改性膨润土吸附剂的制备及应用研究

以AlCl3为改性剂研究了制备改性膨润土水处理吸附剂的条件，探讨了影响改性膨润土吸附去除苯酚效果的因素。结果表明：当AlCl3投量为25g／100g原土、焙烧温度为450℃时，所制得改性膨润土吸附剂的比表面积和微孔总体积分别为350．21m^2／g和0．907cm^3／g。采用该吸附剂处理苯酚废水（苯酚浓度为200mg／L）的试验结果表明，在改性膨润土吸附剂投量为4g／L、溶液的pH值为8．5、反应时间为30min的条件下，对苯酚的去除率达到了92．2％；对数据的回归分析显示，改性膨润土对苯酚的吸附符合Freundish方程。     

La(OH)_3改性膨润土制备及其对磷吸附性能研究

采用硝酸镧和氢氧化钠制备La(OH)_3改性膨润土,利用扫描电子显微镜(SEM)、能量色散X射线荧光光谱仪(EDX)和X射线衍射分析仪(XRD)对改性前后样品的组成、形貌进行表征,并分析了初始pH值、吸附剂添加量和吸附时间对其吸附磷性能的影响。结果表明,改性后膨润土形貌和成分均有明显变化;增加改性膨润土用量和吸附时间在一定范围内有助于提高对磷的吸附量,其吸附动力学可用拟二级动力学方程描述,等温吸附模型符合Langmuir方程。     

活性MgO、La(OH)_3的表征及去除水中F~-的吸附性能研究

实验采用活性MgO和La(OH)3为吸附剂,对其去除水中氟离子的性能进行了研究.采用BET、XRD、TEM、SEM、FTIR等现代化手段对活性MgO和La(OH)3进行表征.探讨了pH、吸附时间、初始浓度、吸附剂投加量以及共存离子等因素对这两种吸附剂吸附性能的影响.影响因素的研究表明,活性MgO吸附剂最适宜的吸附条件为pH=6~7,温度20~25℃,吸附剂投加量约为1g/L;La(OH)3的最适宜条件为pH=4,温度20~25℃,吸附剂投加量约为1g/L.活性MgO的吸附容量约为55mg/g,La(OH)3的吸附容量约为7.2mg/g.     

重金属Pb(II)在膨润土上去除特性研究

深入研究成本低廉的膨润土对水溶液中Pb(II)的吸附特性,采用Batch试验方法,分析了土水比、pH、离子强度、反应时间、温度及Pb(II)的初始浓度对Pb(II)在膨润土上吸附性能的影响,并对吸附动力学和吸附平衡试验进行了探讨。Pb(II)在膨润土上去除率与pH、离子强度有很强的依赖性。当pH<7时,膨润土对Pb(II)的吸附主要是离子交换,而当7相似文献   

基于膨润土制备的水泥基多孔材料吸附性能研究

以膨润土作为矿物掺合料,42.5R水泥、发泡剂、减水剂为主要原材料,制备水泥基多孔材料。探究了发泡体系、膨润土种类、膨润土掺量及吸附时间对水泥基多孔材料吸附性能的影响。结果表明：动物蛋白发泡剂发泡制备的多孔材料对Cu²⁺吸附率高于双氧水发泡剂;有机膨润土及钠基膨润土掺量分别为50%、30%时水泥基多孔材料对Cu²⁺吸附率最高。由动物蛋白发泡内掺有机膨润土制备的水泥基多孔材料饱和吸附时间为130 min。     

改性膨润土吸附剂的制备及其吸附性能的研究

本文以钠基膨润土为主要原料,选用壳聚糖作为改性剂,通过微波辐射进行改性,制备出壳聚糖改性膨润土吸附剂,并研究了其对Cr（VI）的吸附陛能和吸附工艺条件。结果表明,吸附剂对Cr（VI）具有较好的吸附性能,吸附的适宜工艺条件是：pH值为5-6,吸附时间为30min,吸附剂用量为12．0g／L。与单一的膨润土或壳聚糖相比,该吸附剂对Cr（VI）离子的吸附速度快、吸附能力强,并且具有成本低、应用范围广的优点,Cr（VI）的去除率可达N85％。     

污泥吸附剂的制备及其对亚甲基蓝的去除研究

以城市污水厂脱水污泥、锯末和焦油的混合物为原料,选择ZnCl2为活化剂制备出过渡孔发达、强度大的优质污泥吸附剂(S-AC),借助BET、FTIR、DT等现代分析测试方法对污泥吸附剂进行表征,并通过吸附动力学、吸附等温线来研究污泥吸附剂的吸附性能;同时,将吸附剂应用于亚甲基蓝溶液的处理,并选择商品活性炭(AC)进行对照试验。结果表明,制得的污泥吸附剂的BET比表面积为358.0 m2/g;在试验浓度范围内,污泥吸附剂在温度分别为20、30和40℃时对亚甲基蓝的最大吸附量分别为57.13、59.37和61.79 mg/g,试验数据均符合Freundlich吸附等温方程;吸附剂的动力学数据均符合液膜扩散方程,液膜扩散为吸附过程的主控步骤。     

