聚二甲基二烯丙基氯化铵/偶联剂改性膨润土对苯酚的吸附研究

采用阳离子聚电解质聚二甲基二烯丙基氯化铵(PDMDAAC)和硅烷偶联剂(KH550)对钙基膨润土进行改性,得到有机改性膨润土.研究发现,PDMDAAC和KH550成功负载在膨润土表面,其结构没有发生改变.以苯酚为吸附对象,采用该有机改性膨润土对其进行模拟吸附,当有机改性膨润土的投加量为2g/L,吸附时间20min,pH...     

Fe-Al柱撑膨润土对水溶液中铅离子的吸附性能研究

以羟基铁铝为柱化剂制备了Fe-Al柱撑膨润土,并研究了其对水溶液中铅离子的吸附去除性能.结果表明:Fe-Al柱撑膨润土对水溶液中的铅离子有很好的去除效果,当其用量为20 g/L时,水溶液中铅离子的吸附去除率达到88.4%;Fe-Al柱撑膨润土对水溶液中的铅离子的吸附在60 min时达到平衡;溶液pH值对水溶液中铅离子的去除有一定的影响,中性和弱碱性条件下的去除率大于酸性时.平衡吸附量与吸附平衡浓度之间的关系符合Freundlich和Langmuir等温吸附方程所描述的规律.     

用有机膨润土吸附处理含铬(Ⅵ)废水的研究

采用溴化十六烷基三甲铵(CTMAB)对天然膨润土进行了有机改性处理,并在静态条件下,进行了有机膨润土对含Cr(Ⅵ)工业废水的吸附试验.研究了CTMAB浓度、有机膨润土用量、废水pH值、搅拌时间等因素对Cr(Ⅵ)去除率的影响,确定了用有机膨润土处理含Cr(Ⅵ)废水的适宜条件.结果表明,有机膨润土能有效地除去废水中的Cr(Ⅵ),其最佳工艺条件为废水pH值3.0～5.0、搅拌时间约30 min、有机膨润土用量10 g/L,按该工艺条件对含Cr(Ⅵ)35 mg/L左右的废水进行处理,铬的去除率达到98.0%以上,处理后的水样中Cr(Ⅵ)含量小于0.50 mg/L,达到国家排放标准.     

壳聚糖插层有机膨润土的制备及吸附性能研究

采用微波辅助法,以十六烷基二甲基苄基溴化铵及壳聚糖对膨润土进行改性,制备了一种新型的壳聚糖插层有机膨润土材料。通过红外光谱(FTIR)、X-射线衍射(XRD)及扫描电镜(SEM)对膨润土及插层膨润土进行了表征。结果表明壳聚糖已经进入膨润土层间,层间距由1.41nm增大至2.04nm。对该材料吸附水中苯酚的性能进行了研究,结果显示在25℃,pH=6的条件下,最大理论吸附量为73.25mg/g,最大理论吸附量随温度升高而降低。用不同模型对等温线进行了拟合,结果表明等温吸附平衡更符合Langmuir模型。     

有机改性膨润土吸附污水中Cr~(6+)的研究

以十六烷基三甲基溴化铵为有机插层剂,研究钠基膨润土有机化的影响因素及有机膨润土吸附低浓度含Cr6+废水的热力学行为。结果表明,制备有机膨润土的优化工艺条件是:体系pH为7,活化温度为70℃,配料比为1.1 mmol/g,固液比为0.05 g/mL,活化时间为1 h;当有机膨润土的质量浓度为8 g/L时,对水溶液中Cr6+的去除率可达98%以上;有机膨润土吸附Cr6+符合Freundlich等温吸附方程。     

阳离子改性的有机复合膨润土吸附材料的制备、表征及吸附性能研究

用十六烷基三甲基氯化铵(1631)、十八烷基三甲基氯化铵(1831)阳离子表面活性剂分别与四乙烯五胺(TEPA)、二乙基二硫代氨基甲酸钠(DDTC)复合改性哈密膨润土,制得系列改性膨润土吸附材料。FT-IR、XRD和TGDTA等表征结果表明,改性及有机复合改性膨润土的层间距显著增大。以新疆新鑫冶炼厂实际废水为吸附研究对象,研究发现,当改性膨润土投加量为25g/L、pH为9.0、吸附时间为60min时,有机改性膨润土对冶炼废水中Cu~(2+)、Ni~(2+)的去除率可达78%左右,而有机复合改性膨润土对废水中Cu~(2+)、Ni~(2+)的去除率最高可达95%以上,若吸附条件控制得当,经有机复合改性膨润土处理后的冶炼废水,其Cu~(2+)、Ni~(2+)的含量可达到国家排放标准。     

