新型树脂基水合锰氧化物对水体中磺胺嘧啶的降解去除

以大孔强碱阴离子交换树脂D201为载体, 采用离子交换和氧化还原方法制备了一种新型树脂基水合锰氧化物材料HMO-201. 考察了不同pH、 离子强度和溶解性有机质(DOM)含量条件下, 该材料对水体中磺胺嘧啶(SD)的去除能力. HPLC-MS分析表明, SD的高效去除是通过HMO-201的降解而非吸附方式实现的. 实验结果表明, pH为1.0时HMO-201在120 min内对0.01 mmol/L SD的去除效率为99.9%, 反应符合表观一级动力学模型; 体系的离子强度和DOM含量变化对SD的去除效率均无显著影响. 模拟环境离子强度和DOM浓度, 连续10批次实验中SD废水的去除效率在240 min内均大于99%; HMO-201的柱动态降解装置连续处理SD溶液2000床体积, 依然未检出SD. 表明HMO-201材料具有较稳定的重复利用性, 对环境中普遍存在的磺胺类抗生素药物具有着高效的降解去除效果, 具有广泛的应用前景.     

树脂对化工废水中有毒有机化合物的吸附作用机理与技术研究

超高交联吸附树脂对多种芳香有机化合物较高的吸附容量主要源于其密集的微孔和双峰孔分布.对大孔吸附树脂及超高交联吸附树脂采用不同极性功能基团进行化学修饰可以制得系列离子交换与吸附双重功能吸附树脂,该类树脂对亲水性有机污染物同时具有疏水、静电、络合等多重作用.丙烯酸酯类吸附树脂在吸附芳香磺酸盐时,树脂的骨架和功能基团对吸附过程都有重要的贡献.     

MODIFICATION OF X-5 RESIN AND ADSORPTION PROPERTY OF THE MODIFIED RESINS

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…     

Phenol removal from aqueous solution by adsorption and ion exchange mechanisms onto polymeric resins

The removal of phenol from aqueous solution was evaluated by using a nonfunctionalized hyper-cross-linked polymer Macronet MN200 and two ion exchange resins, Dowex XZ (strong anion exchange resin) and AuRIX 100 (weak anion exchange). Equilibrium experimental data were fitted to the Langmuir and Freundlich isotherms at different pHs. The Langmuir model describes successfully the phenol removal onto the three resins. The extent of the phenol adsorption was affected by the pH of the solution; thus, the nonfunctionalized resin reported the maximum loading adsorption under acidic conditions, where the molecular phenol form predominates. In contrast both ion exchange resins reported the maximum removal under alkaline conditions where the phenolate may be removed by a combined effect of both adsorption and ion exchange mechanisms. A theoretical model proposed in the literature was used to fit the experimental data and a double contribution was observed from the parameters obtained by the model. Kinetic experiments under different initial phenol concentrations and under the best pH conditions observed in the equilibrium experiments were performed. Two different models were used to define the controlling mechanism of the overall adsorption process: the homogeneous particle diffusion model and the shell progressive model fit the kinetic experimental data and determined the resin phase mechanism as the rate-limiting diffusion for the phenol removal. Resins charged after the kinetic experiments were further eluted by different methods. Desorption of nonfunctionalized resin was achieved by using the solution (50% v/v) of methanol/water with a recovery close to 90%. In the case of the ion exchange resins the desorption process was performed at different pHs and considering the effect of the competitive ion Cl⁻. The desorption processes were controlled by the ion exchange mechanism for Dowex XZ and AuRIX 100 resins; thus, no significant effect for the addition of Cl⁻ under acidic conditions was observed, while under alkaline conditions the total recovery increased, specially for Dowex XZ resin.     

