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变压吸附技术的应用研究进展1 总被引:7,自引:0,他引:7
变压吸附(PSA)技术是近几十年来在工业上新崛起的气体分离技术,是物理化学渗流理论在工业上的具体应用。自上世纪70年代以来,变压吸附技术因其优势明显,在化工分离中占有重要地位,受到关注和发展。文章简要综述了变压吸附技术的发展里程、理论基础及其研究进展、分离过程的计算机模拟和在国内外工业领域中的应用情况,并对其应用前景进行了展望。 相似文献
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因煤层赋存条件和抽采技术水平限制,导致煤矿抽采瓦斯中甲烷(CH4)浓度偏低,而直接排空处理将造成清洁能源浪费和温室效应加剧,因此研究煤矿瓦斯中CH4提纯利用途径将对煤炭行业节能减排具有重要意义.相比于其它气体分离提纯技术,变压吸附分离技术具有操作简单、能耗低及工业化成熟度高等诸多优势.本文将以变压吸附分离技术提纯CH4为核心,重点论述了近些年吸附剂类型、吸附分离机制和分子动力学模拟等方面的研究进展,然后列举变压吸附提纯CH4工艺优化及工业大规模应用实例,最后结合基础研究和工程应用总结展望了变压吸附技术在CH4提纯领域的发展前景,并指出低浓度瓦斯(<10%CH4)提纯及真空变压吸附技术是为进一步提升煤矿瓦斯利用率而亟需攻坚克难的主要研究方向. 相似文献
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膜吸附反应器(MAR)对饮用水系统中病毒的去除 总被引:1,自引:0,他引:1
以尺寸与人体肠道病毒相近的f2噬菌体作为模型病毒,本研究采用膜吸附反应器(Membrane adsorption reactor,MAR),考察膜分离与纳米TiO2耦合工艺对饮用水中病毒的去除效果.两种不同孔径的PVDF(0.20μm)、PAN(0.05μm)平板膜在自来水体系中对f2噬菌体的截留效果分别为1.88~2.56log和4.78~5.95log,大大超过理论计算值,这与膜具有不规则孔型的重叠筛网状结构直接相关.吸附实验结果表明,纳米TiO2对f2噬菌体的吸附在60min内即可达到吸附平衡,符合Freundlich等温吸附模型qe=27.4·Ce1.24.两组MAR系统对f2噬菌体的总去除率分别高达3.88log与6.40log,这主要是由于纳米TiO2的吸附作用,以及运行中在膜表面形成有效的滤饼层.纳米材料与膜系统的耦合既保持了系统对病毒的高效去除,又实现了纳米颗粒的有效分离回收,操作简单、费用低. 相似文献
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气体超临界吸附研究进展 总被引:17,自引:0,他引:17
综述了近年来国内外学者对超临界气体在固体表面吸附的研究情况。指出了气体在临界温度以上吸附与临界温度以下吸附的不同之处;对现行的关于超临界气体的吸附理论研究进行了讨论,并在此基础上提出了研究中存在的总是及进一步的研究方向。 相似文献
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分子筛膜具有规整的微孔结构(<1 nm), 耐高温高压、 抗有机溶剂, 在液相和气相小分子分离中受到广泛关注. 分子筛膜可以与催化反应耦合于一体构成膜反应器, 使反应过程与组分分离同时进行, 促进反应平衡移动, 达到反应强化的效果. 本文概述了近十年不同类型分子筛膜反应器在催化反应中的应用研究进展, 并对分子筛膜反应器未来的发展趋势进行了展望. 相似文献
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The role of pressure and flow transients caused by strong adsorption on the behavior of gas phase adsorptive reactors was studied using a staged model. The general gas phase reaction A + B C is considered for two cases: (1) the product C is adsorbed and (2) both reactants A and B are adsorbed. Strong adsorption of one or more components causes a decrease in the pressure(s) in the stage(s). The pressure decrease causes variations in the inlet and outlet flow rates and in the case of multiple stages, it causes variations in the flows between tanks. In accordance with Le Chatelier's principle, the pressure decrease aids or inhibits product formation depending on whether there is an increase or decrease in total moles by reaction. Reactant flow into the section where adsorption occurs increases because of increased pressure drop behind the adsorption front. However, the residence time of the reactants behind the adsorption front is lower because of the higher velocity. The flow variations can aid or hinder product formation depending on the specific conditions. Thus, the adsorption-caused pressure variations directly modify reaction rates and product concentrations and, also indirectly, by causing flow variations which affect reaction rates and product concentrations. This study highlights the need to include pressure variations when modeling gas phase adsorptive reactors if adsorption is strong irrespective of the net change in the total moles by reaction. It also demonstrates a method to incorporate axial pressure drop in staged models. 相似文献
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阿霉素的吸附伏安法研究 总被引:5,自引:1,他引:4
阿霉素在0.1mol/L HAc-NaAc底液,富集电位-0.20V,富集时间120s,扫速100mV/s等条件下,于悬汞电极上产生一灵敏的吸附伏安还原峰,峰电位为-0.45BV,峰电流与ADM浓度为1.0×1010^-9-4.0×10^-7mol/L范围内呈线性关系,检测限可达5.0×10^-10mol/L。 相似文献
