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1.
Spherical crosslinked polystyrene-isocyanuric acid resin was synthesized by reaction of chloromethylated polystryene with isocyanuric acid.The sorption isotherms of phenol from aqueous solution and cyclohexane solution onto the resin were measured.It is of interest to notice that the resin sorbed phenol efficiently though its specific surface area was 0 and did not swell in water,and the sorption capactity from aqueous solution was close to that of phenol onto XAD-4 at the same equilibrium concentration.Sorption enthalpies calculated from the isotherms according to the Clausius-Clapeyron equation were -21-25kJ/mol and -39-41kJ/mol respectively.These values impled that the sorption processes were based on hydrogen bonding.In addition.the details of the hydrogen bonding between the active sites of the resin and phenol were suggested. 相似文献
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大孔交联聚(对乙烯基苄基苯基醚)树脂对苯酚的吸附机理 总被引:1,自引:0,他引:1
由氯甲基化聚苯乙烯合成了大孔交联聚(对乙烯基苄基苯基醚)树脂(简称为苯基醚树脂), 测定了其对正己烷和水中苯酚的吸附等温线, 计算了吸附焓. 同时, 比较了聚(对乙烯基苄甲醚)、苯基醚树脂、聚(对乙烯基苄基对硝基苯基醚)和聚(对乙烯基苄基对甲基苯基醚)对正己烷中苯酚的吸附性能以及氯甲基化聚苯乙烯和苯基醚树脂对水中苯酚、2,3,5-三甲基苯酚和对硝基甲苯的吸附性能. 结果表明, 苯基醚树脂是通过氢键吸附正己烷溶液中苯酚的, 而其对水中苯酚的吸附是基于氢键和疏水作用的协同. 相似文献
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The adsorption isotherms of caffeine from aqueous solution onto three hydrogen donating adsorbents-hydroxypolystyrene,polystryene-azo-pyrogallol,and D72 resin-were measured.The adsorption enthalpies calculated from the isotherms according to the Clausisu-Clapeyron equation were -24-36kJ/mol,-32-37kJ/mol,and -19-24kJ/mol respectively.These values implied that the adsorption processes were based on hydrogen bonding.Furthermore.the mechanism of the adsorption of caffeine onto D72 resin was studied by IR spectra and the small molecular model experiments,and the results showed that the adsorption of caffeine onto hydrogen donating adsorbents was based on hydrogen bonding. 相似文献
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XU Mancai SHI Zuoqing XIE Xianglin XU Mingcheng ZENG Ying LIANG Liyan HE Binglin 《Chinese Journal of Reactive Polymers》2000,(1)
1. INTRODUCTIONHydrogen bonding is a useful mechanism for adsorptive separation. The low enemy of thisbond ensures reversibility, while the directionality and the short range of this bond conferselectivity. The adsorption of hydrogen donating solutes onto an adsorbent capable of acceptinghydrogenedmberlite XAD-7, an adsorbent consisted of polycarboxylic ester--based onhydrogen bonding has been examined in detail 11-41. However, the adsorption of hydrogenaccepting solutes onto polymeric a… 相似文献
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采用二甲胺为功能化试剂,化学修饰氯甲基化苯乙烯-二乙烯基苯共聚物合成了大孔交联聚(N-对乙烯基苄基二甲胺)树脂,测得树脂的氯含量由4.2mmol/g降低到0.24mmol/g,树脂的弱碱交换量为4.0mmol/g,说明氯甲基化苯乙烯-二乙烯基苯共聚物发生胺化反应完全。在水溶液中,测定了大孔交联聚(N-对乙烯基苄基二甲胺)树脂对苯酚的吸附等温线,发现吸附平衡数据符合Freundlich等温吸附方程,相关系数大于0.99。计算得到在吸附量为15、20和25mg/g时,等量吸附焓在-20.81~-30.74kJ/mol范围内,吸附自由能和吸附熵均小于0,说明吸附过程中存在氢键作用,吸附是自发、混乱度变小的过程。比较树脂对水溶液中苯酚、对硝基苯酚和对硝基甲苯的吸附性能以及树脂对水、环己烷、乙醇和乙酸乙酯溶液中苯酚的吸附性能,进一步说明大孔交联聚(N-对乙烯基苄基二甲胺)树脂对水溶液中苯酚的吸附是基于疏水作用和氢键作用协同的机理。 相似文献
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HUANG Jiangou XU Mancai ** LI Haitao SHI Zuoqing HE Binglin College of Chemistry Chemical Engineering Hunan Normal University Changsha The State Key Laboratory of Functional Polymer Materials for Adsorption Separation Institute of Polymer Chemistry Nankai University Tianjin 《Chinese Journal of Reactive Polymers》2002,(2)
1. INTRODUCTION Adsorption capacity and selectivity are improved when some ion exchange groups or hydrogen bonding acceptor or/and donors are introduced into common polymeric adsorbents [1~5]. R. F. Shi et al have synthesized a series of bifunctional ads… 相似文献
