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71.
Polytrimethylpropyne supported on a solid substrate was proposed as a chromatographic adsorbent for the separation of hydrocarbon gases. The heats of adsorption of hydrocarbon gases were determined. The efficiency of application of this sorbent for the selective separation of C1--C4 hydrocarbon gases in packed columns was demonstrated. 相似文献
72.
Kharitonov A. B. Fomkin A. A. Pribylov A. A. Sinitsyn V. A. 《Russian Chemical Bulletin》2001,50(4):591-594
Carbon dioxide adsorption on the microporous carbon adsorbent PAU-10 within the 177.8—423 K temperature and 0.1—5.13·106 Pa pressure intervals was studied. The isosteres of absolute adsorption are well approximated by straight lines, which do not change their slope on going to temperatures higher than the critical temperature of CO2. An increase in the differential molar isosteric heat of adsorption (q
st) at 0 < a < 1 mmol g–1 is explained by the influence of the endothermic effect of adsorption expansion of the adsorbent. In the region of high pressures and nonideal gas phase, q
st is temperature-dependent. 相似文献
73.
74.
SHI Zuoqing XU Mancai LIN Xue XU Mingcheng FAN Yunge SHI Rongfu YANG Yizhong HE Binglin 《Chinese Journal of Reactive Polymers》2000,(1)
1 INTRODUCTIONPhenol and many substitUted phenols, such as nitrophenols, chlorophenols and aminophenolset al, are the common organic pollutantS existing in wane water of many chemical plants.Treatment of the wastewater containing phenols is an important project for environmentprotection and has been studied by various methods, such as dialysis ['l, microbial degradation ['1,oxidation l'l, extracting with solvents I4] and adsorption with polymeric adsorbents IS]. Theadsorption method is v… 相似文献
75.
Composite adsorbents of carbon and alumina intercalated montmorillonite were prepared and characterized by adsorption of N2and O2at various temperatures. The effects of pyrolysis, temperature, heating rate, subsequent degassing, and doping of cations and anions were investigated. The adsorption capacities of the composite adsorbents developed at higher temperatures (0 and −79°C) are found to be larger than those of normal alumina pillared clays. The experimental results showed that the framework of these adsorbents is made of alumina particles and clay sheets while the pyrolyzed carbon distributes in the space of interlayers and interpillars. The pores between the carbon particles, clay sheets, and alumina pillars are very narrow with very strong adsorption forces, leading to enhanced adsorption capacities at 0 and −79°C. The composite adsorbents exhibit features similar to those of carbonaceous adsorbents. Their pore structures, adsorption capacities, and selectivities to oxygen can be tailored by a controlled degassing procedure. Meanwhile, ions can be doped into the adsorbents to modify their adsorption properties, as usually observed for oxide adsorbents like zeolite and pillared clays. Such flexibility in pore structure tailoring is a potential advantage of the composite adsorbents developed for their adsorption and separation applications. 相似文献
76.
77.
The adsorptive capacity and selectivity of a novel adsorbent with pyridyl group toward stevia glycosides were studied. The effect of polarity and physical structure of the sorbent on the selectivity was investigated in detail. Two separation methods were applied in the enrichment of rebaudioside A(RA). They were selective elution using methanol or ethanol solution as solvent, and dynamic chromatographic separation using pyridyl resin with high selectivity. Results show that the chromatographic separation method can effectively enrich RA from stevia glycoside with high content of stevioside. 相似文献
78.
79.
由大孔氯甲基化聚苯乙烯合成了含有悬挂醚键的甲氧基修饰的大孔交联树脂.通过化学分析(氯含量的测定)、红外光谱和元素分析等手段,确证甲氧基负载在聚苯乙烯骨架上,负载量为4.10mmol/g.测定了这种树脂对正己烷中苯酚的吸附等温线,表明其对正己烷中苯酚的吸附是放热的,随着温度的升高,吸附量逐渐降低,且吸附等温线可拟合成直线.通过吸附焓的计算、不同条件下吸附等温线的比较以及理论计算等方法,确证氢键是甲氧基修饰的大孔交联树脂吸附正己烷中苯酚的主要驱动力,树脂骨架上负载的醚氧原子与苯酚的酚羟基氢原子形成了强烈氢键. 相似文献
80.
用MnO_2离子筛吸附剂从溶液中提取锂(英文) 总被引:1,自引:0,他引:1
研究了MnO2离子筛的制备、表征及其提锂性能。通过控制低温水热合成反应条件制备了4种不同晶相的一维纳米MnO2,进一步用浸渍法制备了Li-Mn-O三元氧化物前驱体,并经酸处理后得到对Li+具有特殊选择性的离子筛。用XRD、吸附等温线、吸附动力学及pH滴定等手段对产物的晶相结构和Li+吸附性能进行了研究。结果表明,SMO-b和SMO-d离子筛的Li+平衡吸附量符合Freundlich吸附等温方程。反应物浓度对MnO2不同晶面的生长速率有不同的影响,但(NH4)2SO4对吸附容量并无提高。吸附速率方程符合一级动力学Lagergren方程。MnO2离子筛Li+的吸附量远远高于Na+。 相似文献