两性树脂吸附低浓度游离酸

利用电导实验技术，跟踪观察两性离子交换树脂吸附低浓度游离酸的行为。实验结果表明，两性树脂吸附低浓度游离酸时，表现吸附速率常数随吸附质浓度的增大而降低，吸附过程是遵循单分子层机制的行为。     

电导法研究D252树脂吸附低浓度游离酸的行为

利用电导技术研究D252大孔离子交换树脂吸附低浓度游离酸的行为。实验结果表明：随着吸附质浓度的增大．表观吸附速率常数K逐渐减小;吸附质与吸附剂之间的相互作用能逐渐减小;吸附质对吸附剂的亲和能也逐渐减小。     

两性树脂吸附低浓度游离酸

利用电导实验技术 ,跟踪观察两性离子交换树脂吸附低浓度游离酸的行为。实验结果表明 ,两性树脂吸附低浓度游离酸时 ,表观吸附速率常数随吸附质浓度的增大而降低 ,吸附过程是遵循单分子层机制的行为。     

电导法研究固—液界面的吸附：D354树脂吸附低浓度游离酸的行为

利用电导实验技术,跟踪观察３５４树脂吸附低浓度游离酸的行为,研究吸附体系的性质对吸附的影响。实验结果表明,Ｄ３５４树脂吸附低浓度游离的吸附速度大小顺序为ＨＣｌＯ４〉ＨＮＯ３〉ＨＣｌ。Ｄ３５４树脂的吸附活性中心是自由胺基。     

弱酸性树脂吸附低浓度游离碱行为的研究

利用电导实验技术 ,跟踪观察弱酸性树脂吸附低浓度游离碱的行为 ,研究温度对吸附的影响 ,测定吸附活化能 ( Ea)和吸附剂 -吸附质相互作用能 ( U)。实验结果表明 ,温度升高 ,吸附剂 -吸附质相互作用能增加 ,表观吸附速率常数 ( k)增大 ,而且 U与 T存在良好的线性相关 ( r=0 .995 1 )     

介质对交联壳聚糖树脂吸附的影响

利用电导实验技术，跟踪观察交联壳聚糖树脂吸附游离酸的行为。讨论介质对吸附的影响。利用固-液相互作用方程，求取吸附剂-吸附质相互作用能。实验结果表明，表观吸附速率常数随着外加离子强度的增大而减少。     

电位法研究弱碱性树脂吸附稀醋酸的行为

利用电位法实验技术跟踪观察弱碱性树脂吸附低浓度醋酸溶液的过程,讨论了酸浓度和外加盐对吸附的影响.利用固-液界面吸附动力学方程,求取表观吸附速率常数(k).实验结果表明,弱碱性树脂上吸附低浓度醋酸的过程是遵循单分子层机制进行的,表现吸附速率常数(k)随着酯酸浓度的增大而减少;在固定醋酸浓度时,表现吸附速率常数(k)随着外加盐离子浓度的增大而增大.     

可再生甲壳质吸附特性研究进展

本文综述了可再生甲壳质吸附特性研究的概况,介绍了可再生甲壳质吸附阴离子染料、有机酸、Cr~(6 )、低浓度无机酸等特性。     

732型阳离子交换树脂吸附L-色氨酸的性能研究

在线跟踪观察732型阳离子树脂吸附L-色氨酸的行为。实验结果表明,732型阳离子树脂吸附L-色氨酸速率由液膜扩散控制,表观吸附速率常数,随温度的升高而增大,其表观活化能Ea为30．46kJ／mol;表观吸附速率常数随体系中葡萄糖含量的增大而减小;外加氯化钠导致两种竞争,低浓度有利于树脂对L-色氨酸的吸附。     

电位分析法用于可再生甲壳质对Cu2+吸附的动力学研究

首次利用铜离子选择性电极，跟踪观察了可再生甲壳质吸附Cu^2 的动力这行为。实验结果表明，可再生甲壳质中的氨基作为配体，与Cu^2 具有良好的螯合作用，随着Cu^2 浓度的增加，吸附速度减慢，吸附剂与吸附质间的相互作用力降低，表观吸附速率常数减少。以铜离子选择性电极作为吸附质分子探针的电位分析技术，电极具有良好的能斯特响应，相关系数达0．994，系统具有良好的重现性和稳定性，可用于Cu^2 的在线追踪以进行吸附动力学研究，这为固－液吸附的动力学研究提供一新的方法和手段。     

壳聚糖超细纤维的制备及其铬离子吸附性能研究

利用静电纺丝和热交联技术,制备了良好形貌的交联壳聚糖/聚甲基丙烯酸(CS/PMAA)纤维膜,然后采用正丙醛化学改性得到改性CS/PMAA纤维膜。Cr(Ⅵ)离子吸附实验发现,铬元素浓度为6.50 mg/L时,CS/PMAA纤维膜的吸附量可以达到4.98 mg/g;而当铬元素浓度为3.75 mg/L时,铬的去除率可以达到81.0%;而且提高壳聚糖的含量有利于提高CS/PMAA纤维膜的吸附性能。改性CS/PMAA纤维膜吸附结果显示,正丙醛改性CS/PMAA纤维膜降低吸附性能,而进一步还原后的纤维膜的吸附性能优于未改性CS/PMAA纤维膜。实验结果表明,CS/PMAA纤维膜对铬离子具有良好的吸附性能;CS/PMAA纤维膜的吸附性能主要通过纤维氨基与Cr2O72-的相互作用进行,提高氨基的碱性和数量有利于提高纤维膜的吸附性能。     