Pb^2＋在天然膨润土中的吸附热力学特征研究

通过静态吸附实验探讨了天然膨润土吸附水中Pb^2＋时的热力学特性,结果表明：平衡吸附量随着温度的上升而上升;不同温度下的吸附等温式都基本遵从Freundlich方程,表明吸附为单分子层的吸附,吸附剂表面不均匀。热力学分析表明,吸附过程吸热且反应能自发进行。     

膨润土、累托石和沸石对Sr^2＋的吸附性能研究

本文在研究膨润土、累托石和沸石样品的矿物组成和基本物化性能的基础上,以这三种样品作为吸附剂,研究它们在静态条件下对Sr2＋的吸附效果。结果表明：在静态吸附条件下,三种样品的吸附效果因物化性质的不同而有所差异,其中,膨润土的吸附效果要好于其他两种样品。三种样品对Sr2＋的吸附率都随着原液浓度的增加而减小,随着吸附剂量的增加而增大。0.1g的膨润土、累托石和沸石样品的最大吸附量分别为19.71mg/g,11.83mg/g,12.27mg/g,对应于0.0 mol/L,0.005mol/L,0.01mol/L的原液浓度获得。     

膨润土对重金属离子Pb~(2+),Zn~(2+),Cr(VI),Cd~(2+)的吸附性能

试验研究了pH值、吸附时间和吸附剂用量对膨润土吸附重金属离子Pb2 ,Zn2 ,Cr(VI)和Cd2 的影响.结果表明,在本试验的pH值、吸附时间及吸附剂用量条件下,膨润土对Pb2 ,Zn2 ,Cd2 的吸附效果均优于其对Cr(VI)的吸附效果;pH值是影响上述吸附的重要因素,离子交换和表面络合是上述吸附的主要形式.     

Removal of Pb(ii) from aqueous/acidic solutions by using bentonite as an adsorbent

The ability of bentonite clay to remove Pb(II) from aqueous solutions and from nitric acid, hydrochloric acid and perchloric acid solutions (1.0-1 x 10(-5)) has been studied at different optimized conditions of concentrations, amount of adsorbent, temperature, concentration of electrolyte and pH. Maximum adsorption of Pb(II), i.e. > 98% has been achieved in aqueous solutions, while 86% is achieved from 1.0 x 10(-5) M HCl using 0.5 g of bentonite. The adsorption decreases by increasing the concentration of electrolytes. Flame atomic absorption spectrometer was used for measuring lead concentration. Isotherm analysis of adsorption data obtained at 25 degrees C, 30 degrees C, 40 degrees C and 50 degrees C showed that the adsorption pattern of lead on bentonite followed the langmuir isotherm and freundlich isotherm, respectively. DeltaH(o) and deltaS(o) were calculated from the slope and intercept of ln K(D) vs. I/T plots.     

Adsorption of Cu(II) from industrial liquid waste on Na-bentonite and Al-PILC following a full factorial design

The paper reports a study of the performance of Maghnia bentonite in a purified and modified state for the removal of Cu(II) from industrial liquid waste in the region of Oran (North West Algeria). Bentonite was firstly treated to produce a Na-bentonite, then modified with an aluminum solution containing molar ratio OH/Al of 1.8 and finally calcined at 450 °C. The polymer [AlO₄Al₁₂(OH)₂₄(H₂O)₁₂]⁷⁺ formed in solution was adsorbed by surface complexation on the bentonite, which is known to have a high capacity to fix metal cations. The prepared materials were characterized by DRX, BET and EDX. In order to find the optimum conditions, a full factorial design of 2⁴ allowed us to determine the main effects and interactions of the factors studied: pH, mass of materials, contact time and temperature. The results obtained show that the best rate of adsorption of copper requires a pH = 10, a mass = 0.8 g, a stirring time = 80 min, and a temperature = 25 °C. The adsorption capacity of treated bentonite increased considerably from 4.147 mg/g for Na-bentonite to 7.173 mg/g for pillared aluminum bentonite. This shows the strong adsorption of copper compared with Na-bentonite, caused by its high surface area.     

Efficient removal of methyl orange from aqueous solution using amidoxime adsorbent

The amidoxime adsorbent was prepared by radiation grafting of acrylonitrile on non-woven polyethylene followed by chemical treatment with hydroxyl amine hydrochloride. The prepared amidoxime adsorbent was used for adsorption of methyl orange (MO) from aqueous solution. The effect of different conditions such as contact time, pH and initial metal ion concentration on the adsorption capacity was investigated. Pseudo-first-order and pseudo-second-order equations were used to study the kinetic adsorption data. A Langmuir isotherm model was used to investigate the equilibrium experimental data. The monolayer saturation adsorption capacity of the adsorbent for MO, as determined from the Langmuir equation, was 142 mg/g of the adsorbent. Moreover, desorption and reuse of the adsorbent film showed satisfactory results. Large-scale recycling of the adsorbent will reduce the production cost, and thereby make the practical application of the adsorbent economically feasible.

