改性膨润土及其在水处理中的应用

本文简要概述了膨润土的基本组成、结构及性质,并重点讨论了膨润土的改性方法,包括焙烧、酸化、和化学改性。综述了改性膨润土在水处理的应用。最后提出了改性膨润土在水处理中存在的问题和发展方向。     

膨润土的改性及在废水处理中的应用研究进展

介绍了膨润土的结构与基本性质,探讨了近年来对膨润土的活化、有机改性、无机改性,及无机/有机复合改性方法,以及改性膨润土在含重金属离子废水、有机废水及含磷废水中的应用研究进展,并指出目前膨润土在环境应用中存在的问题及应用前景.     

膨润土改性的研究进展

介绍了膨润土的结构与基本性质,重点介绍了膨润土的活化、有机改性、无机改性,及无机/有机复合改性方法,并指出目前膨润土在环境应用中存在的问题及应用前景.     

改性膨润土对废水中染料的吸附

简述了膨润土的基本结构,概括了膨润土的主要改性方法,即活化改性法和添加改性剂改性法;分析了改性方法的主要优点,总结了改性膨润土对废水中染料的吸附效果.结果表明,改性膨润土对染料的吸附效果较好,染料去除率最大可达99.7％.另外,探讨了改性膨润土的吸附机理、影响因素和吸附等温式,并展望了改性膨润土的应用前景.     

膨润土改性方法的研究进展

概述了膨润土的基本组成、结构及性质,并着重介绍了膨润土的几种改性方法及原理。     

膨润土在废水处理中的应用

概述了膨润土的基本组成、结构及性质,尤其对膨润土及改性膨润土在废水处理中的应用作了较为详细介绍,并对其前景进行展望。     

改性膨润土及其在废水处理中的应用

对膨润土的结构及其基本性质做了简单介绍,重点探讨了改性膨润土及其在去除重金属离子、去除有机污染物、除磷及脱色等废水处理领域中的应用,并指出了目前改性膨润土在废水处理中存在的问题。     

膨润土有机改性提高分散性的研究进展

介绍了国内对膨润土进行有机改性提高分散性的主要研究进展,包括季铵盐改性膨润土、氯铵盐改性膨润土、溴铵盐改性膨润土、酰胺改性膨润土、吡啶改性膨润土、硅烷改性膨润土、十二烷基磺酸钠改性膨润土等,对这些方法做了比较及评价,并对今后的研究方向提出建议。     

膨润土有机改性提高分散性的研究进展

介绍了国内对膨润土进行有机改性提高分散性的主要研究进展,包括季铵盐改性膨润土、氯铵盐改性膨润土、溴铵盐改性膨润土、酰胺改性膨润土、吡啶改性膨润土、硅烷改性膨润土、十二烷基磺酸钠改性膨润土等,对这些方法做了比较及评价,并对今后的研究方向提出建议。     

改性膨润土对废水中Cd(II)的吸附特征及吸附动力学研究

为探讨改性膨润土对Cd(II)的吸附特征及吸附动力学机制,通过吸附实验探讨了pH值、初始浓度和吸附时间对改性膨润土吸附Cd(II)的影响。结果表明,盐酸改性膨润土对Cd(II)的去除率表现为随溶液pH值升高而升高,而氢氧化钠改性膨润土、膨润土与十二烷基磺酸钠改性膨润土的去除率分别在pH=6和7时达到最大值。膨润土及改性膨润土对Cd(II)的去除率随初始浓度的增加而降低,吸附量随平衡浓度增加而增大,并趋向平稳,吸附符合Langmuir方程,吸附为单分子层吸附。膨润土及改性膨润土的吸附反应在240 min内基本达到平衡,吸附动力学分析表明吸附过程更符合准二级动力学模型,吸附过程以化学吸附为主,膨润土及改性膨润土的吸附速率大小依次为K2HCl-B＞K2NaOH-B＞K2B＞K2SDS-B,液膜扩散与颗粒内扩散过程均为控速步骤。该研究可为改性膨润土处理含镉废水和修复镉污染土壤提供参考。     

Influences of solution and mixed soil on estimating bentonite content in slurry using electrical conductivity

Successful construction of soil–bentonite barrier system requires monitoring of the bentonite content during construction to ensure that the quantity of bentonite is adequate and the distribution of bentonite is uniform. In this study, factors affecting the electrical properties of bentonite slurry were identified and electric conduction mechanisms which prevail in bentonite slurry were examined. The electrical conductivity of both bentonite and soil–bentonite slurries linearly increased with bentonite content due to the dissolution of cations from bentonite particles. The linear relationship between electrical conductivity and bentonite content was affected by the solution electrical conductivity and fine content in soil–bentonite mixture. As the initial solution electrical conductivity increased, the slope of the regression lines decreased. In addition, the y-intercept was found to increase slightly with an increase in fine content. The empirical relationship between electrical conductivity and bentonite content considering the combined influence of fine content and slurry solution was derived. Based on the suggested relationships, the bentonite content in bentonite and soil–bentonite slurry can be quantitatively evaluated by using an electrical conductivity measurement method.     

