胺基化超高交联吸附树脂对苯酚和苯胺吸附行为的研究

在超高交联吸附树脂上负载不同胺基后,无论是在非水体系还是在水体系中,树脂对苯酚的吸附选择性大大增强.非水体系中,树脂对苯胺和苯酚的吸附是靠氢键作用,水体系中,树脂对苯酚的吸附是表面吸附和基团吸附综合作用的结果.动态吸附表明,树脂胺基化前(Rf18)树脂与季铵化后(Rs6 ) ,对苯胺和苯酚混合水溶液的动态吸附泄漏曲线差别较大.对Rf18树脂,苯酚首先在14 7BV(床体积)处泄漏,其泄漏液浓度上升很快,在2 12BV处达吸附饱和,苯胺在184BV处才开始泄漏,且其泄漏液浓度上升缓慢;在14 7～184BV之间可收集到苯酚溶液.对Rs6树脂,苯胺先泄漏(17BV处) ,其泄漏浓度很快趋于水平,在4 7BV处达吸附饱和;苯酚在4 4BV处开始泄漏,其泄漏曲线也上升很快,在79BV处趋于水平,在17～4 4BV之间可收集到苯胺水溶液.     

酚羟基修饰的超高交联聚苯乙烯树脂对苯酚吸附及脱附性能的研究

对超高交联聚苯乙烯树脂进行酚羟基修饰得到修饰后的超高交联聚苯乙烯树脂(JN-2),将该树脂与大孔吸附树脂(Amberlite XAD-4)和超高交联树脂(NDA-150)在水溶液中对苯酚进行吸附-脱附性能比较,经过酚羟基修饰的超高交联聚苯乙烯树脂(JN-2)对苯酚的吸附性能有所提高,同时脱附性能明显改善,该树脂可望在含酚废水治理中得到广泛应用.     

富羧类吸附树脂对水溶液中HIPI的吸附研究

以NDA99和NDA150树脂作为参照,通过等温吸附实验和吸附动力学实验探讨了修饰后的树脂对水溶液中5-对羟基苯基海因(HIPI)的吸附性能和机理.结果表明:羧基修饰的超高交联吸附树脂(FZH124)比NDA99和NDA150树脂对水溶液中HIPI具有更好的吸附效果,而且在303K时吸附效果最好.Langmuir和Freundlich方程均能较好拟合修饰树脂对HIPI的吸附等温线.HIPI在FZH124树脂上的动态吸附符合准一级动力学方程,303K时,树脂对HIPI的吸附速率最大,颗粒内扩散过程是该吸附过程的主要控制步骤.     

氨基修饰超高交联树脂对没食子酸的吸附性能

以亲水性小分子有机酸没食子酸作为研究对象,研究了氨基修饰超高交联树脂对没食子酸的吸附行为和机理.结果表明,氨基修饰超高交联树脂WJN-10对没食子酸有较高的吸附容量和吸附作用力;π-π共轭作用是树脂WJN-10吸附没食子酸主要作用力;WJN-10吸附没食子酸是物理吸附主导;吸附速率主要受控于颗粒内扩散过程;WJN-10对没食子酸有较好的吸附-脱附性能.     

胺基修饰的高度交联聚苯乙烯树脂对间苯二酚吸附行为研究

研究了AH系列胺基修饰的超高交联树脂对水溶液中间苯二酚的静态吸附行为特征,结果表明,它们对间苯二酚的吸附容量明显高于母体交联树脂NDA-100和大孔弱碱性阴离子交换树脂D301.AH系列树脂与吸附质分子之间不仅有范德华作用力,还存在着氢键等作用力.该类树脂对间苯二酚的吸附为自发的放热过程,属于以物理作用为主兼有弱化学作用的吸附过程.吸附速率符合准一级动力学方程,表观吸附速率常数随树脂胺基含量的升高而降低.     

超高交联树脂对苯胺和对硝基苯胺的吸附行为

吸附热力学;化学吸附;超高交联树脂对苯胺和对硝基苯胺的吸附行为     

盐对超高交联树脂吸附苯酚的机理影响研究

以超高交联吸附树脂NDA-101吸附苯酚为例,研究了水溶液中无机盐 (NaCl) 对吸附的影响规律,探讨了可能的吸附机理,并通过吸附等温线分析及吸附热力学结果给出了合理的解释.同时采用恒定波振荡理论和吸附等温方程联合模型可以很好的拟合相关穿透曲线.     

