coke (AC) desulfurizer prepared by impregnation of Fe(NO3)3 on an activated coke was investigated. Experiment results showed that at 200 °C the SO2 adsorption capacity of the Fe/AC was higher than that of AC or Fe2O3. Temperature-programmed desorption (TPD) revealed that H2SO4 and Fe2(SO4)3 were generated on the desulfurizer upon adsorption of SO2. Effect of desulfurization temperature was also investigated which revealed that with increasing temperature from 150 to 250 °C, the SO2 removal ability gradually increases. The used Fe/AC can be regenerated by NH3 at 350 °C to directly form solid ammonium-sulfate salts. 相似文献
86.
87.
M. Hasib-ur-Rahman M. Siaj F. Larachi 《Chemical Engineering and Processing: Process Intensification》2010
Innovative off-the-shelf CO2 capture approaches are burgeoning in the literature, among which, ionic liquids seem to have been omitted in the recent Intergovernmental Panel on Climate Change (IPCC) survey. Ionic liquids (ILs), because of their tunable properties, wide liquid range, reasonable thermal stability, and negligible vapor pressure, are emerging as promising candidates rivaling with conventional amine scrubbing. Due to substantial solubility, room-temperature ionic liquids (RTILs) are quite useful for CO2 separation from flue gases. Their absorption capacity can be greatly enhanced by functionalization with an amine moiety but with concurrent increase in viscosity making process handling difficult. However this downside can be overcome by making use of supported ionic-liquid membranes (SILMs), especially where high pressures and temperatures are involved. Moreover, due to negligible loss of ionic liquids during recycling, these technologies will also decrease the CO2 capture cost to a reasonable extent when employed on industrial scale. There is also need to look deeply into the noxious behavior of these unique species. Nevertheless, the flexibility in synthetic structure of ionic liquids may make them opportunistic in CO2 capture scenarios. 相似文献
88.
M. Misk G. Joly P. Magnoux M. Guisnet S. Jullian 《Microporous and mesoporous materials》2000,40(1-3):197-204
Coke formation from propene was investigated at 623 K and Ppropene=100 kPa on a pure 5A zeolite and an industrial adsorbent (5A zeolite 80 wt.%–binder 20 wt.%). The composition and location of coke molecules were determined as a function of time on stream. Coking on the pure zeolite was faster than on the industrial adsorbent. This result is mainly due to the trapping of coke precursors by the binder, and consequently a significant decrease in the amount of coke on the zeolite present in the adsorbent. While the coke deposited on the binder is very polyaromatic, the carbonaceous compounds formed on the zeolite and on the adsorbent are constituted at low coke content by mono-, bi-, tri- and tetra-alkyl aromatic components, and these compounds are sterically blocked in the -cages of the 5A zeolite. At high coke content, very heavy polyaromatic compounds appear and are certainly located on the external surface of the zeolite crystallites. Adsorption measurements of both samples show that coke is heterogeneously distributed in the zeolite pores. Whatever be the adsorbent, the partial oxidation of coke on highly coked samples caused an increase in the adsorption capacity. The first few steps of regeneration of coked samples remove the heavy polyaromatic molecules responsible for the pore blockage and thus liberate the pores which are not occupied by coke molecules. 相似文献
89.
90.