EFFECT OF pH ON THE ADSORPTION OF p-AMINOBENZOIC ACID ON POLYSTYRENE-BASED ADSORBENTS

In the present study the adsorptive properties of p-aminobenzoic acid with hypercrosslinked and multi-functional polymeric adsorbents at different solution pHs were systematically investigated in accordance with the particular physicochemical characteristics of the aromatic amphoteric compound involving both Lewis acid and Lewis base functional groups. It was found that the equilibrium adsorption data of the three polymeric adsorbents fitted well in the Langmuir and Freundlich isotherm equations. Studies at various pH levels indicate that the capacity of the adsorbents for adsorption of the ionic forms of adsorbate is less than that for the corresponding neutral species. At pH 3.78, the adsorption capacities of the three adsorbents are the highest. Whereas the adsorption property of multi-functional polymeric adsorbent NJ-99 is the largest, which may be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of p-aminobenzoic acid. The trend of the adsorption capacities of the three adsorbents towards p-aminobenzoic acid with the solution pH is in accord with the dissociation curve of the neutral molecular p-aminobenzoic acid. The adsorption forces include π-π interaction, hydrogen-bonding interaction and electrostatic attraction or repulsion when there exist the molecular and ionic adsorbing species at different pHs in aqueous solution.     

丙烯酸酯树脂对泰乐菌素的吸附

通过调节单体、交联剂和致孔剂的种类及数量合成了一系列具有不同孔结构的丙烯酸酯树脂,并从中选出具有典型吸附差异的2种树脂,拥有适合的孔分布结构的三羟甲基丙烷三甲基丙烯酸甲酯(TRIM)聚合树脂(1#)和含酰胺基的三烯丙基异氰尿酸酯(TAIC)与TRIM共聚树脂(5#),与商业化大孔丙烯酸酯树脂XAD-7作比较,研究了丙烯酸酯树脂对泰乐菌素的吸附行为和机理。结果表明,树脂1#表现出了对泰乐菌素有最高的吸附量。3种吸附剂的吸附量随溶液pH值的升高呈增加趋势。吸附剂的吸附能力随溶液NaCl离子浓度的增强而提高,而对CuCl2则呈相反趋势,这是因为疏水作用和孔径排斥效应的贡献。泰乐菌素在3种吸附剂上的吸附动力学均符合准二级动力学模型,吸附等温线符合Langmuir模型。升高温度可以使树脂吸附能力增强,可能是“溶剂替代”效应所致。     

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.     

Investigations on the adsorbents for uremic middle molecular toxins (Ⅱ)——Influences of crosslinking agent chain length on the adsorption capacities of crosslinked chitosan adsorbents

Chitosan resins, which clinically served as adsorbents in hemoperfusion therapy, were prepared with reversed-phase suspension methodology using three differently structured crosslinking agents, methanal, glyoxal and glutaraldehyde. And the glyoxal and glutaraldehyde crosslinked chitosan resins were reduced with NaBH4 afterwards. By analyzing the results from FTIR and SEM, it was found that the reduction treatment to the adsorbents efficiently improved the chemical stability of these chitosan resins, and the shifts in crosslinking agents exerted influences over the morphologies of the adsorbents obviously. After being put to use in the adsorption tests upon some model uremic middle molecular toxins and BSA in vitro, all three adsorbents demonstrated a fairly realistic adsorption capability to the model toxins but little to BSA. And the adsorption process reached the equilibrium in a clinically qualified short time. But the adsorption capacities of these adsorbents to the model toxins were quite different. It     

树脂填充聚醚砜纤维吸附剂对牛血清蛋白吸附性能的研究

重点研究树脂填充聚醚砜(PES)纤维吸附剂与模型蛋白质牛血清蛋白(BSA)之间的吸附与脱附行为.结果表明,蛋白质BSA在树脂填充PES纤维吸附剂中的平衡吸附过程较好地符合朗格缪尔吸附模型,树脂Lewatit CNP80ws填充PES吸附剂的最大吸附容量约为139mg BSA/g吸附剂.表面具有开孔结构的树脂填充PES纤维吸附剂的吸附速率较快,在不同结构纤维吸附剂中BSA的扩散系数在1·82×10-14~8·7×10-14m2/s范围内变化.另外,考察了BSA溶液的pH与洗脱剂等因素对吸附剂吸附与脱附性能的影响,研究结果对蛋白质的实际分离纯化具有重要的参考价值.     

MODIFICATION OF X-5 RESIN AND ADSORPTION PROPERTY OF THE MODIFIED RESINS

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.     

