Implications from protein uptake kinetics onto dextran-grafted Sepharose FF coupled with ion exchange and affinity ligands

Our previous studies have reported the presence of "chain delivery" effects of protein adsorption onto ion exchangers with polymer-grafted ion-exchange groups,such as dextran-grafted and poly(ethylenimine)-modified Sepharose gels.However,it is unclear if the "chain delivery" occurs on affinity adsorption with specific interactions.This work is designed to address this issue.A dextran-grafted Sepharose gel was prepared,and then the matrix was modified using diethylaminoethyl,a typical ion-exchange group,or octapeptide (FYCHWQDE),an affinity ligand for human immunoglobulin G (hIgG) to prepare ion-exchange or affinity adsorbents,respectively.Results of hIgG adsorption showed that the uptake rate represented by the effective diffusivity of hIgG onto the dextran-grafted ion exchangers was obviously enhanced by the dextran grafting,indicating the presence of "chain delivery" of the bound proteins on the charged groups on the dextran chains.By contrast,the effective diffusivity of hIgG changed little as ligand density increased on the dextran-grafted FYCHWQDE adsorbents.Their adsorption capacities decreased and effective diffusivities were not accelerated by the dextran grafting.Thus,this work clarified that grafted dextran could not accelerate hIgG uptake rate on the affinity resins,or in other words,chain delivery did not occur on the specific interaction-based affinity adsorption.     

典型液体危化品吸附材料性能

目前用于典型液体危化品吸附的材料类型主要有树脂型和有机高聚物超细纤维型,两种类型中分别选取甲基丙烯酸酯吸油树脂和聚丙烯纤维吸附材料,对此两种吸附材料的吸附相关特性进行了对比实验研究,包括吸附倍率与时间的关系、吸附选择性以及循环吸附/解吸特性等。结果表明,两种吸附材料吸附甲苯的吸附平衡时间均为4 s左右,其中聚丙烯纤维吸附材料的平衡吸附倍率为17.82 g/g,为甲基丙烯酸酯吸油树脂的2.2倍;两种吸附材料都具有较好的吸附选择性;聚丙烯纤维吸附材料在吸附甲苯后能够通过挤压方式解吸附实现循环使用,平均解吸率在80%以上;甲基丙烯酸酯吸油树脂在吸附甲苯后无法通过挤压方式进行解吸附。实验结果将为基于吸附材料的水面液体危化品回收设备的研发奠定基础。     

多壁碳纳米管嵌入13X/MgCl2复合吸附剂的性能实验

配制了将不同含量的多壁碳纳米管（MWCNT）加入复合吸附剂13X/MgCl₂中制成的新型复合吸附剂,并对其吸附、脱附和导热性能进行了测试。实验结果表明：新型复合吸附剂在闭式200℃脱附完成后,新型复合吸附剂的吸附残余量随着MWCNT含量的升高而减小,13X的吸附残余量是MWCNT含量最高的13X/MgCl₂/MWCNT（CNT-5）复合吸附剂的吸附残余量的2倍,虽然MWCNT的加入不会对13X/MgCl₂复合吸附剂在室温下的吸附性能有影响,CNT-5在开式、闭式的平衡吸附量可以达到0.52 g·g^-1和0.38 g·g^-1,分别是13X吸附量（0.24 g·g^-1）的2.2和1.6倍,但新型复合吸附剂可以脱附更多的水蒸气。新型复合吸附剂的热导率随着MWCNT含量的增大而升高,CNT-5的热导率可以达到0.265 W·m^-1·K^-1,是13X热导率的4.9倍。     

活性白土/壳聚糖复合物吸附剂对果汁的澄清作用研究

利用简便的方法制备了活性白土/壳聚糖复合物吸附剂,并通过红外光谱(FT-IR)、热重(TG)、X-射线衍射(XRD)和透射电镜对所制备的吸附剂进行表征.结果表明,壳聚糖嵌入到活性白土的片层结构中,形成了稳定的复合结构,进而增大了活性白土的片层间距,有利于提高活性白土的吸附性能.活性白土/壳聚糖复合物作为吸附剂,对草莓汁、西瓜汁、橙汁均具有较好的澄清效果.对草莓汁澄清条件为:吸附剂用量为0.02 g,35℃、吸附时间1.5h、pH 5,澄清度为69.36％;对西瓜汁的澄清条件为:吸附剂用量为0.02 g,25℃、吸附时间1.5h、pH 6,澄清度达到98.42％;对橙汁的澄清条件为:吸附剂用量为0.02 g,30℃、吸附时间1h、pH 6,澄清度为61.08％.     

