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《膜科学与技术》2021,41(4)
将微滤、超滤膜技术应用于康妇炎胶囊制剂二次开发中的分离纯化操作单元,研究其替代传统醇沉法的可行性.以康妇炎胶囊制剂中药水提液及其中间体干浸膏的理化性质为考察指标,分析比较膜技术与醇沉法的分离纯化效果;同时考察膜操作条件对膜通量及膜污染的影响.结果表明,经膜技术分离纯化后,康妇炎胶囊制剂中药水提液的浊度、黏度等均有不同程度的降低.在杂质整体去除方面,醇沉法优于膜技术;而在有效成分保留方面,膜技术优于醇沉法.同时,膜技术可降低康妇炎胶囊制剂中药干膏粉的吸湿性,提高了干膏粉的稳定性.跨膜压差、料液流速等工艺参数对膜通量及膜污染具有重要影响,需通过工艺优化,确定适宜的膜工艺参数.根据以上研究结果与分析,将膜技术应用于康妇炎胶囊制剂二次开发中的分离纯化操作单元具有一定的适宜性、可行性. 相似文献
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稀有气体通常利用沸点的差异进行深冷分离,相对于这种传统方法,膜技术具有高效、低耗和环保等优异性能.在膜技术中,膜材料的选择及其后处理是影响气体分离效果的重要因素.选择两种不同聚酰亚胺,PI-1 (BTDA-MDA/TDA)和PI-2 (PMDA/BTDA-TDA),研究了其单体结构对于稀有气体分离性能的影响.在此基础上选择性能较为优异的PI-2膜进行不同条件的热处理,研究热处理温度对其气体分离性能的影响.研究发现,通过改变聚酰亚胺的共聚组成,可以调节分离膜的气体选择性与渗透性.热处理会改变膜内分子链堆积、部分膜结构的生成或消失以及去除残余溶剂的塑化作用,进而改变膜的渗透分离性能.通过控制热处理条件,可以使膜的渗透性与选择性同时提升,He渗透系数增加至19.1 Barrer, He/CH4选择性提高了54%,O2/Xe选择性提升99%. 相似文献
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以烟道气中CO2的捕集为研究背景,以聚醚共聚酰胺Pebax1657嵌段共聚物为选择层膜材料,采用浸渍涂覆法,制备具有超薄分离皮层的PEI/PDMS/Pebax1657/PDMS多层复合气体分离膜,研究复合气体分离膜对CO2/N2混合气的分离特性.由于CO2的增塑作用,复合膜对CO2/N2混合气的分离系数为40左右,低于其理想分离系数.操作压力和原料气中CO2浓度对复合膜的渗透分离性能以及混合气的分离效果影响显著.在实际应用中,可通过调节膜两侧操作压力来提高CO2的富集浓度. 相似文献
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聚醚共聚酰胺复合气体分离膜的制备与分离性能 总被引:1,自引:0,他引:1
以湿涂方式,采用浸渍涂层方法,通过溶剂蒸发制得聚醚共聚酰胺PEBA2533平板复合气体分离膜,探讨了在复合膜制备过程中,涂层液溶剂的选择、底膜、涂层浓度、涂层温度以及固化干燥时间等因素对CO2/N2体系渗透分离性能的影响.正丙醇和水的互溶性导致了大量表面缺陷的形成,使得以正丙醇为溶剂制得的复合气体分离膜对CO2/N2体系没有选择性.以正丁醇做溶剂,涂层质量分数大于5%时,形成具有致密分离层的复合气体分离膜,CO2/N2分离系数达到本征分离性能.涂层温度的升高促使复合膜表面缺陷的增加,导致CO2/N2的分离系数减小. 相似文献
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Many investigations have conducted life cycle assessments (LCA) of the most commonly discussed routes of carbon capture and storage (CCS): post-combustion with amine wash separation; oxyfuel using cryogenic air separation and pre-combustion by integrated gasification combined cycle (IGCC) using physical separation. A research alliance developed corresponding separation systems using different types of membranes to allow a more energy efficient separation process: polyactive polymeric membranes for post-combustion, ceramic membranes for oxyfuel and metallic membranes for IGCC separation. By conducting an LCA, the study examines the actual greenhouse gas emissions and other environmental impacts of the new membrane separation technologies, together with concepts implementing the more common technologies. The reference systems represent today’s state-of-the-art supercritical coal fired power plant in Germany, together with a more advanced ultra-supercritical plant operating at 700 °C without CO2 capture. The results demonstrate that among the three reference power plants the IGCC is the superior concept due to the highest efficiency. Regarding climate change, the IGCC power plants with CO2 capture are still the best concepts. When other environmental impacts are considered, the capture technologies are inferior. The membrane concepts show the overall better results in comparison to the conventional capture technologies. The environmental impacts for membrane applications add a new range of findings to the field of CCS LCAs. Now the results for several different approaches can be compared directly for the first time. 相似文献
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Xuezhong He 《工程(英文)》2021,7(1):124-131
Carbon dioxide(CO2)capture by gas-separation membranes has become increasingly attractive due to its high energy efficiency,relatively low cost,and environmenta... 相似文献
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新型CO2捕获材料研究进展 总被引:1,自引:0,他引:1
高效、经济、环境友好的CO2捕获技术的开发与应用将是未来发展的趋势.本文概括了对CO2的吸附分离技术以及捕获机理,总结了传统CO2捕获材料的研究与不足,重点讨论了新型CO2捕获材料的发展状况和研究进展,新型CO2捕获材料的研发与应用将大大缓解全球气候变暖. 相似文献
