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Ailton C. Lemes Juliana Ribeiro Machado Marcela Lazzare Brites Marco Di Luccio Susana Juliano Kalil 《化学工程与技术》2014,37(10):1805-1812
The operational conditions for an aqueous two‐phase system (ATPS) for β‐galactosidase purification were optimized and applied to the design of a purification strategy as an alternative to the primary purification steps. The ATPS proved to be suitable for the recovery and primary enzyme purification. The purification process design developed by ATPS, diafiltration, ion exchange, and diafiltration/ultrafiltration was successful, yielding a more than tenfold purification. The purification strategy design resulted in a powerful integrated purification and recovery process, an evidence of the potential for a scale‐up of the β‐galactosidase purification process. 相似文献
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与只考虑直接回用的氢网络相比,具有提纯单元的氢网络能显著减少新鲜氢气的消耗量,但其设计及求解提纯目标值过程均更为复杂。对于单杂质、提纯单元采用固定浓度模型的提纯回用氢网络,结合此类网络的特点,提出了一种简捷法确定网络目标值。首先假设提纯后氢物流量足够大,由此得出初始提纯夹点。当初始夹点估算正确时,由夹点之下的需求物流和源物流的流量与杂质质量衡算即可得出提纯回用氢网络的目标值;当初始夹点估算不正确时,可以第一次计算结果为基础判断得出正确夹点,再增加一步简单计算,也可得到提纯回用目标值。计算实例表明本文方法计算简单且有效。 相似文献
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天然气汽车尾气引起的环境问题日益严重,传统的三效催化剂上甲烷转化率低,净化效果差,天然气汽车尾气净化催化剂受到广泛关注。概述天然气汽车尾气净化催化剂组成以及理论空燃比和稀燃比催化净化原理,介绍四类天然气汽车尾气净化催化剂研究现状,并对未来天然气汽车尾气净化催化剂发展进行展望。 相似文献
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Deep Purification of Zinc Ammoniacal Leaching Solution 总被引:1,自引:0,他引:1
Deep purification of zinc ammoniacal leaching solution by cementation using zinc dust was studied. The effects of relative amount of metallic impurities, dosage of zinc dust, purification time, temperature, pH value and total ammonia concentration in the solution on the purification of the solution were investigated. The results indicate that total ammonia concentration in the solution had no effect on the purification, but relative amount of metallic impurities, dosage of zinc dust, purification time, temperature and pH value of the solution were the main factors influencing the purification. Keeping appropriate molar ratio of copper to cadmium or nickel to cadmium was beneficial to the cementation of cadmium. Nevertheless, the presence of cobalt went against the cementation of cadmium and cobalt. All metallic impurities could be decreased to acceptable levels under the optimized conditions of 2 g/L of zinc dust dosage, 1 h of purification time, 35℃, pH value 9.03 of zinc ammoniacal leaching solution. The deeply purified zinc ammoniacal solution obtained by one-stage purification meets the requirements of zinc electrowinning. 相似文献
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Deep purification of zinc ammoniacal leaching solution by cementation using zinc dust was studied.The effects of relative amount of metallic impurities,dosage of zinc dust,purification time,temperature,pH value and total ammonia concentration in the solution on the purification of the solution were investigated.The results indicate that total ammonia concentration in the solution had no effect on the purification,but relative amount of metallic impurities,dosage of zinc dust,purification time,temperature and pH value of the solution were the main factors influencing the purification.Keeping appropriate molar ratio of copper to cadmium or nickel to cadmium was beneficial to the cementation of cadmium.Nevertheless,the presence of cobalt went against the cementation of cadmium and cobalt.All metallic impurities could be decreased to acceptable levels under the optimized conditions of 2 g/L of zinc dust dosage,1 h of purification time,35℃,pH value 9.03 of zinc ammoniacal leaching solution.The deeply purified zinc ammoniacal solution obtained by one-stage purification meets the requirements of zinc electrowinning. 相似文献
