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氨基膦酸树脂对汞的吸附性能及其机理 总被引:11,自引:0,他引:11
研究了Hg2+在氨基膦酸树脂上的吸附行为。结果表明:静态饱和吸附容量为 581.9mg/g树脂,用0.5mol/L的HCl和0.2~0.3mol/L的EDTA洗脱,洗脱率分别为:97%和99%以上;测得吸附热力学参数分别为: △H=8.45kJ/mol,△G=-3.02kJ/mol,△S= 38.5J/mol稫。等温吸附服从Freundlich经验式;表观活化能Ea=13.6kJ/mol,表观速率常数k298=2.46×10-5/s;树脂功能基与Hg2+的配位比为1∶1;并用化学和红外光谱的方法探讨了树脂对Hg2+的吸附机理。 相似文献
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氨基膦酸树脂对钕(Ⅲ)的吸附性能 总被引:1,自引:0,他引:1
研究了氨基膦酸树脂对钕(Ⅲ)的吸附行为。当pH=5.70时,氨基膦酸树脂对钕(Ⅲ)的静态饱和吸附容量为199.74 mg/g,用1moL/L HCl溶液可以定量洗脱,当T=298 K时,表观吸附速率常数为1.68×10~(-4)s~(-1),吸附热力学参数△H=60.68 kJ/mol,△G=-14.91 kJ/mol,△S=253.65 J/(mol·K),等温吸附服从Freundlich曲线,氨基膦酸树脂功能基与钕(Ⅲ)的配位比为2:1。用红外光谱探讨了氨基膦酸树脂与钕(Ⅲ)的成键情况。 相似文献
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研究了D160大孔吸附树脂对染料木黄酮的吸附性能.结果表明,在pH4.00时,该树脂对染料木黄酮有较好的吸附性能;静态饱和吸附容量为64.5mg/g树脂;用95%乙醇溶液作解吸剂,二次累计解吸率接近100%;表现速率常数k298=1.01×10-4s-1;测得吸附热力学参数分别为:△H=32.2kJ/mol,△S=119J/(mol·K),△G288=-2.03kJ/mol,△G298=-3.22kJ/mol,△G308=4.41kJ/mol.等温吸附服从Freundlich和Langmuir等温吸附规律;研究还表明,提高振荡频率对吸附有利. 相似文献
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共振二胺树脂吸附铂的行为及热力学性质 总被引:3,自引:0,他引:3
测定了共振二胺树脂吸附铂的活化能E_a=2908kJ/mol、热焓△H=-17.23kJ/mol,自由能文化△G~(298)=-33.1kJ/mol.熵变△S~(298)=168J/mol·K。讨论了吸附行为。树脂吸附铂的摩尔比(功能基/Pt(Ⅳ)~2),树脂吸附铂的反应符合Freundlich等温吸附式。用硫脲-盐酸-乙醇水溶液能定量脱洗吸附在树脂上的Pt(Ⅳ),且树脂可再生使用。利用此树脂从含铂废催化剂中回收纯铂获初步成功。 相似文献
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D301大孔树脂吸附钒(V)的性能研究 总被引:3,自引:0,他引:3
研究了D301大孔树脂对钒的吸附性能.结果表明,pH值对D301树脂吸附钒的影响很大,与钒在溶液中的赋存状态有关,且在pH=2时吸附效果最好:测得吸附热力学参数分别为:△H=8.97kJ/mol,△G_(313)=-5.69kJ/mol,△G_(303)=-5.2kJ/mol,△G_(293)=-4.9kJ/mol,△S=46.84J/mol·K.等温吸附服从Freundlich经验式;考察了溶液浓度、搅拌速率对交换过程的影响,并对实验数据运用相关理论模型进行拟合,结果显示钒(V)在D301树脂上吸附交换过程控制步骤为颗粒扩散控制,反应级数n为0.2391. 相似文献
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研究了717型阴离子交换树脂对苯酚、苯甲酸和十二烷基苯磺酸钠(SDBS)等水溶性芳香族污染物吸附过程的基本化学问题.研究结果表明:717型树脂对苯酚、苯甲酸和SDBS的吸附过程均符合Lagergren二级吸附动力学方程,吸附速率均随着温度的升高而加快,吸附表观活化能Ea分别为13.2kJ/mol、59.5kJ/mol和48.1kJ/mol,吸附过程△H0和△S0均为正值,△G0均为负值,吸附能够自发进行;吸附等温模型符合Langmuir等温式;318K时,717型树脂在pH=9.1对SDBS的饱和吸附容量为360mg/g;在pH=10.2,对苯酚和苯甲酸的饱和吸附容量分别为194mg/g和286mg/g.用浓度均为0.5mol/L,体积比为5∶1的NaCl-NaOH混合溶液可快速洗脱树脂上吸附的污染物,洗脱率达98%以上.该树脂对水溶性芳香族污染物吸附容量大,易于再生和循环利用,可用于环境水体中水溶性芳香族有机污染物的吸附治理. 相似文献
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A new method for the determination of adsorption space volume has been proposed, which is applicable to adsorbents with an arbitrary porous structure, including nonporous adsorbents with open surfaces. The method is based on the use of an experimental excess adsorption isotherm measured over a wide range of pressures in the equilibrium gaseous phase (as a rule up to 100–150 MPa) and the absolute adsorption isotherm equation with unspecified parameters in the most general form, given by statistical physics. The method has been tested for a number of adsorption systems, and it has been found that the result was always unambiguous, correct, and stable in the sense of input data.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2381–2385, December, 1995. 相似文献
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Methods for concentrating dilute fluids using adsorption followed by partial thermal regeneration were studied using the simulation package ADSIM. The systems studied were NaCl in liquid water on Amberlite XD-2 resin and benzene vapor in nitrogen on activated carbon. Cycles studied included counter-current regeneration with pure hot fluid, co-current regeneration with pure hot fluid, a new process called Hot Feed Addition (HFA) consisting of co-current regeneration with pure hot fluid followed by hot feed, and cycling zone adsorption (co-current alternating hot and cold feeds with no pure regeneration fluid). The optimum system depends upon the conditions of the system and the value function chosen to evaluate the systems. For example, for benzene in nitrogen with hot regeneration gas at 467.4 K, cycling zone adsorption used no carrier gas, had the most concentrated benzene stream and a very pure nitrogen product, but the energy use was greater than the other processes. For liquid systems counter-current operation could produce the purest product, but regenerant requirements were high. With slightly lower purity requirements HFA reduced solvent usage and increased the concentration of the concentrated waste stream. For the liquid system all processes used approximately 3% or less of the energy that would be required for evaporation. 相似文献