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One of the new approaches for capturing carbon dioxide from treated flue gases (post-combustion capture) is based on gas hydrate crystallization. The basis for the separation or capture of the CO(2) is the fact that the carbon dioxide content of gas hydrate crystals is different than that of the flue gas. When a gas mixture of CO(2) and H(2) forms gas hydrates the CO(2) prefers to partition in the hydrate phase. This provides the basis for the separation of CO(2) (pre-combustion capture) from a fuel gas (CO(2)/H(2)) mixture. The present study illustrates the concept and provides basic thermodynamic and kinetic data for conceptual process design. In addition, hybrid conceptual processes for pre and post-combustion capture based on hydrate formation coupled with membrane separation are presented. 相似文献
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CO2/CH4醋酸纤维素分离膜的制备 总被引:3,自引:0,他引:3
以湿相转化法制备CO2/C4醋酸纤维互分离膜,无需热处理工序,研究了各种制膜条件,如蒸发时间、聚合物芨添加剂含量等,对膜气体分离性能的影响;用电镜观察了膜的形态结构,结果表明,适当提高聚合物浓度和延长蒸发时间可使膜表皮层变致密,获得高的CO2/CH4分离选择性和气体透过速率。 相似文献
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为制备C60含量不同的乙基纤维素(EC)/C60复合膜,采用UV-可见光谱、AFM和XRD等手段对紫外光辐照前后复合膜结构进行表征,并考察其对气体分离及渗透性能的影响.结果表明,复合膜经紫外光辐照后,C60在膜表面的分布由独立的簇状结构转变为连续平缓的丘陵状结构,膜表面更加致密光滑;复合膜分子链间距未发生明显变化,但对N2、CO2、H2的渗透性能和H2/N2、CO2/N2分离性能产生明显影响.当C60添加量达到1.6%时,未经紫外光辐照的复合膜对CO2及H2的透气系数较纯EC膜分别提高了30%和40%,分别达到61.29Barrer和78.88Barrer,对H2/N2,CO2/N2理想分离系数增至纯EC膜的1.47和1.38倍,分别达到9.979和12.84;经紫外光辐照后,高C60含量的EC/C60复合膜能够保持纯EC膜对CO2和H2的透过水平,而对H2/N2和CO2/N2的分离性能增至纯EC膜的2.30和2.43倍,分别达到17.49和25.60. 相似文献
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Binghong Chen Hongli Xie Liguo Shen Yanchao Xu Meijia Zhang Mingzhu Zhou Bisheng Li Renjie Li Hongjun Lin 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(17):2207313
Membrane-based carbon dioxide (CO2) capture and separation technologies have aroused great interest in industry and academia due to their great potential to combat current global warming, reduce energy consumption in chemical separation of raw materials, and achieve carbon neutrality. The emerging covalent organic frameworks (COFs) composed of organic linkers via reversible covalent bonds are a class of porous crystalline polymers with regular and extended structures. The inherent structure and customizable organic linkers give COFs high and permanent porosity, short transport channel, tunable functionality, and excellent stability, thereby enabling them rising-star alternatives for developing advanced CO2 separation membranes. Therefore, the promising research areas ranging from development of COF membranes to their separation applications have emerged. Herein, this review first introduces the main advantages of COFs as the state-of-the-art membranes in CO2 separation, including tunable pore size, modifiable surfaces property, adjustable surface charge, excellent stability. Then, the preparation approaches of COF-based membranes are systematically summarized, including in situ growth, layer-by-layer stacking, blending, and interface engineering. Subsequently, the key advances of COF-based membranes in separating various CO2 mixed gases, such as CO2/CH4, CO2/H2, CO2/N2, and CO2/He, are comprehensively discussed. Finally, the current issues and further research expectations in this field are proposed. 相似文献
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碳捕获与封存技术是一种具有前景的CO2减排策略。本工作采用巨正则蒙特卡洛模拟研究了温度为298 K、压强在0~5 kPa范围内三种混合超微孔材料SIFSIX-X-Cu(以SiF6 2-排列, Cu为金属中心, X=2, 3, O)中CO2/N2吸附与分离的行为。结果显示, 相比于SIFSIX-2-Cu, SIFSIX-3-Cu和SIFSIX-O-Cu中CO2在0.5 kPa就达到吸附饱和, 且在1 kPa下的吸附量分别达到了2.70与2.39 mmol·g -1。CO2/N2混合气体中CO2的吸附量几乎没有下降。SIFSIX-3-Cu和SIFSIX-O-Cu具有接近于CO2分子动力学直径的孔径, 对CO2亲和力较大, 吸附热分别达到了59和66 kJ·mol -1。密度泛函理论分析发现, 在两种结构中每个孔隙只吸附一个CO2分子, 且几乎处于孔道的中心。本工作为低压下吸附与分离CO2的混合超微孔材料的开发提供了理论指导。 相似文献