PAAS高吸水树脂对重金属离子盐溶液的吸液及吸附性能

用聚丙烯酸高吸水树脂(PAAS)研究了单一和混合重金属离子硝酸盐溶液中的吸液和吸附性能.在Pb2 、Ni2 、Cd2 、Zn2 、Mn2 和Cu2 的一、二元溶液中,PAAS的吸液倍率随时间延长而增加,约50min达吸液平衡,一元金属离子溶液中平衡吸液倍率为160～190g/g,而对Cr3 溶液,最大为120g/g;二元金属离子混合溶液中平衡吸液倍率都在150～180g/g之间,有Cr3 存在时平衡吸液倍率最小.对上述单一金属离子的吸附量随时间延长而增加,约180min达吸附平衡,平衡吸附量顺序为:Pb2 ＞Cd2 ＞Ni2 ＞Cu2 ＞Zn2 ＞Mn2 ＞Cr3 .对二元混合金属离子溶液,吸附量随时间增加而增加,30min后逐渐变慢,约70min后达吸附平衡.     

银杏落叶对结晶紫的生物吸附性能研究

以银杏落叶作为生物吸附剂,采用静态吸附法处理结晶紫模拟废水溶液。结果表明:吸附时间、银杏落叶投加量、pH值、结晶紫初始浓度、盐浓度等因素对结晶紫吸附效果有一定影响,吸附平衡时间90min,银杏落叶投加量4g/L,中性条件下,对120mg/L结晶紫有较好的吸附效果。吸附符合Langmuir和Freundlich等温吸附模型,最大吸附量为188.68mg/g。吸附动力学符合准一级和准二级动力学模型,可用准二级动力学模型更好的描述,表明该吸附剂在染料废水处理中有较好的应用前景。     

超声波法对吸附Ni(Ⅱ)吸附剂的再生

目前,有关超声波对有机改性凹凸棒黏土吸附剂的再生研究不多。研究了有机改性凹凸棒黏土吸附剂吸附Ni(Ⅱ)后,在超声波作用下再生后吸附Ni(Ⅱ)的效果及其与再生各因素的关系,分析了超声波对吸附剂的再生机理。结果表明:用超声波法对有机改性凹凸棒黏土吸附剂进行再生,在超声波频率40 Hz、功率500 W的条件下,最佳再生温度为45℃,最佳再生时间为1 min,最佳再生pH值为6,最佳再生固液比为7 g/L。吸附剂再生5次后,仍有较好的吸附效果。     

改性膨润土对溶液中Co2+、Mn2+的吸附研究

以膨润土为原材料,盐酸为改性剂,制备改性膨润土。研究了改性膨润土的制备条件,其对重金属Co2+、Mn2+的吸附性能及对苯二甲酸(PTA)工业中的副产品对甲苯甲酸对吸附的影响。实验结果表明,盐酸的最佳改性浓度为1.5mol/L,改性膨润土在40℃的吸附能力最好,可达到12～14mg/g,经过热力学分析得出,改性膨润土对钴离子、锰离子的吸附方式均符合Langmuir吸附模型,PTA工业中的副产品对甲苯甲酸对吸附没有影响。     

改性膨润土对水溶液中草甘膦的吸附研究

分别用硫酸和十六烷基三甲基溴化胺（CTMAB）制备酸改性膨润土和有机改性膨润土,系统地研究了这两种改性膨润土对水溶液中草甘膦的吸附行为。结果表明：两种改性土都在碱性条件下吸附效果较好,草甘膦在酸改性膨润土上的吸附主要与表面羟基有关,在CTMAB改性膨润土上的吸附是分配机理起主要作用。草甘膦在酸改性膨润土上的吸附满足Langmuir吸附模型,吸附过程符合伪二级动力学方程,对CTMAB改性膨润土更满足Fkundlich吸附模型,吸附过程符合伪一级动力学方程。     

Mechanism of adsorption of anionic dye from aqueous solutions onto organobentonite

