排序方式: 共有14条查询结果,搜索用时 218 毫秒
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从硫化特性、热变形值、凝胶质量分数和物理性能等方面考察了四亚乙基五胺(TEPA)对PVC和PVC/NBR共混物的交联作用以及PVC和NBR同时交联对共混物性能的影响。结果表明,PVC/NBR共混物中的PVC组分交联后,共混物的物理性能和热变形性能都有所改善;PVC和NBR两组分同时交联可改善共混物的物理性能和热变形性能,在NBR用量较大(60份以上)时效果更为明显,若NBR用量太低,则共混物热变形性能反而有所下降;交联剂TEPA对硫黄硫化NBR有一定抑制作用,对共混物的物理性能影响不大,但在一定用量范围内有较小的劣化作用 相似文献
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PVC‐TEPA‐supported L ‐proline catalyst has been synthesized and characterized by IR. It is developed as an efficient catalyst for the direct asymmetric aldol reaction of unmodified ketones with various aldehydes in the presence of water at 0°C. The corresponding aldol products were obtained with high yields (up to 94%) and good enantioselectivities (up to 97% ee) on optimized conditions. Recycling investigations have shown that this material can be reused without loss of catalytic activity and stereoselectivity for at least 15 cycles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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以九水硝酸铝为铝源,非表面活性剂柠檬酸为模板剂,稀氨水为沉淀剂合成有序介孔氧化铝( OMA)。以四乙烯五胺( TEPA)为活性组分,采用物理浸渍将其负载到OMA的内孔及比表面上,制备出氨基功能化的OMA用于CO2的选择吸附研究。采用XRD、BET和TEM对合成的吸附剂进行表征,通过自制的固定床反应器测量穿透曲线的方法研究其对CH4/CO2混合气的吸附分离性能。分别考察了负载量和吸附温度对吸附性能和分离因子的影响。结果表明,TEPA负载量为50%的吸附剂、吸附温度为70℃时对CO2吸附量最大,为2.598 mmol/g,TEPA/OMA经过10次吸附-脱附循环后,其吸附性能变化较小,仅下降了8.65%,具有较好的循环稳定性。 相似文献
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酸化是油井增产、水井增注的重要措施之一.在酸化施工中,所使用的常规酸液,如盐酸与土酸对灰岩和砂岩地层的酸化,由于酸、岩反应速度快,酸的作用距离短,只能消除近井地层的堵塞,达不到疏通深部地层通道从而增产的目的.甚至容易造成近井地带过度酸化,引起溶洞或出砂,破坏地层渗透性,严重影响油井增产、水井增注效果.为此,以不同的原料为起始剂,研制出了系列聚氧丙烯聚氧乙烯醚,筛选出了符合要求的酸化缓速剂. 相似文献
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以乙醇胺(MEA)和四乙烯五胺(TEPA)作为吸收剂吸收燃煤烟气中的CO2。在反应温度20℃、溶剂体积浓度5%、CO2体积浓度13%、模拟烟气流量550L/h时,MEA和TEPA的吸收速率分别为0.659和0.513mmol/s。 相似文献
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Ugochukwu E. AronuHallvard F. Svendsen 《Chemical Engineering Research and Design》2011,89(8):1197-1203
A method was developed for selection of promising solvents based on CO2 absorption experiments at 40 °C and 9.5 kPa CO2 partial pressure followed by desorption of the same solvents at 80 °C down to 1.0 kPa CO2 partial pressure. Experiments conducted on 13 solvent systems under atmospheric conditions revealed the solvents absorption and desorption characteristics and these were compared with 1.0 M, 2.5 M, 5.0 M and 10.0 M MEA. Results showed that absorption or stripping data alone were not sufficient in making robust solvent selection decisions, and that combined data analysis was necessary. 1.0 M tetraethylenepentamine (TEPA) and 5.0 M MEA showed the best performance in terms of absorption rate. 1.5 M Bis-(3-dimethylaminopropyl) amine (TMBPA) was easy to desorb, has high absorption capacity; and when promoted it showed the best performance in terms of CO2 carrying capacity. At the test conditions, 1.5 M TMBPA promoted with 1.0 M PZ showed the best potential for efficient CO2 removal at reduced cost of all systems tested. Its cyclic capacity in mol CO2/mol amine was found to be 70% higher than that of 5 M MEA. 相似文献
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CO2 separation performance by chitosan/tetraethylenepentamine/poly(ether sulfone) composite membrane
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CO2 separation from CO2/N2 (20:80) gas mixture has been demonstrated by tetraethylenepentamine blended with chitosan (CS‐TEPA) membrane. Optimization of CS and TEPA weight ratio were carried out based on characterization details involving thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, atomic force microscope, and field emission scanning electron microscope. Effects of water flow rate, pressure, and temperature were concurrently studied on CS‐TEPA membranes through gas permeation. Almost twofold increase in CO2 permeance (24.7 GPU) was detected in CS blend with 30% (w/w) of TEPA (CS70) as compared to pure CS membrane (12.5 GPU). CS70 yielded CO2/N2 selectivity of 80 whereas CS demonstrated a maximum of 54 at 90 °C. The membrane also exhibited improved stability at temperatures less than 120 °C which was evident from TGA isotherm trace. The proposed composite membrane can be a promising candidate for flue gas separation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45206. 相似文献
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以商业煤基活性炭为原料,经低浓度氧气焙烧、H2O2氧化改性,并以四乙烯五胺(TEPA)浸渍,得到胺负载复合氧化活性炭,用于模拟烟道气[(15%(体积)CO2+85%(体积)N2)+10%(体积)H2O]中CO2吸附。低浓度氧气焙烧后,活性炭的最大比表面积和孔体积分别为1421.82 m2/g、0.83 cm3/g。经复合氧化改性后,活性炭的介孔体积增大,表面含氧官能团增加,使得TEPA负载复合氧化活性炭的CO2吸附性能提高。焙烧时间为4 h,H2O2氧化、负载40%TEPA的样品COAC-4-40TEPA,在60℃时CO2饱和吸附量最高为2.45 mmol/g,是TEPA负载未改性活性炭AC-40TEPA的2.02倍。经过十次吸附循环后,COAC-4-40TEPA的 CO2饱和吸附量可维持在92.24%,而TEPA的浸出量仅有0.67%。失活模型研究表明,COAC-4-40TEPA的初始吸附速率常数是AC-40TEPA的1.64倍,且失活速率常数低于AC-40TEPA。 相似文献
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