离子交换树脂在明胶稀胶液纯化过程中的应用

<正> 在骨明胶的生产中,透过率的高低、色泽的深浅、灰分的高低、离子杂质的多少,都受明胶纯度的影响。为提高明胶的纯度,一般在淡胶液中要有去除颗粒性及有机杂质的净化处理,而许多厂家只用一种粗处理——用过滤棉为介质的板框压滤,除去悬浮于淡胶液中粗糙的大颗粒杂质及部分中等颗粒的杂质,细微颗     

聚氯乙烯树脂稀溶液粘数测定中的注意事项

介绍了聚氯乙烯树脂稀溶液粘数测定中的注意事项，分析了各种操作对结果产生的影响并进行了原因分析。     

测试条件对聚氯乙烯树脂稀溶液粘数的影响

聚氯乙烯树脂稀溶液粘数是聚氯乙烯树脂的一项重要指标,它的高低决定着产品的不同用途。本实验测试了几种不同测试条件如测试温度、黏度计毛细管直径、溶剂浓度等对聚氯乙烯树脂稀溶液粘数结果所产生的影响,通过实验数据的理论分析和计算,对原因进行了具体的分析。这些分析结果的获得对提高粘数分析的准确性,对于指导实际生产,规范检验操作,修订检验标准都有着重要的意义。     

离子交换树脂对咖啡因溶液提浓性能的研究

选用不同型号阳离子交换树脂和洗脱剂,对1%咖啡因溶液交换、洗脱过程进行研究。结果表明:相比于724、D-113、D-151树脂,732树脂交换处理量达10BV,洗脱速度快,单次洗脱浓度可达3.82%;80℃水更适合作为洗脱剂;经过3次叠加交换、洗脱后,1%咖啡因溶液提浓到7.39%,可为工业生产中结晶母液回收咖啡因过程提供参考。     

离子交换法分离钨酸盐溶液中的钼(VI)新工艺

提出了一种新的钨钼深度分离方法。讨论了脂型号、硫化条件和再生条件对树脂法分离钨钼效果及树脂使用性能的影响。运用正交试验得到了较佳的树脂交换－－再生操作条件。     

离子交换树脂 四

③巨孔度(maclopolality)——巨孔度或称微小球间的多孔度离子交换树脂的基础母体,由微小球的凝集所形成1个球状粒子时,由微小球粒子的集块生成的空间容积。也有称为巨孔,意味着真的多孔性。 MR形(巨孔形)的离子交换树脂是具有上述的3种类的多孔度。MR形的离子交换树脂的物理及化学的各种性质是极好的。 又MR形离子交换树脂若与同样的水分保有能力的凝胶形离子交换树脂相比较,物理强度大。其理由是MR形离子交换树脂在离子交换时生成的粒子内部的压力可由细孔所吸附,凝胶形离子交换树脂中是没有这样     

Removal of Mercury (II) from Aqueous Solution using Chitosan-graft-Polyacrylamide Semi-IPN Hydrogels

Chitosan-graft-polyacrylamide semi-interpenetrating polymer network (IPN) superabsorbent hydrogel was prepared via UV irradiation and N, N′-methylene-bis-acrylamide was used as crosslinker. The product was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The hydrogels were observed to exhibit as much as 2580.2% swelling under optimum reaction conditions. The hydrogel is an efficient selective sorbent for the removal of mercuric ions (Hg(II)) from aqueous solutions. The mercury sorption capacity under non-buffered conditions is achieved around 9.98 mmol · g^?1 (or 2001.8 mg (mercury)/g (hydrogel)) via the colorimetric method. The kinetic data were fitted to the pseudo second order model. Furthermore, the influence of pH, hydrogel dose, and initial mercury concentration on adsorption capacity of the semi-IPN hydrogel was evaluated. Also, the isothermal adsorption equilibrium data was described using the Langmuir model. Finally, the mercury loaded hydrogel was regenerated without losing its original activity and stability.     

以蔗糖飞灰吸附剂分离废水中的β-萘磺酸

Bagasse fly ash was converted into an inexpensive adsorbent and utilized for the removal of β-naphthalenesulfonic acid in dilute solution. The effect of pH, temperature, adsorbent concentration, and co-existed acids on the removal ofβ-naphthalenesulfonic acid was examined. The adsorption data have been correlated with both Langmuir and Freundlich adsorption models. Thermodynamic parameters obtained indicate the feasibility of the process, and kinetic studies provided the necessary mechanistic information of the removal process.     