Organobentonite is suggested as potential super-sorbents for the removal of dyes from wastewater. All kinds of organobentonites are synthesized to adsorb dyes; however, the mechanism of the adsorption is still unclear. In this paper, organobentonites were first modified with hexadecyltrimethylammonium bromide at various amounts to reveal the adsorption mechanism. Subsequently, four kinds of organobentonites were utilized to adsorb acid dyes. Results show that the main mechanism of the adsorption of acid dye is an anionic exchange. The counter-ion bromide in the organobentonite was replaced by the dye anion. The study reveals that the adsorption capacity of organobentonite is affected by the surfactant alkyl chain length. When the longer alkyl chain surfactant was modified, bentonite showed higher adsorption capacity. Specific surface areas had no effect on the adsorption. However, the XRD patterns show that interlamellar distance and lamellar distribution have some effects on the adsorption. High adsorption capacity and low residual concentration were obtained by the organobentonite adsorbents. The revelation of the adsorption mechanism makes it possible to obtain more novel and suitable organobentonite adsorbents for anionic dye removal from wastewater.     

基于聚吡咯合成的多孔碳材料的CO2吸附性能

采用氢氧化钾做活化剂,聚吡咯做碳前驱体,高温化学活化法制备掺杂氮元素的多孔碳材料。在273K一个大气压下,二氧化碳吸附量可达182．36cm2g-1（8．14mmolg-1）,二氧化碳相对于氮气的选择性吸附系数为47：1,吸附量之比约为13：1。     

Adsorption of copper and lead in aqueous solution onto bentonite modified by 4'-methylbenzo-15-crown-5

The adsorption of heavy metal ions (Cu2+ and Pb2+) onto organobentonite modified by 4'-methylbenzo-15-crown-5 (MB15C5) from bentonite compared with natural bentonite (N-Bentonite) is described in this paper. The kinetic parameters of the models are calculated and discussed, and closely fitted a pseudo-second-order model in all cases. For bentonite modified with MB15C5 (MB15C5-Bentonite) and N-Bentonite, the equilibrium data closely fitted the Langmuir model and showed the following affinity order: Pb2+ > Cu2+, and the adsorption capacity of MB15C5-Bentonite is higher than that of N-Bentonite for Pb2+ and Cu2+. The effect of pH is examined over the range 1.5-6. The adsorption of Cu2+ and Pb2+ increases with increasing pH and the adsorption of Cu2+ and Pb2+ reaches a maximum at pH 3.5-6.     

Removal of phenol from aqueous solutions by adsorption onto organomodified Tirebolu bentonite: Equilibrium, kinetic and thermodynamic study

A natural bentonite modified with a cationic surfactant, cetyl trimethylammonium bromide (CTAB), was used as an adsorbent for removal of phenol from aqueous solutions. The natural and modified bentonites (organobentonite) were characterized with some instrumental techniques (FTIR, XRD and SEM). Adsorption studies were performed in a batch system, and the effects of various experimental parameters such as solution pH, contact time, initial phenol concentration, organobentonite concentration, and temperature, etc. were evaluated upon the phenol adsorption onto organobentonite. Maximum phenol removal was observed at pH 9.0. Equilibrium was attained after contact of 1 h only. The adsorption isotherms were described by Langmuir and Freundlich isotherm models, and both model fitted well. The monolayer adsorption capacity of organobentonite was found to be 333 mg g⁻¹. Desorption of phenol from the loaded adsorbent was achieved by using 20% acetone solution. The kinetic studies indicated that the adsorption process was best described by the pseudo-second-order kinetics (R² > 0.99). Thermodynamic parameters including the Gibbs free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were also calculated. These parameters indicated that adsorption of phenol onto organobentonite was feasible, spontaneous and exothermic in the temperature range of 0–40 °C.     

原位插层聚合制备PVC/膨润土复合材料及性能初步研究

以新疆夏子街钠基膨润土为原矿制备的有机膨润土,通过原位插层聚合法制备了PVC/膨润土复合材料.通过对该复合材料的力学性能分析,复合材料的断裂伸长率为42%,比原PVC基体提高51.5%;复合材料的抗冲击强度为15.58 kJ/m2,比原PVC基体提高2.1倍;复合材料的拉伸强度为42.82 MPa,比原PVC基体提高14.6%.由此表明,复合材料的综合性能明显提高.SEM分析表明,PVC/膨润土复合材料具有明显的韧性特征;XRD分析表明,该复合材料是一种剥离型的复合材料.     

