共查询到17条相似文献,搜索用时 140 毫秒
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《化学推进剂与高分子材料》2017,(3):42-45
简要介绍了电子工业用高纯过氧化氢水溶液的应用、现状和杂质来源。综述了通过吸附、离子交换、膜分离、精馏、萃取和结晶等单一单元操作纯化制备高纯过氧化氢水溶液技术,并进行优劣势比较。指出当前高纯过氧化氢水溶液制备技术的发展趋势是单元操作集成,重点介绍了使用较为广泛的"吸附–离子交换–膜分离单元操作集成技术"制备高纯过氧化氢水溶液的工艺。 相似文献
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茶叶活性成分综合提取过程研究 总被引:13,自引:0,他引:13
以低档绿茶为原料,研究了茶多酚、咖啡碱和茶多糖的提取、分离、纯化等工艺条件,探索出一条综合提取新工艺。研究表明,以纤维素酶和果胶酶为主体的复合酶解提取,可提高茶叶中各有效成分的提取率,并可降低其活性损失;通过超滤膜过滤酶提液不但精制了料液而且利用膜浓缩液可方便地制备茶多糖;采用H-600树脂吸附阶段洗脱层析法分离茶多酚咖啡碱,解决了传统工艺中使用有毒溶剂脱除咖啡碱的难题。文章计算了吸附柱的传质区高度和总传质系数,为放大设计奠定了基础。 相似文献
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Qian Lin Yanbin Jiang Jianming Geng Yu Qian 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2008,139(2):264-271
The aim of this research was to select suitable activated carbon (AC) for effective removal of organic impurities from industrial aqueous hydrogen peroxide solution to produce ultra-pure hydrogen peroxide. The textural parameters and surface chemistry of four kinds of AC samples were measured and analyzed. Static and dynamic equilibrium adsorption experiments were carried out to compare the effect of AC on organic impurities adsorption and hydrogen peroxide decomposition. The effects of AC pore structure and surface chemistry on the adsorption of organic impurities were investigated. The fitting operation conditions, i.e., operating temperature and AC dosage, were also examined. The results showed that AC adsorption capacity on organic impurities from industrial aqueous hydrogen peroxide solution was mainly influenced by micropore structure of AC, as well as decomposition of hydrogen peroxide. The pore size of 1–3 nm is most effective for adsorption of organic impurities. It was found that the organic impurities in industrial hydrogen peroxide solution could be reduced effectively to meet the standard of ultra-pure hydrogen peroxide of SEMI-C8 level with the proposed AC and adsorption techniques. 相似文献
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通过被H2O2溶液浸泡前后不同树脂的红外谱图对比,确定了具有抗氧化能力的大孔阴、阳离子交换树脂D072、D 296为净化过氧化氢用树脂。通过D 072、D 296离子交换树脂对H2O2的吸附及脱附行为,H2O2溶液与水溶液中的离子交换平衡的对比研究,从理论上找出了H2O2分解的原因是阴离子交换树脂稳定性稍差,对H2O2的吸附量较大,一旦树脂脱离H2O2溶液,H2O2的浓度骤然增高,与树脂的化学反应加剧,不良的传热条件造成热量的累积,温度迅速上升,形成快速连锁反应,使树脂中过氧化氢瞬时分解,导致树脂的活性基团甚至惰性骨架被破坏和生产过程的不安全性。H2O2一旦中断,应立即采取措施清洗树脂。 相似文献
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生物碱提取与纯化技术应用进展 总被引:11,自引:0,他引:11
生物碱是许多中药的有效成分,提取与纯化是生物碱制备的关键环节。目前较为常用的提取方法有煎煮、浸渍、回流和渗漉;纯化方法有有机溶剂萃取、色谱和树脂吸附。超声、微波辅助提取、超临界流体萃取、分子印迹和膜分离等技术的应用使生物碱制备向高效节能方向发展。本文综述了生物碱制备常用的提取与纯化工艺与新技术的应用进展,分析了它们的原理及优缺点并探讨了发展前景。 相似文献