Abbreviations: Acrylonitrile - AN, Polyethylene - PE, Methylene Orange - MO     

膨润土的改性研究及在污水治理中的应用

介绍了蒙脱石的结构和基本性质 ,对近年来我国膨润土的活化、改性技术如焙烧活化、酸活化、无机改性、有机改性、交联膨润土的合成和改性机理及改性效果进行了归纳总结。活化改性改善了蒙脱石的微观结构 ,提高了膨润土的吸附能力和离子交换能力 ;对改性膨润土在污水治理中的应用进行了综述。改性膨润土可去除水体中的重金属离子、芳香族化合物、有毒难生物降解有机物 ,还具有脱色、脱磷、除臭等作用。给出了改性膨润土去除水中重金属离子、有机污染物的机理。指出了膨润土在污水处理中存在的问题 ,并展望其应用前景 ,认为膨润土是一种很有前途的污水处理材料。     

无机—有机复合膨润土用于焦化废水的深度处理

对辽宁省黑山钙基膨润土进行有机—无机复合改性,开发了一种高效、廉价的吸附剂,并将其用于焦化废水的深度处理,考察了膨润土粒径、反应温度、吸附剂投量、反应时间、pH等因素的影响。结果表明,经5g/L的Al2（SO4）3及0．02mol／L的十六烷基三甲基溴化铵（CTMAB）复合改性的膨润土,能同时去除焦化废水二级生化出水中残留的氨氮和COD,在投量为40g/L、反应时间为30min、反应温度为25℃、pH值为9的条件下,对氨氮和COD的去除率可分别达75％和47％,处理出水的氨氮和COD可分别降至25mg／L和150mg／L以下,为焦化废水的再生回用创造了条件。     

Removal of mercury(II) from aqueous solutions and chlor-alkali industry wastewater using 2-mercaptobenzimidazole-clay

The 2-mercaptobenzimidazole loaded natural clay was prepared for the removal of Hg(II) from aqueous media. Adsorption of the metal ions from aqueous solution as a function of solution concentration, agitation time, pH, temperature, ionic strength, particle size of the adsorbent and adsorbent dose was studied. The adsorption process follows a pseudo-second-order kinetics. The rate constants as a function of initial concentration and temperature were given. The adsorption of Hg(II) increased with increasing pH and reached a plateau value in the pH range 4.0-8.0. The removal of Hg(II) was found to be >99% at an initial concentration of 50 mg/l. Mercury(II) uptake was found to increase with ionic strength and temperature. Further, the adsorption of Hg(II) increased with increasing adsorbent dose and decrease with adsorbent particle size. Sorption data analysis was carried out using Langmuir and modified Langmuir isotherms for the uptake of metal ion in an initial concentration range of 50-1,000 mg/l. The significance of the two linear relationships obtained by plotting the data according to the conventional Langmuir equation is discussed in terms of the binding energies of the two population sites involved which have a widely differing affinity for Hg(II) ions. Thermodynamic parameters such as changes of free energy, enthalpy, and entropy were calculated to predict the nature of adsorption. It was found that the values of isosteric heat of adsorption were varied with surface loading. The chlor-alkali industry wastewater samples were treated by MBI-clay to demonstrate its efficiency in removing Hg(II) from wastewater.     

Removal of Ga(III) from aqueous solution by adsorption on activated bentonite using a factorial design

The purpose of the work is to study the adsorption of gallium(III) on bentonite from aqueous solutions. The important parameters, which affect the adsorption, such as pH of solution, mass of bentonite and temperature have been investigated. The results of parameters study showed that when pH and mass of bentonite increase there was a significant increase of Ga(III) at 20 degrees C and the optimum conditions were as follows: pH of solution (2.50), mass of bentonite (3.50 g) and temperature (20 degrees C). An experimental test carried out using a factorial design 2(3) indicated that pH and mass of bentonite have a positive effect, whereas temperature has negative effect. The interaction effect between pH and mass of bentonite was an important significant factor for gallium adsorption.     

温度对GMZ膨润土的膨胀性能影响研究

在25℃,40℃,60℃和90℃的蒸馏水中对高庙子(GMZ)膨润土进行了膨胀性能试验。由于在试验条件下渗透膨胀占主导地位,GMZ膨润土的膨胀性能随温度的升高而增大,其中最大膨胀率随温度线性增加,而膨胀力随温度呈指数增加。压实GMZ膨润土的膨胀性能可用em=Kp^D-3表示。N2吸附试验结果表明温度对GMZ膨润土的表面分维D基本没有影响。在渗透膨胀条件下,采用扩散双层模型计算发现膨胀系数K与温度T_c之间存在线性关系,并且通过GMZ膨润土和Bikaner膨润土的膨胀试验进行了验证。将K–T_c线性关系与e_m–p分形关系相结合,提出了温度作用下GMZ膨润土膨胀性能的一种简便定量评价方法。