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Three polymeric adsorbents with hydrogen bonding acceptors, methylamine,N-methyl-acetamide and aminotri(hydroxymethyl)methane modified resins are synthesized fromchloromethylated X-5 resin. Adsorption isotherms of phenol and theophylline onto the three modifiedresins and the original X-5 resin from aqueous solution are measured. The results show thatadsorption of compounds with hydrogen bonding donor onto methylamine and N-methylacetamidemodified resins is enhanced as compared with that onto X-5 resin, and adsorption mechanismbetween the adsorbents and the adsorbates is mainly based on hydrogen bonding and hydrophobicinteraction. While adsorption of compounds with hydrogen bonding donor ontoaminotri(hydroxymethyl)methane modified resin is lowered as compared with that onto X-5 resin, andadsorption mechanism between the adsorbent and the adsorbates is mainly based on hydrophobicinteraction. 相似文献
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Synthesis, characterization, and adsorption behavior of aniline modified polystyrene resin for phenol in hexane and in aqueous solution 总被引:2,自引:0,他引:2
Macroporous crosslinked poly(p-vinylbenzylaniline) (PVBA) was synthesized and its adsorption isotherms for phenol in hexane and in aqueous solution were comparatively measured. It was shown that the adsorption isotherms in hexane were straight lines and passed through the origin, whereas those in aqueous solution could be simulated by Freundlich isotherms. Adsorption enthalpies of phenol onto PVBA were calculated, and the results indicated that the adsorption was an exothermic process. Comparison of the adsorption behaviors of PVBA, poly(p-vinylbenzylmethylamine) (PVBMA), and poly(p-vinylbenzyl-p-nitroaniline) (PVBNA) for phenol in hexane suggested that hydrogen bonding and pi-pi stacking were primarily responsible for the adsorption, the nitrogen atom and benzene ring of PVBA acted as hydrogen bonding acceptors and formed hydrogen bonding with the hydrogen atom of hydroxyl group of phenol. Investigation of the adsorption mechanism in aqueous solution revealed that hydrogen bonding and hydrophobic interaction were the main driving forces. 相似文献
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测定了聚(对乙烯基苄基己内酰胺)吸附树脂对正庚烷溶液中苯酚的吸附等温线,发现吸附等温线符合Freundlich等温吸附方程,相关系数大于0.99.根据热力学函数关系计算了等量吸附焓、Gibbs吸附自由能和吸附熵,等量吸附焓在30~40kJ/mol之间,推测吸附过程为氢键吸附.通过比较树脂对正庚烷中苯酚和邻硝基苯酚的吸附性能的差别,进一步论证了树脂对非水体系中酚类物质的吸附是基于氢键作用的机理.同时,聚(对乙烯基苄基己内酰胺)树脂对正庚烷溶液中苯酚的吸附相对水溶液中苯酚的吸附有更低的吸附焓变、吸附自由能变和吸附熵变. 相似文献
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A Strongly hydrophilic hydrogen-bonding adsorbent-macroporous crosslinked Poly(Nvinyl-acetamide),which contain both hydrogen bond acceptor and donator,was synthesized.Adsorption mechanism and dynamic adsorption of tannin from aqueous solution onto the adsorbent were investigated.Most of the differntial adsorption heats for various adsorption capacities calculated from the adsorption isotherms according to Clapeyron-Clausius equation lay in the range of hydrogen bond energy(8-50J/mol).Adsorption properties of the adsorbent were studied in detail.These results revealed a hydrogen bonding mechanism of the adsorption of tannin from aqueous solution onto the adsorbent.The result of the dynamic adsorption of tanning with the initial concentration under 600mg/L showed that the adsorption rate of tannin exceeded 90% when the flow rate was 3BV/h and the effluent volume reached 100BV.Therefore,the developed hydrogen-bonding adsorbent-macroporous crosslinked poly(N-vinyl-acetamide)-is an excellent adsorbent to remove tannin from extract of natural products,and has great value in application. 相似文献