间氨基水杨酸修饰超高交联吸附树脂对酚类化合物的吸附行为

合成间氨基水杨酸修饰的超高交联吸附树脂LZ-01,比较LZ-01树脂与NJ-8树脂对对甲基苯酚和对硝基苯酚的吸附能力,研究LZ-01树脂在不同温度(288K,313K,318K)下吸附水溶液中对甲基苯酚和对硝基苯酚的静态吸附热力学和动力学行为。结果表明,由于LZ-01树脂具有更大的比表面积、更多的微孔且含有氨基、羟基和羧基等基团,使其对对甲基苯酚和对硝基苯酚的吸附量明显高于NJ-8树脂。Freundlich方程对等温吸附数据能够很好地拟合,吸附焓变绝对值小于40kJ/mol,表明吸附是焓驱动的物理吸附过程。LZ-01树脂对对甲基苯酚和对硝基苯酚吸附动力学均符合准一级动力学方程,吸附速率随温度升高而增大,颗粒内扩散是该吸附过程的速控步骤。     

氨基修饰超高交联树脂对单宁酸的吸附行为及机理研究

选用单宁酸作为天然有机酸中典型中分子、高水溶性有机酸,系统研究了氨基修饰超高交联树脂对单宁酸的吸附行为和机理.吸附等温线表明氨基修饰超高交联树脂WJN-08对单宁酸有较高的吸附容量,其静态饱和吸附量比传统商业吸附剂高15%以上;吸附表面分析表明离子键、π-π共轭作用和阳离子-π键是重要吸附作用力;吸附热力学试验表明树脂WJN-08吸附单宁酸是化学吸附主导,吸附焓变在20~22 kJ mol-1;吸附动力学试验表明树脂WJN-08吸附单宁酸速率同时受控于颗粒内扩散和膜扩散过程.动态小柱吸附-脱附实验表明树脂WJN-08对单宁酸有较好的吸附-脱附性能,饱和吸附量和穿透吸附量分别为24.43 mg g-1和19.56 mg g-1,脱附率为98.6%。     

超高交联树脂对壬基酚聚氧乙烯醚的吸附机理(英文)

研究了壬基酚聚氧乙烯醚(NPEO-10)在3种具有不同比表面积和孔径大小的超高交联树脂上的吸附行为与机理.3种超高交联树脂对壬基酚聚氧乙烯醚的吸附量受它们的比表面积和孔径大小以及溶液温度的影响.壬基酚聚氧乙烯醚在3种超高交联树脂上的吸附等温线可以用Langmuir和双Langmuir模型很好地拟合,而用Freundlich模型拟合则效果不好,但这些拟合曲线都具有相似的形状.热力学分析表明吸附过程主要表现为吸附质分子的疏水部分和吸附剂表面的作用以及吸附质分子在其表面形成胶束状的聚集体,即分散的、单层及双层聚集体的混合分布.吸附动力学曲线中的两个平台也证明了吸附过程存在单层和双层聚集体.脱附研究为实现超高交联树脂吸附分离水溶液中的壬基酚聚氧乙烯醚提供了合适的操作条件.     

BINARY COMPETITIVE AND COOPERATIVE ADSORPTION OF AROMATIC COMPOUNDS ON POLYMERIC RESINS

The adsorption behaviors of 2-naphthalenesulfonic acid and aniline on a conventional macroporous resin Amberlite XAD4 and the other two newly-developed hypercrosslinked resins NDA101 and NDA100 were investigated in a single or binary batch system at 293 K and 313 K,respectively.All the adsorption isotherms of 2-naphthalenesulfonic acid and aniline on the test resins in both systems can fit well with the Langmuir equation,indicating that the adsorption is a favorable process.At the identical equilibrium concentration,the amount of aniline adsorbed on polymeric resins in the single system is higher than that in the binary system because of the competitive adsorption between 2-naphthalenesulfonic acid and aniline on the resin surface.However,the uptake amount of 2-naphthalenesulfonic acid in the binary system is markedly larger than that in the single system,which is presumably due to the cooperative effect arisen from the electrostatic interaction between 2-naphthalenesulfonic acid and aniline adsorbed on the resin surface.The simultaneous adsorption system was proven to be helpful for the selective adsorption toward 2-naphthalenesulfonic acid due to its larger selective index.     