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A detailed model for the recuperative parametric pumping is presented. The model includes intraparticle mass transfer resistance, axial diffusion and non-linear equilibrium represented by Langmuir equation. The sensitivity studies shows that process performance strongly increases when cycle time increases and
B
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ratio and particle size decreases. It also shows that bottom and top dead volumes do not influence much the process performance. Evolution of the histories of concentrations and temperatures, the bed performance from cycle to cycle and the bed dynamics at the cyclic steady state have been discussed.The model revealed itself as useful to simulate the behavior of the recuperative parametric pumping process and was applied to predict optimal experimental results for the system phenol-water/Duolite ES-861 (Part II). 相似文献
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铅-邻菲罗啉-镉试剂体系极谱法测定铅 总被引:1,自引:0,他引:1
在pH7.1的六次甲基四胺和0.1mol/L的KCl底液中,Pb^2+-phen-Cadion于-0.43V处产生灵敏的极谱波,铅浓度在3×10^-8 ̄1×10^-6mol/L之间与峰电流成良好的线性关系,检测下限可达1×10^-8mol/L,线性回归方程为Iy=565.0 Cx-41.10,相关系数为0.9981。测定废水中铅的标准加入回收率可达96.2% ̄101.7%。 相似文献
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《Analytical letters》2012,45(2):211-223
Abstract The adsorptive stripping voltammetric behaviour of the lectin, phytohemagglutinin, has been optimised with respect to accumulation time, accumulation potential, pulse amplitude, scan rate and drop size. Adsorptive stripping voltammetry has also been used to study the interaction of this protein with nannose, galactose and N-acetyl-D-galactosamine. 相似文献
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Fixed-bed columns containing solid catalysts and adsorbents were employed for simultaneous reaction and separation. The models
developed for butene dehydrogenation reaction were validated with experimental data. The model was then employed for variable
bed configurations with and without the effect of pressure and vacuum swing reaction (PSR and VSR). The models for the mass
and momentum transfer in the catalyst bed and adsorber were solved using orthogonal collocation within the method of lines.
The reactor/separator performances were tested for beds with varying numbers of layers of catalysts and adsorbents arranged
sequentially. The reaction columns behaved as reactor/separators in series. As the number of layers increased, a homogeneous
distribution of the catalyst and adsorbent was approached in the limit. These configurations with variable catalyst/adsorbent
distributions were investigated in terms of product purity, selectivity, conversion, recovery and yield. Improved reactor
performance was observed with pressure and vacuum swing separation systems and in particular with close to well-mixed reactor/separator
configurations. 相似文献
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脱氧核糖核酸变性和损伤的吸附伏安法研究 总被引:2,自引:0,他引:2
本文用汞电极(HMDE)二次导数阴极吸附伏安(SD-AdCSV)和碳电极(GCE、CPE)导数循环伏安(FD-CV)法研究了核酸受热、紫外线、超声波和丝裂霉素C(MMC)作用下的变性作用。在0.1mol/L(K2HPO4+KH2PO4)-0.1mol.L NaCl(pH7.0)底液中,吸附的单股(ss-)和双螺旋(ds-)DNA分别在HMDE上得到特征还原峰P3和P2,和在碳电极上得到氧化峰A。物 相似文献
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铜-乙酰丙酮络合物极谱吸附波 总被引:2,自引:0,他引:2
在pH6.8的磷酸盐介质中,铜(Ⅱ)—乙酰丙酮络合物在单扫示波极谱上于-0.28V(vs.SCE)产生灵敏吸附波,铜的检测限为1×10~(-8)mol/L,常见离子不干扰铜的测定。 相似文献