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Isotherm analysis of phenol adsorption on polymeric adsorbents from nonaqueous solution 总被引:1,自引:0,他引:1
Macroporous poly(methyl methacrylate-co-divinylbenzene) (PMMA), interpenetrating polymer adsorbent based on poly(styrene-co-divinylbenzene) (PS) and poly(methyl methacrylate-co-divinylbenzene) (PMMA/PS), and macroporous cross-linked poly(N-p-vinylbenzyl acetylamide) (PVBA) were prepared for the adsorption of phenol from cyclohexane. The sorption isotherms of phenol on the three polymeric adsorbents were measured and fitted to Langmuir and Freundlich isotherms. It is shown that the Langmuir isotherm, which is based on a homogeneous surface model, is unsuitable to describe the sorption of phenol on the adsorbents from nonaqueous solution and the Freundlich equation fits the tested three adsorption systems well. The isosteric enthalpy was quantitatively correlated with the fractional loading for the sorption of phenol onto the three polymeric adsorbents. The surface energetic heterogeneity patterns of the adsorbents were described with functions of isosteric enthalpy. The results showed that the tested three polymeric adsorbents exhibited different surface energetic heterogeneity patterns. The initial isosteric enthalpy of phenol sorption on polymeric adsorbent has to do with the surface chemical composition and is free from the pore structure of the polymeric adsorbent matrix. Forming hydrogen bonds between phenol molecules and adsorbent is the main driving force of phenol sorption onto PVBA and PMMA adsorbent from nonaqueous solution. When phenol is adsorbed on PMMA/PS, pi-pi interaction resulting from the stacking of the benzene rings of the adsorbed phenol molecules and the pendant benzene ring of adsorbent is involved. 相似文献
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The sorption of traces of silver ions onto polyurethane foam (PUF) has been investigated in detail. Maximum sorption of silver (K(d)=6109 cm(3) g(-1), %sorption>97.5%) has been achieved from 1 M nitric acid solution after equilibrating silver ions with approximately 29 mg PUF for 20 min. The kinetics and thermodynamics of the sorption of silver ions onto PUF have also been studied. The sorption of silver ions onto PUF follows a first-order rate equation, which results as 0.177 min(-1). The variation of sorption with temperature yields the values of DeltaH=-56.1+/-3.2 kJ mol(-1), DeltaS=-159.7+/-10.5 J mol(-1) K(-1) and DeltaG=-8.68+/-0.09 kJ mol(-1) at 298 K with a correlation factor gamma=0.9919. The sorption data were subjected to different sorption isotherms. The sorption follows Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The values of Langmuir isotherms Q=65.4+/-1.5 mumol g(-1) and b=(4.79+/-1.16)x10(4) dm(3) mol(-1) have been evaluated for Langmuir sorption constants, whereas the Freundlich sorption isotherm gives the value 1/n=0.12+/-0.02 and A=0.15+/-0.03 mmol g(-1). The D-R parameters computed were beta=-0.000817+/-0.000206 mol(2) kJ(-2), X(m)=76.8+/-8.7 mumol g(-1) and E=24.7+/-3.2 kJ mol(-1). The influence of common ions on the sorption was also examined. It is observed that Hg(II), thiourea, Al(III), thiocyanate and thiosulphate reduce the sorption, whereas Cu(II), citrate and acetate ions enhance the sorption significantly. It can be concluded that PUF may be used to remove traces of silver ions from its very dilute solutions or for its preconcentration from aqueous acidic solutions. 相似文献