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介绍了电石炉气的基本性质、几种主要炉气净化和利用方法,干法净化技术以及挪威埃肯公司干法(布袋式)净化工艺在国内的应用和发展,最后提出了优化炉气净化技术方案和实施方法的建议。 相似文献
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综述了农用氯化铵精制的研究进展和方法。对含氯化钾的农用氯化胺进行了精制研究,确定了对含氯化钾的农用氯化铵精制工艺的实验方法,确定了添加剂,提出了精制的最佳工艺条件,其产品质量达到了工业一级的国家标准。 相似文献
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基于氢网络的集成以及AB5型储氢材料LaNi4.75Fe0.25及LaNi4.85Al0.15的特性,对储氢提纯在氢网络中的应用进行研究。综合考虑LaNi4.75Fe0.25及LaNi4.85Al0.15储氢/放氢动力学,建立了储氢提纯氢网络的优化方法,根据单位质量储氢材料提纯的节氢能力和公用工程节省量与提纯参数的关系,确定最优提纯氢源浓度、最大公用工程节省量、储氢材料量和吸氢时间。用该方法对某炼厂氢网络和储氢提纯单元进行优化,结果表明,最优提纯氢源浓度为70%,提纯后公用工程可节省23.72%; LaNi4.85Al0.15作为储氢提纯材料优于LaNi4.75Fe0.25,其消耗量为991.26kg。 相似文献
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针对高含硫天然气净化装置运行能耗高的问题,本文建立了高含硫天然气净化过程中各类 值计算方法,并对离子溶液体系的 值计算方法进行了修正,使其适用于酸气吸收过程中醇胺溶液的 值计算。在天然气净化过程模拟软件ProMax建立的净化过程全流程模型的基础上,采用 分析方法对高含硫净化装置的全流程进行用能分析。分析结果表明,净化装置全流程的 效率为54.2%,其中硫黄回收单元和尾气处理单元 效率最高,分别为66.8%和66.1%;脱酸气单元的 损失最高,占全流程总 损失的43.5%,这是由于净化装置处理的原料气中H2S含量很高,需要更大溶剂循环量才能使净化气达到商品气标准,这导致吸收溶剂再生过程的能耗大大增加。本文研究成果可指导高含硫天然气净化装置的用能评价及节能改造。 相似文献
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催化净化是利用催化技术对工艺物流、产品和尾气等进行杂质脱除或产品纯化的过程,是催化科学的重要分支。传统的催化净化技术经过近40年的发展,已臻于成熟,多数技术的研究和技术创新活跃度有所降低,相关产品也进入生命周期的末期,市场竞争激烈,利润下降。催化净化技术更有前景的研究和应用在环境保护领域,尤其是精细化需求的环保领域。催化净化技术未来的发展方向:适应新的更严格排放标准的燃油超深度和低成本精制技术;满足精细化需求的环保技术(如室内空气净化和实验室尾气净化等);同一技术解决不同问题(如用高级氧化技术对烟气同时脱硫和脱硝)或多种技术集成解决同一问题(如催化氧化与相转移技术结合进行柴油精制)。 相似文献
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对某钙基膨润土进行物理提纯试验,确定湿法提纯有利于得到高纯度蒙脱石。车间采用二次旋流分力分级法提纯得到了蒙脱石含量≥95%的提纯精矿,通过物理化学性能测试、XRD、电镜等表征,该提纯土达到了医药蒙脱石要求。 相似文献
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Purification processes are widely used in hydrogen networks of refineries to increase hydrogen reuse. In refineries, hydrogen purification techniques include hydrocarbon, hydrogen sulfide and CO removal units. In addition, light hydrocarbon recovery from the hydrogen source streams can also result in hydrogen purification. In order to simplify the superstructure and mathematical model of hydrogen network integration, the models of different purification processes are unified in this paper, including mass balance and the expressions for hydrogen recovery and impurity removal ratios, which are given for all the purification units in refineries. Based on the proposed unified model, a superstructure of hydrogen networks with purification processes is constructed. 相似文献
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分析了湿法磷酸净化的主要技术及特点,介绍了我国湿法磷酸净化技术的产业化情况,提出了湿法磷酸净化技术的发展趋势和展望。 相似文献
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Yew Joon Tam Morvarid Akhavan Rezaei Mohd Lila Mohd Azmi Abdul Rani Bahaman Sewn Cen Lo 《分离科学与技术》2016,51(5):816-829
Univariate screening on factors affecting the purification performance of recombinant hepatitis B surface antigen (HBsAg) on ion exchange chromatography (IEC) and size exclusion chromatography (SEC) and the establishment of a two-step purification strategy were performed. Amongst four IEC adsorbents examined, the use of Q Sepharose XL IEC adsorbent under optimized conditions together with optimized SEC purification was able to efficiently purify HBsAg. An established purification strategy comprising the two techniques further demonstrated adaptability for scale-up operations with a final total purification factor (PF) of 94.82 ± 16.20, HBsAg purity of 95.48% and recovery yield of 78.07%. 相似文献
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整体煤气化联合循环(IGCC)流程中粗煤气净化系统分为常温湿法净化和高温干法净化,着重介绍了净化系统工艺流程中的除尘、脱硫技术及其设备,以及各自的优缺点,并对目前IGCC电站的粗煤气净化工艺和设备选择提出了建议。 相似文献