微波强化掺Al-TiO_2改性膨润土的制备及其结构表征

为制备一种新型水处理吸附剂复合材料,在微波作用下,采用掺Al-TiO2作为改性剂制备改性膨润土,考察了最佳微波辐射条件,利用EDS、SEM、FTIR、XRD、N2吸附-脱附和差热热重(DSC-TGA)等手段对样品进行表征。结果表明:辐射功率260 W,辐射时间8min为最佳微波辐射条件;改性膨润土中的改性剂已进入到膨润土层间,与蒙脱石骨架发生成键反应,形成Ti—O—Si键;改性膨润土的层间距由1.280nm增大至1.533nm,比表面积由39.66m2·g-1增大至72.05m2·g-1,孔隙体积由0.103 4cm3·g-1增大至0.140 5cm3·g-1,对亚甲基蓝的饱和吸附量也由32.56g/100g增大至57.96g/100g,且热稳定性较改性前明显提高。     

Adsorption thermodynamics of stearic acid onto bentonite

Adsorption equilibrium of stearic acid onto natural bentonite with Turkish origin was studied at the temperatures of 298, 308 and 318 K. SEM and XRD analysis show that the bentonite used as adsorbent is composed of microcrystal and porous structure. The specific surface area was determined by BET method as 38.6 m(2)/g. The adsorption of stearic acid onto bentonite was conformed to the Langmiur and Freundlich isotherms. The equilibrium parameter, R(L) revealed that the bentonite is a good adsorbent for stearic acid. The sorption capacity of bentonite studied decreases with increasing temperature. However, it is concluded that the adsorption capacity of bentonite for the stearic acid under the same experimental conditions is in comparable level in terms of that of the rice husk ash given in literature. Thermodynamic parameters, DeltaG(ads) degrees , was calculated to be between -21.8 and -22.8 kJ mol(-1). DeltaH(ads) degrees and DeltaS(ads) degrees were found to be -9.2 kJ mol(-1) and 42.4 J mol(-1)K(-1), respectively. These parameters obtained as a function of temperature indicate that the adsorption of stearic acid onto bentonite was a spontaneous and an exothermic process. An FT-IR study on the adsorbed material was used to verify the interaction of the stearic molecule with bentonite after adsorption process.     

羟基铁插层膨润土的制备及其对铀(VI)的吸附特性与机制

通过羟基铁对钠基膨润土插层改性制备了羟基铁插层膨润土（OH-Fe-Bent）,用于去除废水中的U（VI）。实验考察了pH值、U（VI）初始浓度、温度和吸附时间对OH-Fe-Bent吸附U（VI）效果的影响,并进行吸附动力学和热力学分析。采用FTIR、SEM、XRD等手段分析相关吸附机制。实验结果表明:OH-Fe-Bent吸附U（VI）的最佳pH为4,在温度为15℃,投加量为0.8 g/L,U（VI）初始浓度为10 mg/L时,OH-Fe-Bent对U（VI）的去除率达到99.55%,吸附平衡时间为90 min。Langmuir等温吸附模型和准二级动力学模型（相关系数的平方约为1）均可较好地拟合其吸附过程,理论饱和吸附量可达97.09 mg/g,OH-Fe-Bent对U（VI）是单分子层吸附。FTIR、SEM分析表明OH-Fe-Bent吸附U（VI）后自身结构没有改变,XRD分析表明羟基铁已经成功插入膨润土层间。      

Adsorption of basic dyes from single and binary component systems onto bentonite: simultaneous analysis of Basic Red 46 and Basic Yellow 28 by first order derivative spectrophotometric analysis method

The present study deals with the simultaneous analysis and adsorption of Basic Yellow 28 and Basic Red 46 dyes in binary mixture onto bentonite. First order derivative spectrophotometric method was used for simultaneous analysis of BY28 and BR46 in binary mixtures. The adsorption experiments were carried out in a batch system. The mono- and multi-component Langmuir and Freundlich isotherm models were applied to experimental data and the isotherm constants were calculated for BY28 and BR46 dyes. The monolayer coverage capacities of bentonite for BY28 and BR46 dyes in single solution system were found as 256.4 mg/g and 333.3mg/g, respectively. It was observed that the equilibrium uptake amounts of BY28 and BR46 dyes in binary mixture onto bentonite decreased considerably with increasing concentrations of the other dye resulting in their antagonistic effect. The adsorption equilibrium data fitted more adequately to mono-component Langmuir isotherm model than mono-component Freundlich isotherm model, while the extended Freundlich isotherm model adequately predicted the multi-component adsorption equilibrium data at moderate ranges of concentration. Thermodynamic parameters showed that adsorption of BR46 and BY28 was endothermic and spontaneous in nature.