Removal of endocrine disrupting chemicals from contaminated industrial groundwater using chitin as a biosorbent

BACKGROUND: The removal of endocrine disrupting chemicals (EDCs) from drinking water is of great importance. Chitin isolated from crab shells was used as a biosorbent for removal of three EDCs—benzo(a)antracene, β‐estradiol and bisphenol A—present in contaminated groundwater. Fourier transform infra‐red (FTIR) spectroscopy, porosimetry and scanning electron microscope (SEM) were used for structural elucidation of chitin. Experiments were conducted using batch adsorption mode under different conditions of initial EDCs concentration, solution pH and adsorbent dose. The effect of chitin particle size was also investigated. Batch adsorption data were fitted to Langmuir and Freundlich isotherms and pseudo‐first‐ and second‐order models for kinetic study. RESULTS: The maximum adsorption capacity of chitin by the three EDCs, calculated using the Langmuir equation, ranged from 42.9 to 84 mg g^?1. The adsorption of EDCs by chitin was due primarily to electrostatic forces. The measurement of zeta potential indicated that chitin has higher surface charge in alkaline pH, resulting in reduction in removal of EDCs with increasing pH. Complementary to the experimental results molecular simulations were also performed on HyperChem software to understand the adsorption mechanism between chitin and EDCs in aquesous solutions. Chitin was regenerated after washing with methanol/acetic acid (1/3, v/v) and the regeneration process was repeated for 10 cycles, which showed 90% adsorption capacity retained by chitin. CONCLUSIONS: The experimental results suggest that chitin could be employed as an adsorbent in the removal of EDCs from aqueous solutions, and the adsorption potential of used chitin can be recovered by methanol/acetic acid solvent washings. The reusable biosorbent chitin would be cost‐effective and a better option for future water remediation endeavours. Copyright © 2010 Society of Chemical Industry     

Synthesis of sulfhydryl chitin and its adsorption properties for heavy metal ions

This article discusses the preparation of the water‐insoluble adsorbent sulfhydryl chitin (s‐chitin), by treatment of the chitin with sulfhydryl acetic acid in the presence of sulfuric acid as a catalyst. Its structure was confirmed by elemental analysis, FTIR spectra analysis and near‐IR spectra analysis. We also investigated the adsorption properties of sulfhydryl chitin for Cu^II, Cd^II, Pb^II, Cr^III, and Ni^II. Based on the research results of adsorption capacity, the effect of pH value on adsorption, adsorption kinetics experiments, and selective adsorption experiments were observed. It has been shown that the s‐chitin has much better adsorption for Pb^II, Cu^II, and Cd^II than chitin itself. The adsorption capacities of s‐chitin for Pb^II, Cu^II, and Cd^II were 108.3, 94.7, and 57.1 mg/g, respectively. It also had good adsorption properties for heavy metal ions. The adsorption capacities were also affected by the acidity of medium. The adsorbed Cu^II, Cd^II, and Pb^II could be eluted by diluted chlorhydric acid. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 151–155, 2000     

Preparation and adsorption properties for metal ions of chitin modified by L‐cysteine

A new adsorbent for heavy metal ions, cys‐chitin, was produced by modifying chitin in THF with L ‐cysteine in the presence of sulfuric acid as a catalyst. Its structure was confirmed by elemental analysis and FTIR spectra analysis. The adsorption properties of cys‐chitin for Cu^II, Cd^II, Pb^II, Zn^II, and Ni^II were investigated. The effect of pH value on adsorption and adsorption kinetics was examined. The results indicate that the cys‐chitin has much better adsorption for Cd^II, Pb^II, and Zn^II than chitin itself. The adsorption capacities of cys‐chitin for Cd^II, Pb^II, and Zn^II were 214.6, 351.5, and 107.0 mg/g, respectively. It also had good adsorption properties for heavy metal ions. The adsorption capacities were also affected by the acidity of medium. The adsorbed Cd^II, Pb^II could be eluted by diluted nitric acid. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2575–2579, 2003     

水对胺改性吸附剂吸附分离CO_2的影响

针对燃煤电厂烟道气中CO2的捕集,采用变压吸附法,从穿透时间、吸附量、分离因子、氨基利用率等方面研究了TEA(三乙醇胺)负载率对胺改性硅胶吸附分离CO2的影响,并进一步考察了胺改性吸附剂中含水量对CO2分离性能的影响。结果表明:TEA改性硅胶对CO2的选择性增强,TEA负载率越高,分离因子越大,TEA负载率为0.8时的分离因子为3.86,是无负载时1.7倍;水的存在能大幅度增强CO2的吸附,水负载率越高,分离因子越大,水负载率为0.35时的分离因子高达24.50,为无水时的7倍,且常温下吸附剂仍可完全再生并具有良好稳定性;氨基利用率随TEA负载率的增大而降低,随水负载率的增大而增大。     

电位法研究弱碱性树脂D354吸附游离无机酸的行为

以D354弱碱性阴离子交换树脂为吸附剂,吸附低浓度的盐酸、硝酸和硫酸,采用电位法对吸附过程进行在线跟踪,利用固-液界面吸附动力方程,求取表观吸附速率常数.重点研究D354树脂与无机酸在三元体系的固-液吸附行为,讨论了NaCl和KCl作为外加盐对吸附速率的影响,寻找其吸附过程的规律.