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Two hydrogen-bonding adsorbents-macroporous crosslinked poly(P-nitrostyrene)and poly(p-vinylbenzyl amide)-were synthesized,and the adsorption property of phenol from cyclohexane solution onto the adsorbents was studied,The differential adsorption heasts for varied adsorption capacities calculated from the adsorption isotherms according to the Claperyron-Clausius equation lay in the range of hydrogen bond energy (8-50kJ/mol),The adsorption capaccity of o-nitrophenol in cyclohexane was moch less than that of phenol under the same condition.The adsorption capacity of phenol from cyclohexane onto polyacrylonitrile was much less than that onto poly(p-nitrostyrene)or poly(p-vinylbenzyl amide),All these results revealed that adsorption of phenol from cyclohexane by poly(p-nitrostyrene) or poly(p-vinylbenzyl amide)is based on hydrogen-bonding. 相似文献
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XU Mancai WANG Cairong SHI Zuoqing XU Mingcheng ZHANG Shang LI Haitao. FAN Yunge HE Binglin. 《Chinese Journal of Reactive Polymers》2000,(1)
1 INTRODUCTIONHydrogen-bonding adsorbents are functional polymers for adsorption and separation via theformation of hydrogen bond between the adsorbentS and adsorbates. Because hydrogen bond is astrong intermolecular (or intramolecular) force, hydrogen-bonding adsorbents have strong potentto adsorbing adsorbates with which can form hydrogen bond. In our previous work, three seriesof hydrogen-bonding adsorbents have been studied, which were adsorbents with hydrogendonator, adsorbentS with … 相似文献
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LI Xiaotao Pan Bingcai Pan Bingjun Zhang Weimin Meng Fanwei Chen Jinlong Zhang Quanxing 《反应性高分子(英文版)》2005,14(1):44-51
X-ray photoelectron spectroscopy (XPS ) was adopted to elucidate sorption mechanism of phenol and p-nitrophenol onto a weakly anion exchanger D301. The distribution of specific forms of tertiary amino group on D301 was obtained and effect of free tertiary amino group on phenol sorption onto D301 was discussed. The result indicated that the percent of the protonated tertiary amine group on polymeric matrix was much lower than the reference compound N,N-dimethylbenzylamine at an identical pH value in solution due to the much lower activity degree of hydrogen ion in inner resin phase than in the external solution. Less free amino group on D301 results in less sorption capacity of phenol and p-nitrophenol in an acidic solution. Under the experimental conditions both phenol sorption onto D301 can be explained as solid extraction and the distribution coefficient varies linearly with the content of free amino group on D301. 相似文献
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LI Xiaotao Pan Bingcai Pan Bingjun Zhang Weimin Meng Fanwei Chen Jinlong Zhang Quanxing . State Key Laboratory of Pollution Control Resources Reuse School of the Environment Nanjing University Nanjing China . Department of Science Technology State Environmental Protection Agency Beijing China 《Chinese Journal of Reactive Polymers》2005,(Z1)
1. INTRODUCTION Phenolic compounds are pollutants encountered frequently in water system. Some of them, such as phenol and p-nitrophenol, have been listed as priority pollutants in many countries. How to remove them completely from the polluted water is of significant concern to environmental scientists. Up to now many technologies such as biodegradation, oxidation and adsorption are available to remove phenolic compounds from the receiving water [1~4]. In the past two decadesphenol sorpt… 相似文献