Application of non-fluorescent carbon particles as scavengers for heavy metal ions: A waste utilisation approach

In the preparation of fluorescent carbon nanoparticles, formation of non-fluorescent carbon particles (CPs) as waste matter is indispensible. This work is introducing CPs as adsorbents for some toxic metal ions in aqueous medium. CPs were characterised and their particle size, surface area, porosity, morphology etc. were compared with their parent material (charcoal). The effects of the initial metal ion concentration, contact time and pH on adsorption were undertaken. Adsorption data were evaluated for Langmuir and Freundlich isotherm models. The adsorption capacities (mg/g) of Ni²⁺, Pb²⁺, Zn²⁺, Co^2+, Cd²⁺ and Cu²⁺ were 85, 76, 75, 67, 58 and 46, respectively.     

吸附蒸馏提纯叔丁醇及异丙醇

本文简述了吸附蒸馏的设备和流程，提出了吸附蒸馏过程实现工业化的条件。进行了4A分子筛的沉降和吸附蒸馏方法分离叔丁醇-水及异丙醇-水体系的试验。试验结果表明采用吸附蒸馏方法分离叔丁醇-水及异丙醇-水体系，具有产品纯、收率高、操作容易实现的优点。     

凹凸棒石粘土及在水处理中的应用

凹凸棒石粘土是一种以凹凸棒石为主要成分的天然非金属粘土矿物，它是一种具有独特层链状结构的晶质水合镁铝硅酸盐矿物，具有比表面积大、化学稳定性好、吸附能力强等特征。作者对国内外有关凹凸棒石粘土的文章进行了综述，详细叙述了凹凸棒石粘土的组成和结构以及相应的改性方法，分类讨论了凹凸棒石粘土在水处理中的应用，分析了我国在研究开发过程中存在的问题，并提出了相应的意见和建议。     

石化污泥制备吸附剂及其脱硫机理研究

以石化污泥为原料,采用不同方法制备了烟气脱硫吸附剂,探讨了影响产物吸附性能的因素及吸附机理。得到了石化污泥吸附剂的吸附等温线。结果表明,石化污泥利用热解炭化法制备的烟气脱硫吸附剂性能较好,其吸附过程可用Freundlich模型描述,SO2-O2-N2体系吸附机理主要为物理吸附,SO2-O2-H2O(g)-N2体系SO2发生了催化氧化,以化学吸附为主。     

Adsorption and desorption of copper(II) from solutions on new spherical cellulose adsorbent

An investigation was conducted on the adsorption and desorption of copper(II) from aqueous solutions with a new spherical cellulose adsorbent containing the carboxyl anionic group. Various factors affecting the adsorption were optimized. The adsorption of Cu²⁺ ions on the adsorbent was found to be dependent on the initial time and pH, the concentration, and the temperature. The adsorption process follows both Freundlich and Langmuir adsorption isotherms and was found to be endothermic (ΔH = 23.99 kJ/mol). The Cu²⁺ ions adsorbed on the adsorbent can be recovered with a NaOH or HCl aqueous solution. The maximum percentage of recovery is about 100% when 2.4 mol/L HCl solution is used. In addition, only 7.2% of the adsorption capacity is lost after 30 replications of the adsorption and desorption. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 478–485, 2002; DOI 10.1002/app.10114     

含氮、硫蔗渣纤维素吸附剂的制备及其吸附性能

将蔗渣纤维素进行碱活化处理后与乙二胺四乙酸二钠在KMnO4/H2SO4引发下进行接枝共聚反应,然后在碱性条件下与CS2作用可得兼具氮、硫元素的纤维素吸附剂,该吸附剂对Cu(Ⅱ)、Cr(Ⅵ)、Pb(Ⅱ)、Zn(Ⅱ)等重金属离子有良好的吸附作用.