膨润土改性产品在废水处理中的应用及进展

本文介绍了膨润土基本的矿物学性质,阐述了膨润土及其改性产品在废水处理中的有效作用及应用前景。膨润土经改性后可用于处理多种工业废水,其中对染料废水、重金属离子废水和有机废水,其去除率比原土高。同时,对膨润土的发展应用问题进行了展望。     

膨润土在工业废水处理中的应用研究进展

介绍了膨润土基本性质,阐述了膨润土及改性膨润土对工业废水中有机物和无机物处理等方面的应用现状,对比了膨润土改性前后对工业废水中所含致污物质的处理效果,表明了改性膨润土在处理工业废水上的有效作用:膨润土经活化或改性后可用于处理有色染料废水,有机膨润土对水中有机物和重金属离子的效果的去除率比原土高,但膨润土处理较高含量的无机非金属废水效果不理想.对膨润土的应用前景及回收利用问题进行了展望,认为如将使用过的膨润土直接用作建筑材料,如用于制砖和铺路以及回填至垃圾填埋场,可能更具有实用价值.     

膨润土在废水处理中的应用研究进展

介绍了膨润土的结构、性能及改性膨润土在废水处理中的应用．尤其对改性膨润土在含重金属离子、有机污染物、有色污染物等方面的治理应用作了较为详细的介绍。同时指出改性膨润土在应用中存在的问题．展望了其应用前景。     

膨润土改性及其应用研究

为了改善膨润土的性能,扩大其使用范围,综述了膨润土的结构和针对这种独特的片层结构进行的改性原理及方法,以及制备得到钠化改性膨润土、活化膨润土、有机改性膨润土和纳米复合膨润土等不同类型的改性膨润土,并分析了膨润土改性后在环境保护、载体等领域的应用与前景。改性膨润土大大提高了膨润土的性能与品质,改变了中国膨润土资源品质低、应用受到限制的局面,有助于充分利用好中国丰富的膨润土资源,提高其附加价值,创造更大的经济效益。     

有机膨润土的制备

简要介绍了膨润土和有机膨润土特性与应用，介绍了以天然在膨润土为原料经过提纯，改性处理，制得有机膨润土的过程。     

膨润土在环境污染治理方面的研究进展

综述了国内外有关膨润土在环境污染治理方面的研究进展，膨润土及其改性产物（活化膨润土，有机膨胀润土，交联膨润土，有机交联膨润土）由于具有良好的吸附性能，在环境污染治理方面得到了越来越广泛的应用。在对含有机污染物，重金属的废水处理中，膨润土是一种高效吸附剂，欧美国家在土壤和地下水污染的防止和修复方面取得了较大的进展，近年来，有关膨润土用于放射性废物处置的理论研究活跃。     

A study of the mineralogical alteration of bentonite in saline water

The mineralogical alteration of bentonite was studied in saline water at 60 and 90 °C. To obtain the altered bentonite, a crude bentonite (Kunigel V1) was dispersed into simulated sea-water, and maintained at 60 or 90 °C over 6000 h. Magnesium was accumulated into bentonite during the experiments at levels over the cation exchange capacity (CEC; 0.78 meq/g for the original bentonite) at only 90 °C. The excess Mg was not replaced by ammonium ions, suggesting that the precipitation of Mg solid in bentonite occurred. The IR spectra and the thermogravimetric/differential Thermal Analysis (TG-DTA) profiles show the neo-formation of magnesium hydroxide in the altered bentonite. The CEC decreased from 0.78 to 0.45 meq/g as the amount of accumulated Mg increased. The distribution coefficient K_d for Cs in the altered bentonite was half of that in the original bentonite. It is conjectured that the thermal alteration of bentonite in saline water affects the sorption capacity of Cs onto smectite.     

Adsorption of Bezanyl Red and Nylomine Green from aqueous solutions by natural and acid-activated bentonite

The adsorption of two acid dyes, namely, Red Bezanyl and Green Nylomine, onto natural bentonite and acid activated bentonite from aqueous solutions were studied in a batch system. The kinetic data show that at the equilibrium, the acid-activated bentonite fixes more Bezanyl Red and Nylomine Green than the natural bentonite. Adsorption equilibrium was reached within 2 h. The results also showed that the kinetics of adsorption is best descibed by a pseudo second-order expression than a first or second-order model. Adsorption isotherms of acid dyes onto bentonite and acid-activated bentonite were determined and correlated with common isotherm equations such as the Langmuir and Freundlich models. The Langmuir model agrees very well with the experimental data. For better explanation of these results, the natural bentonite and acid-activated bentonite have been examined in detail through FTIR, BET and XRD analyses.