改性坡缕石黏土对水中木质素磺酸钠吸附研究

用盐酸和焙烧处理的方法对坡缕石黏土进行了改性,制备了酸处理坡缕石黏土和热处理坡缕石黏土,用XRD和TEM对不同方法处理的坡缕石黏土进行了结构和形貌表征,并使用黏土对木质素磺酸盐废水进行了吸附研究。结果表明,在盐酸浓度为1.0 mol/L,60～70℃,改性处理6 h条件下制得的吸附剂相对于原土及热处理的坡缕石黏土吸附效果最好,动力学研究表明吸附过程符合准二级动力学模型,吸附等温线符合Langmuir吸附模型,其平衡吸附量可达到343.99 mg/g。实验证明该吸附过程是一个放热过程。     

Investigation of Selectivity and Kinetic Behavior of Strong‐Base Ion Exchange Resin Purolite A 520E for Nitrate Removal from Aqueous Solution

Abstract

The aim of this work is to present experimental results on the removal of nitrate by nitrate selective ion exchange resin, Purolite A 520E. The resin particle size, nitrate concentration, temperature, and stirring speed were investigated as experimental parameters and the optimum conditions for nitrate removal were determined. Nitrate removal by strong base anion exchange resin Purolite A 520E was carried out with the batch method in the presence of chloride and sulfate ions. The existence of a high concentration of competing ions in a solution resulted in a reduction of nitrate removal. Nitrate removal ratios decreased from 98% to 85% and 88%, respectively, in the presence of chloride and sulfate ions when the chloride and sulfate ratios were increased in solution. The process kinetics were predicted by using Homogenous Diffusion Models. It was seen that about 98% of nitrate in the aqueous solution could be removed using optimum conditions.     

Removal of Chlorophenols from Aqueous Solution by Anion-Exchange Resins

Abstract

The effects of pH value and chloride ion concentration on the removal of chlorophenols from aqueous solutions by Purolite A-510 resin [macroreticular polystyrene-divinylbenzene resin with R(CH₃)₂(C₂H₄OH)N⁺ group] are discussed by the species distributions of chlorophenols. Those chlorophenols include phenol, 2-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. The investigations showed that the chlorophenols could be removed effectively at alkaline conditions where the ion-exchange reaction was dominant. Also, the removal of chlorophenols increased with the number of chlorine atoms on the chlorophenols. The removal of chlorophenols via the ion-exchange reaction was hindered by the presence of chloride ions. The effect of chloride ions, however, was diminished in acidic solutions where the adsorption reaction was dominant. The proposed equilibrium model, which considers both adsorption and ion-exchange reactions, adequately describes the sorption behavior of chlorophenols. The partition constants of the protonated chlorophenols can be estimated from the octanol/water partition coefficients of the phenolic compounds.     

粉煤灰碱熔-水热合成沸石用于水溶液中汞的吸附

汞被认为是危害最为严重的重金属之一。目前虽已有大量水处理技术可用于水中汞的去除,但由于成本较高等原因均未实现大面积的工业化应用。以工业固废粉煤灰为原料通过碱熔-水热法合成了沸石,可将其应用于水溶液中汞的吸附。结果表明:碱熔活化可以使得粉煤灰中稳定的莫来石、石英及非晶相矿物转变为钠铝硅酸盐、硅酸钠和钠霞石等矿物;这些矿物可溶于氢氧化钠溶液中,形成富含钠、铝、硅的碱性溶液;在适宜的水热条件下,通过调配铝硅比,可合成纯度较高的NaA型沸石;该法合成的粉煤灰基沸石可有效吸附水溶液中的Hg(II),去除率可达95%左右,吸附过程符合拟二级吸附动力学模型,反应速率同时受到内外扩散影响。     

Phosphate Removal from Aqueous Solution Using Coir-Pith Activated Carbon

The present study deals with the removal of phosphates from aqueous solution using activated carbon developed from coir pith. Batch adsorption experiments were performed to delineate the effect of initial pH, contact time, adsorbent dose and temperature on the removal of phosphates by coir-pith activated carbon (CAC) (activated by H₂SO₄). The removal was found to be maximum in the pH range of 6–10. The kinetics of adsorption showed that the phosphate adsorption onto CAC was a gradual process with a quasi-equilibrium being attained in 3 h. The adsorption equilibrium data followed the Temkin isotherm. Thermodynamic parameters such as ΔG ^o , ΔH ^o , and ΔS ^o were evaluated by applying the Arrhenius and van't Hoff equations, and it was found that the adsorption of phosphate on CAC was spontaneous and endothermic.