Ion-exchange resins in non-aqueous solvents-III Solvent-uptake properties of ion-exchange resins and related adsorbents

Solvent-uptake properties for several synthetic resins and common adsorbents were determined by the centrifugation method. Data are reported for eighteen different solvents, which include water and the common polar and non-polar organic solvents. The cation-exchange resins are of two varieties: the microreticular or gel type and the macroreticular or porous type. The latter resin being rigid and porous takes up all types of solvents, whereas the former resin, which relies on swelling of the resin matrix, does not take up the nonpolar solvents. Data for the H(+) form and Na(+) form macroreticular resin are compared. Unsulphonated polystyrene-divinylbenzene polymers which possess similar micro- and macroreticular properties to the cation-exchange resins were also studied in the same solvents. The swelling properties of these non-polar resins are compared with each other and with the polar cation resins. Other adsorbents, which are frequently used as supports in chromatography were also examined in the same solvents. Several of these have large average pore diameters and surface areas like the macroreticular resin.     

Investigations on the adsorbents for uremic middle molecular toxins (II)

Chitosan resins, which clinically served as adsorbents in hemo perfusion therapy, were prepared with reversed-phase suspension methodology using three differently structured crosslinking agents, methanal, glyoxal and glutaraldehyde. And the glyoxal and glutaraldehyde crosslinked chitosan resins were reduced with NaBH₄ afterwards. By analyzing the results from FTIR and SEM, it was found that the reduction treatment to the adsorbents efficiently improved the chemical stability of these chitosan resins, and the shifts in crosslinking agents exerted influences over the morphologies of the adsorbents obviously. After being put to use in the adsorption tests upon some model uremic middle molecular toxins and BSA in vitro, all three adsorbents demonstrated a fairly realistic adsorption capability to the model toxins but little to BSA. And the adsorption process reached the equilibrium in a clinically qualified short time. But the adsorption capacities of these adsorbents to the model toxins were quite different. It had been found that with the growing of fatty chain length of crosslinking agent, these adsorbents showed a gradually increased adsorption capacity to the model toxins, and the glutaraldehyde crosslinked chitosan resin behaved best.     

吸附树脂的修饰官能团设计及其吸附机理研究

利用AM1半经验计算法计算出用不同官能团修饰的聚苯乙烯型吸附树脂的前线轨道能量值.设计筛选出合适的官能团,根据吸附质的分子尺寸,修饰合成出具有匹配孔径、较大比表面积的吸附树脂.在303K下,测定了它们对不同取代基的酚类化合物的吸附等温线.以Amberlite XAD-4作参照,比较了吸附剂的吸附效果,并阐明了吸附机理.     

石墨烯基吸附剂的设计及其对水中抗生素的去除

抗生素的大量使用,所带来的环境污染问题受到广泛关注。吸附法因去除效率高、普遍适用性强,呈现出广阔的应用前景,开发新型吸附剂是高效能吸附处理的关键。近年来石墨烯优良的物理和化学性质以及吸附性能,使其成为重要的抗生素吸附剂。由于石墨烯自身的局限性以及对石墨烯吸附剂处理效能和稳定性的要求,基于石墨烯设计开发了多种石墨烯基吸附材料。而目前基于水体中抗生素的石墨烯基复合材料的设计、合成及其吸附作用机制缺乏相关的系统性综述。本文综述了目前水体中抗生素的危害,针对石墨烯基复合吸附材料中,广泛关注的磁性石墨烯吸附剂、聚合物/石墨烯吸附剂、三维石墨烯凝胶和石墨烯/生物炭吸附剂的设计和制备方法进行了总结和概述,并阐述了石墨烯基吸附材料对水体中抗生素的主要吸附作用机制。最后,本文对石墨烯基吸附材料去除水体中抗生素未来的发展方向进行了展望。     

Adsorption of gases on adsorbents of various nature and porous structure at high pressures

The isotherms of excess adsorption of argon, nitrogen, and carbon dioxide on adsorbents with various porous structures (active carbon AU-71, polymeric sorbent MN-200, and synthetic zeolite NaA) were measured on the precision volumetric-gravimetric device in the pressure range of 0.1—150 MPa and at temperatures 300—400 K. The results of determination of the adsorption volumes of the studied adsorbents were compared using two methods. The first method is based on the Dubinin-Radushkevich equation, whereas the second one involves a conditional division of the weight of the substance in an ampule into the adsorbed portion and the part existing in the gas phase. The behavior of the adsorbed substance is described by the equation of adsorption of complete content corresponding to the physics of the adsorption process. The relation of the parameters of the empirical Dubinin—Radushkevich equation to the energy characteristics of the system was established.     

