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硅藻土的有机改性及其对腐植酸的吸附 总被引:2,自引:0,他引:2
曹亚丽 《青岛科技大学学报(自然科学版)》2006,27(6):486-490
以云南腾冲硅藻土为原料,在对原硅藻土进行提纯后,采用聚二甲基二烯丙基氯化铵(PDMDAAC)作为改性剂,对硅藻精土进行了有机改性,制备成新型的有机改性硅藻土,用于吸附去除水中腐植酸。同时,考察了各种因素(pH值、投加量、吸附时间、温度)对PDMDAAC-硅藻土吸附去除腐植酸的影响。 相似文献
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Jiu‐Hong Li Yi‐Xin Guan Hai‐Qing Wang Shan‐Jing Yao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(2):208-214
BACKGROUND: Arthrobacter simplex cells immobilised in sodium cellulose sulfate/poly‐dimethyl‐diallyl‐ammonium chloride microcapsules were used for the microbial dehydrogenation of 11α‐hydroxy‐16α,17‐epoxyprogesterone to 11α‐hydroxy‐16α,17α‐epoxypregn‐1,4‐diene‐3,20‐dione in an aqueous/organic solvent two‐liquid‐phase system, which is a key reaction in the production of glucocorticoid pharmaceuticals. The aim of the study was to establish a suitable aqueous/organic solvent two‐liquid‐phase system for performing semi‐continuous production in an airlift loop reactor by encapsulated A. simplex cells with the addition of suitable surfactants to achieve a higher yield of the product. RESULTS: n‐Hexane was selected as the most suitable organic solvent. In optimised Tween‐80 emulsion feed mode the conversion in the airlift loop reactor was as high as 97.54% when the time of reaction was 2 h, and the reaction time was greatly shortened. In semi‐continuous production the cultivation with immobilised cells was carried out for five batches in total. The conversion in each batch was above 95% and the enzymatic activity still remained quite high after five batches of biotransformation. CONCLUSION: The results showed that performing the conversion by this method shortened the reaction time and increased the productivity, thus demonstrating the great potential of the method for the dehydrogenation of 11α‐hydroxy‐16α,17‐epoxyprogesterone. Copyright © 2008 Society of Chemical Industry 相似文献
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用一步法合成DMDAAC单体,采用APS—TEA复合引发体系引发聚合得到PDMDAAC。实验取100mL质量分数为72%的DMDAAC溶液,通N2 30min后加入APS 0.548g、TEA0.352g、EDTA·2Na 15.04mg,当反应温度为42℃,反应时间为24h时,DMDAAC的转化率为82.26%,PDMDAAC的特征粘度为1.06dL/g。采用PFS(聚合硫酸铁)、PDMDAAC和PFS—PDMDAAC复合絮凝剂处理Cu^2+、pb^2+浓度均为10mg/L的模拟重金属污水,PFS—PDMDAAC复合絮凝剂处理效果最好。控制模拟污水的终点DH值约为8.5,使用PFS-PDMDAAC复合絮凝剂,当PFS剂量为5.52mg/L、PDMDAAC剂量为0.39mg/L时,处理后Cu^2+、Pb^2+去除率分别达到99.8%和99.9%。 相似文献
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《分离科学与技术》2012,47(12):1828-1836
Cationic hydrogels, poly(dimethyl diallyl ammonium chloride)/polyacrylamide (PDMDAAC/PAM), were prepared for the removal of congo red (CR) from aqueous solution. Process parameters affecting the adsorption efficiency were systematically investigated. The results showed that the calculated monolayer adsorption capacity of the cationic hydrogels was found to be 200 to 465 mg/g. The hydrogels showed appreciable adsorption capacities within pH range investigated. The adsorption process well obeyed pseudo-second-order kinetics and the Langmuir isotherm. The ion exchange dominated the whole adsorption mechanism. All the information suggests that the as-prepared cationic hydrogels show potential applications in the fields of wastewater treatment for the removal of anionic dyes such as CR. 相似文献
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研究了用聚二甲基二烯丙基氯化铵(PDMDAAC)改性凹凸棒石对微污染水中痕量硝基苯的吸附性能、影响因素及其再生后吸附效果。结果表明:PDMDAAC改性凹凸棒石对微污染水中痕量苯酚具有较强的吸附能力,在PH=8、硝基苯浓度为50μg/L、投加量为5g/L、吸附时间30min的条件下,吸附去除率达73%;改性后的凹凸棒石可用碱进行再生,再生后对硝基苯的吸附能力没有明显下降;改性凹凸棒石的等温静态吸附曲线呈线性关系。 相似文献
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谢刚 《西华大学学报(自然科学版)》2009,28(1)
研究了用聚二甲基二烯丙基氯化铵(PDMDAAC)改性凹凸棒石对微污染水中痕量硝基苯的吸附性能、影响因素及其再生后吸附效果.结果表明:PDMDAAC改性凹凸棒石对微污染水中痕量苯酚具有较强的吸附能力,在pH=8、硝基苯浓度为50ug/L、投加量为5g/L、吸附时间30min的条件下,吸附去除率达73%;改性后的凹凸棒石可用碱进行再生,再生后对硝基苯的吸附能力没有明显下降;改性凹凸棒石的等温静态吸附曲线呈线性关系. 相似文献
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PDMDAAC改性粉煤灰的制备及其脱色效果研究 总被引:8,自引:0,他引:8
为提高粉煤灰的除污能力,采用高分子絮凝剂PDMDAAC(聚二甲基二烯丙基氯化铵)对粉煤灰进行表面改性,并通过正交试验考察了改性的最佳工艺参数。结果表明,改性的最佳工艺参数为:PDMDAAC的浓度为40g/L,温度恒定为30℃,反应时间为1h。改性粉煤灰对活性黄和分散红紫的模拟染料废水都有很好的处理效果,其脱色机理以吸附电中和为主。在一定范围内,随着改性粉煤灰投量的增加则脱色效果增强,而溶液的pH值和反应时间对脱色效果的影响不大。此改性粉煤灰可用于印染废水的处理。 相似文献