EFFECT OF WEAK INTERACTIONS ON PHENOL ADSORPTION FROM AQUEOUS SOLUTIONS BY AMINATED POLYMERIC ADSORBENTS

Adsorption behaviors of phenol from aqueous solutions have been investigated in batch systems at 303 K and 318 K respectively, using hypercrosslinked polymeric adsorbent （CHA111）, aminated hypercrosslinked polymeric adsorbents （NDA101, NDA103, NDA105） and weakly basic polymeric adsorbent （D301） with a view to studying the effect of hydrogen bonding and Van der Waals interactions between adsorbate and the adsorbent. All adsorption isotherms can be well fitted by Langmuir and Freundlich equations. Compared with D301 driven by hydrogen bonding interaction only and CHA111 driven by Van der Waals interaction only, phenol adsorption on aminated adsorbents driven by both hydrogen bonding and Van der Waals interactions were apparently different, i.e., negative effect for NDA105, positive effect for NDA101 and synergistic effect for NDA103. In this synergistic action, some weak interactions would contribute more or less to the adsorption than they work individually.     

Modeling synergistic adsorption of phenol/aniline mixtures in the aqueous phase onto porous polymer adsorbents

The adsorption equilibria of phenol and aniline on nonpolar polymer adsorbents (NDA-100, XAD-4, NDA-16 and NDA-1800) were investigated in single- and binary-solute adsorption systems at 313 K. The results showed that all the adsorption isotherms of phenol and aniline on these adsorbents can be well fitted by Freundlich and Langmuir equations, and the experimental uptake of phenol and aniline in all binary-component systems is obviously higher than predicted by the extended Langmuir model, arising presumably from the synergistic effect caused by the laterally acid-base interaction between the adsorbed phenol and aniline molecules. A new model (MELM) was developed to quantitatively describe the synergistic adsorption behavior of phenol/aniline equimolar mixtures in the binary-solute systems and showed a marked improvement in correlating the binary-solute adsorption of phenol and aniline by comparison with the widely used extended Langmuir model. The newly developed model confirms that the synergistic coefficient of one adsorbate is linearly correlated with the adsorbed amount of the other, and the larger average pore size of adsorbent results in the greater synergistic effect of phenol/aniline equimolar mixtures adsorption.     

SYNERGISTIC INTERACTIONS ON PHENOL ADSORPTION FROM AQUEOUS SOLUTIONS BY POLYMERIC ADSORBENTS

In this paper, the adsorption behaviors of phenol on polymeric adsorbents (Amberlite XAD4, NDA101, and D301)were investigated in batch system at 293, 303, and 313K, respectively. As the results shown, the adsorption isotherms of phenol on all adsorbents can be well fitted by Langmuir and Freundlich equations, which indicate a favorable and exothermic process. The adsorption capacity on a newly developed aminated adsorbent, NDA101, on which adsorption could be achieved by both hydrogen bonding interaction and π-π interaction, are higher than that on a weak base adsorbent, D301, on which adsorption could be achieved by hydrogen bonding interaction only, and on a nonpolar adsorbent, XAD4, on which adsorption could be achieved by π-π interaction only. The results of this paper indicate that the synergistic effect of some weak interactions, which occur simultaneously would contribute more to the adsorption than that occur individually.     