辛巴蓝F-3GA修饰的啤酒废酵母菌亲和吸附溶菌酶

利用j嗪染料辛巴蓝F-3GA修饰经戊二醛交联的啤酒废酵母菌,得到一种新型染料亲和吸附剂.辛巴蓝F-3GA的固载量为161.1 mg/g.以溶菌酶为研究对象,考察吸附时间、酶初始浓度、pH值、离子强度等因素对吸附率的影响.结果表明:当pH=7.0时,其对溶菌酶有较高的吸附量(229.1 mg/g),吸附性能明显优于未接枝...     

大孔树脂对磺酸类化合物吸附行为的研究

用4种大孔树脂ND-022，ND-900，NDA-99和NDA-100作为吸附剂，分别对水溶液中甲基磺酸钠、苯磺酸钠、对甲基苯磺酸钠和2-萘磺酸钠等磺酸盐进行吸附．探讨了溶液的初始pH值对不同类型树脂吸附磺酸类物质的影响，并通过动态吸附实验研究了SO4^2-对树脂吸附磺酸盐的影响．实验结果表明，复合功能树脂NDA-99对磺酸类化合物具有良好的吸附性能，且其选择性优于弱碱树脂ND-900，这为进一步研究大孔树脂对磺酸类物质的吸附机理和实际工业应用提供了一定的理论依据。     

Sustainable adsorptive removal of antibiotic residues by chitosan composites: An insight into current developments and future recommendations

During COVID-19 crisis, water pollution caused by pharmaceutical residuals have enormously aggravated since millions of patients worldwide are consuming tons of drugs daily. Antibiotics are the preponderance pharmaceutical pollutants in water bodies that surely cause a real threat to human life and ecosystems. The excellent characteristics of chitosan such as nontoxicity, easy functionality, biodegradability, availability in nature and the abundant hydroxyl and amine groups onto its backbone make it a promising adsorbent. Herein, we aimed to provide a comprehensive overview of recent published research papers regarding the removal of antibiotics by chitosan composite-based adsorbents. The structure, ionic form, optimum removal pH and λ_max of the most common antibiotics including Tetracycline, Ciprofloxacin, Amoxicillin, Levofloxacin, Ceftriaxone, Erythromycin, Norfloxacin, Ofloxacin, Doxycycline, Cefotaxime and Sulfamethoxazole were summarized. The development of chitosan composite-based adsorbents in order to enhance their adsorption capacity, reusability and validity were presented. Moreover, the adsorption mechanisms of these antibiotics were explored to provide more information about adsorbate-adsorbent interactions. Besides the dominant factors on the adsorption process including pH, dosage, coexisting ions, etc. were discussed. Moreover, conclusions and future recommendations are provided to inspire for further researches.     

胺修饰酚醛树脂对酸性橙Ⅱ的吸附性能研究

研究了自制胺修饰酚醛树脂(AMPF)对水溶性染料酸性橙II的吸附性能,探讨了pH值、温度、浓度等因素对酸性橙吸附性能的影响。结果表明,AMPF与市售大孔树脂D296和D301相似,对酸性橙均具有较强的吸附能力。温度升高有利于AMPF对酸性橙的吸附;酸性橙浓度升高,吸附量增大。AMPF对酸性橙的吸附符合Boyd液膜扩散控制。各种树脂对酸性橙的平衡吸附数据符合Langmuir方程和Freundlich等温式,其相关系数大于0.98,n均大于1,表明为优惠吸附。     

Effect of Pore Size Distribution and Amination on Adsorption Capacities of Polymeric Adsorbents

Polymeric adsorbents with different properties were synthesized via suspension polymerization. Equilibrium and kinetics experiments were then performed to verify the adsorption capacities of the resins for molecules of various sizes. The adsorption of small molecules reached equilibrium more quickly than the adsorption of large molecules. Furthermore, the resins with small pores are easy to lower their adsorption capacities for large molecules because of the pore blockage effect. After amination, the specific surface areas of the resins decreased. The average pore diameter decreased when the resin was modified with either primary or tertiary amines, but the pore diameter increased when the resin was modified with secondary amines. The phenol adsorption capacities of the amine-modified resins were reduced because of the decreased specific area. The amine-modified resins could more efficiently adsorb reactive brilliant blue 4 owing to the presence of polar functional groups.