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大孔吸附树脂的吸附机理 总被引:3,自引:0,他引:3
大孔吸附树脂(macroprous adsorption resin, MAR)是近几十年发展起来的一种具有多孔立体结构、人工合成的有机高分子聚合物。由于其特殊的理化性质和吸附性能,已被广泛应用于化学、医药、环保和食品等领域。本文介绍了近年来国内外对大孔吸附树脂在吸附机理研究方面的进展,重点介绍了不同温度条件下大孔吸附树脂对靶标分子的吸附热力学行为模式,靶标分子在大孔吸附树脂表面及孔内的吸附扩散行为模式。此外,大孔吸附树脂性能参数和靶标分子结构参数之间构效关系也对其吸附选择性规律具有重要的影响。因此,大孔吸附树脂与底物间构效关系的匹配程度及其对选择性的影响是大孔吸附树脂分离理论研究的核心。本文最后介绍了可以准确客观描述吸附过程并具有一定使用范围的大孔吸附树脂吸附模型的建立和评价。 相似文献
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氨基酸在固/液界面的吸附作用 总被引:7,自引:0,他引:7
本文介绍了氨基酸在固/液界面吸附等温线的特点,氨基酸液相吸附热力学和活性炭、硅胶、二氧化钛、氧化铝、蒙脱土等自水中吸附氨基酸的机制。 相似文献
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Thermodynamic analysis of the adsorption Temkin isotherm was performed. The equations that describe the dependence of the thermodynamic functions on the amount adsorbed were obtained. A relationship between the excess differential and mean molar thermodynamic functions was found. The thermodynamic approach does not contradict the molecular statistical theory and appears to be more general. 相似文献
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A. V. Tvardovskii 《Russian Chemical Bulletin》1992,41(4):603-607
The Brunauer-Emmett-Teller (BET) and Frenkel-Halsey-Hill equations are shown to be special cases of an equation obtained earlier for interphase equilibrium.Institute of Physical Chemistry, Russian Academy of Sciences, Moscow 117915. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 779–785, April, 1992. 相似文献
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To study the mechanism of physical adsorption of supercritical gases, the adsorption equilibria of N2 on silica gel for 103–298 K using 20 K increments and pressures up to 10 MPa were measured. A transition of the adsorption mechanism was proven on crossing the critical temperature, but the transition way observed is different from that observed with activated carbon. This causes a difference in the locations of the linear section of the n-
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isotherm at the near-critical temperature. Although the isotherm type is different on silica gel and on activated carbon in the sub-critical region, all isotherms in the supercritical region can be well modeled by a single model. It leads to the argument that the adsorption mechanism of supercritical gases is identical no matter what kind of adsorbent is used. 相似文献
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Jan Kornatowski 《Adsorption》2005,11(3-4):275-293
This critical review concerns the author's results and experience in adsorption studies on molecular sieves comprising crystalline
microporous aluminosilicates and aluminophosphates as well as amorphous mesoporous aluminosilicates. The discussion is mainly
based on three distinctly different standard adsorbates: nitrogen, benzene, and water. The highlights or advantages and the
shortcomings or limitations are considered from the points of view of the experimental procedures and expressiveness or concluding.
The results are compared to several other zeolitic materials and adsorbates. Adsorption technique is a valuable tool for characterization
of the molecular sieves. Since the measurements are very sensitive to modification of the materials, the investigations require
sufficiently thorough procedures and the results a careful interpretation. A comparison between the results for larger series
of materials yields valuable conclusions that are much more expressive than those from a single measurement or material.
Dedicated to the memory of Professor Wolfgang Schirmer. 相似文献