超高交联吸附树脂对芳香有机物的吸附机理

通过3种吸附树脂AmberliteXAD-4、AM-1和JX101对芳香化合物苯胺、苯酚和苯甲酸在不同温度下的吸附特征,利用前线轨道理论进行了合理解释。结果表明,吸附剂表面进行适当的修饰,可以改变吸附剂的LUMO或HOMO,使吸附质分子与吸附剂表面的功能基产生化学作用,从而产生额外的化学吸附量,为优化设计吸附剂提供了理论指导。     

SINGLE AND BINARY ADSORPTION PERFORMANCE OF SALICYLIC ACID AND 5-SULFOSALICYLIC ACID ONTO HYPERCROSSLINKED POLYMERIC ADSORBENTS

Single and binary adsorption behaviors of salicylic acid and 5-sulfosalicylic acid onto hypercrosslinked polymeric adsorbents, i.e. NDA-101 and NDA-99 were investigated. The Freundlich model can successfully describe all the adsorption isotherms tested, which indicates a favorable and exothermic adsorption process. The adsorption of salicylic acid relies on π-π interaction, while the electrostatic interaction further influences the adsorption of 5-sulfosalicylic acid onto NDA-99. The adsorptive capacity of salicylic acid on NDA-99 decreases but increases on NDA-101 with 5-sulfosalicylic acid as the background component in a binary solute system. The amount of 5-sulfosalicylic acid adsorbed was decreased with the increase in initial concentration of salicylic acid on both adsorbents. The competition for the adsorption sites is considered to be predominant in the solid-to-liquid interaction process. The adsorption selectivity of salicylic acid onto NDA-101 is higher than onto NDA-99 by more than an order of magnitude. Thus, combination technique involving NDA-101 followed by NDA-99 can be effectively applied to separate and recover salicylic acid and 5-sulfosalicylic acid from wastewater.     

Competitive adsorption isotherm modelling of heterocyclic nitrogenous compounds,pyridine and quinoline,onto granular activated carbon and bagasse fly ash

In the present study, simultaneous adsorption of quinoline and pyridine onto adsorbents such as granular activated carbon (GAC) and bagasse fly ash (BFA) from pyridine–quinoline binary aqueous solution was studied at various temperatures (288–318 K). Gathered equilibrium adsorption data were further analysed using various multicomponent competitive isotherm models such as non-modified and modified competitive Langmuir isotherms, extended-Langmuir isotherm, extended-Freundlich model, Sheindorf–Rebuhn–Sheintuch (SRS) model, and non-modified and modified competitive Redlich–Peterson isotherm model. It was observed that increase in pyridine concentration decreased the total adsorption yield and the individual adsorption yield for both the quinoline and pyridine for both the adsorbents GAC and BFA at all the temperatures studied. Identical trend was observed during the equilibrium uptake of pyridine on to GAC and BFA with an increase in quinoline concentration. The extended-Freundlich model satisfactorily represented the binary adsorption equilibrium data of quinoline and pyridine onto GAC and BFA.     

Removal of Phenol by Using Montmorillonite,Clinoptilolite and Hydrotalcite

This work is to study the removal of phenol from aqueous solutions by adsorption using three different adsorbents, clinoptilolite, montmorillonite, and hydrotalcite (HT). Except for montmorillonite, the other adsorbents were treated. Clinoptilolite was modified using cetyltrimethylammonium bromide (CTAB) and hydrotalcite was calcined by heating to 550C. Adsorption isotherms of phenol on all of the mentioned adsorbents was determined by using the batch equilibration technique and indicated that, the adsorption behavior could be modelled by using the Modified Freundlich equation. The differences observed in the isotherms were explained by the variations in adsorbent-adsorbate interactions under the effects of the different surface structures of adsorbents and the pH dependent ionization behavior of phenol. Calcined hydrotalcite (HTC) was found to be the best among the studied adsorbents since it can adsorb 52% of phenol from a solution containing initially 1 g/L phenol for the 1/100 adsorbent solution ratio while the others can adsorb only 8% of phenol for the same concentration and adsorbent solution ratio.     

Adsorption of aniline,phenol, and chlorophenols on pure and modified bentonite

In the present study, pure bentonite and bentonite modified by HNO₃, EDTA, and HDTMA are adsorbents. The changes on the surfaces of bentonite samples are studied by IR spectroscopy. The adsorption of aniline, phenol, and phenol derivatives on these adsorbents is examined by means of gas chromatography. As the result of these examinations, it is seen that the adsorption capacities of clay-organic complexes (bentonite-EDTA and bentonite-HDTMA) are higher than those of bentonite-HNO₃ and pure bentonite.