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1.
吸附法回收柠檬酸   总被引:6,自引:0,他引:6  
用静态吸附法测定了四种大孔吸附树脂对柠檬酸的最大吸附量,用间歇法测定了不同温度下的吸附等温线,并筛选出一种最适宜的树脂进行了动态测试。用固定床吸附模型模拟了吸附动态过程。计算值与实验值基本符合。  相似文献   

2.
以芦丁为吸附质,考察不同种类的大孔吸附树脂对芦丁水溶液的吸附、树脂活化处理方法、吸附实验的实施方法和树脂的最佳用量。结果表明,最佳操作条件如下:树脂活化时间5 d,吸附前用95%乙醇浸泡会明显增加吸附量,吸附实验增重物确定为玻璃珠子,树脂适宜用量约为1.20000 g。并做了6种大孔树脂在芦丁水溶液中的吸附等温线,得出大孔树脂在芦丁中的吸附,会发生毛细下降效应,通过对大孔树脂的物化参数分析,发现大孔树脂的比表面积并不是决定吸附量的最主要因素,而由大孔树脂的物化参数以及溶剂的性质等协同作用决定。  相似文献   

3.
宣寒  赵林 《安徽化工》2007,33(5):30-31
对中药黄芩提取液中的黄芩苷在AB-8大孔吸附树脂上的吸附性能进行静态吸附研究.研究结果表明,在实验条件下吸附等温线符合Langmuir吸附等温方程式,吸附平衡时间约为2 h.得出结论,AB-8大孔吸附树脂对黄芩苷有较好的吸附分离性能.  相似文献   

4.
大孔吸附树脂吸附乳酸及乳酸与谷氨酸的分离   总被引:1,自引:0,他引:1  
通过筛选,得到大孔吸附树脂NKA-II,并用其对乳酸进行分离. 测定了该树脂对乳酸与谷氨酸的吸附选择系数,得到了乳酸在NKA-II上的吸附等温线,并对其吸附动力学和动态吸附进行了研究. 结果表明,NKA-II对乳酸和谷氨酸的吸附选择系数KGL=16.19. 该树脂对乳酸的吸附等温线符合Freundlich方程,在26和48℃下的相关系数R2均大于0.99,方程的特征参数n>1,属"优惠吸附". 吸附动力学研究表明,粒内扩散是吸附过程的主要控制步骤,符合Kannan-Sundaram粒内扩散模型,相关系数R2=0.9906,粒内扩散速率常数kp=6.0129 mg×min0.5/g. 动态吸附实验结果表明,乳酸的穿透体积比谷氨酸大110.6 mL,故该树脂可以成功地应用于乳酸与谷氨酸的分离.  相似文献   

5.
以大孔交联氯甲基化聚苯乙烯为原料通过Friedel-Crafts反应、甲胺化反应和乙酰化反应,制备了N-甲基乙酰胺基修饰的超高交联型吸附树脂。研究了树脂对水溶液中水杨酸的吸附去除性能。结果表明,所制得的树脂能有效吸附水溶液中的水杨酸,吸附等温线都是I型吸附等温线,Langmuir和Freundlich方程模型都可很好地拟合平衡吸附数据。水杨酸原始浓度在903.6 mg/L、流速在88 mL/h,10 mL湿树脂在60 BV(1BV=10 mL)左右出现穿透,性能优于目前商品化的XAD-4树脂和XAD-7树脂。  相似文献   

6.
通过后交联反应,用乙酰苯胺修饰氯甲基化的低交联大孔聚苯乙烯-二乙烯(氯球),合成了一种超高交联吸附树脂ZH-05。用活性炭GAC和Amberlite XAD-4树脂作为参照,测试了ZH-05吸附树脂对2,4-二氯苯酚的吸附性能。讨论了静态平衡吸附行为和化学吸附特征的证实。结果表明:吸附等温线都能用Langmu ir方程很好的拟合,且2,4-二氯苯酚在ZH-05吸附树脂上的吸附是一个吸热过程,吸附量随吸附温度的升高而增加,和活性炭一样,ZH-05树脂对水溶液中2,4-二氯苯酚的吸附过程中同时存在着物理吸附和化学吸附。  相似文献   

7.
大孔树脂对甘油的静态吸附及其热力学研究   总被引:3,自引:0,他引:3  
研究了8种大孔树脂对甘油的静态吸附行为,根据吸附等温线研究了吸附热力学性质,在303~323 K和研究的浓度范围内,树脂HPD500对甘油的吸附平衡数据符合Freundlich吸附等温方程。实验结果表明,较大的比表面积和带有一定极性的树脂有利于吸附,吸附过程为放热的物理吸附,降低温度有利于吸附。并计算了甘油在大孔树脂HPD500上的吸附焓变、吉布斯自由能变、吸附熵变,并对吸附行为做了合理的解释。  相似文献   

8.
吸附热预测吸附等温线   总被引:1,自引:0,他引:1  
实验测定了N2 在沸石分子筛、C2 H6 在活性炭、CO2 在硅胶上的吸附等温线 ,研究用Clausius Clapeyron方程求得等量吸附热、再利用所得的吸附热预测其它温度的吸附等温线数据的方法。将吸附热预测的等温线与实验值及插值法内插得到的吸附等温线数据进行了比较 ,结果表明吸附热预测值与实验值吻合较好。此外还对文献数据利用等量吸附热预测较高压力 ( 65 0kPa)下的等温线 ,均与文献中的实验值一致。为吸附工业操作需要不同温度下的等温线数据和吸附过程的模拟与设计提供了简便、准确的计算方法  相似文献   

9.
张振  李丹  陈辰  吴菁岚  应汉杰  乔浩 《化工进展》2023,(8):4153-4158
采用一种新型的吸附树脂RH-1从唾液酸(sialic acid,SA)生物转化液中分离回收SA。研究了SA在树脂上的吸附平衡、吸附动力学以及柱动态吸附和解吸的过程。测定了不同温度条件下SA的吸附等温线,发现SA在树脂上的吸附容量随着温度升高而降低,吸附过程为放热过程,符合Henry吸附模型(R2=0.998)。表面扩散模型能较好地描述SA在树脂上的吸附动力学行为,拟合得到的表面扩散系数De为2.19×10-9m2/s,SA在10min内就可以达到吸附平衡。最后通过柱动态法回收转化液中的SA,考察了SA在不同工艺条件下在树脂上的穿透曲线,水作为洗脱剂,回收得到的SA收率≥99.8%。用水就能实现SA的分离回收,为SA的绿色生产提供了一种新方法。  相似文献   

10.
在静态条件下,研究了水溶液中新型树脂ZH-03吸附苯酚和2,4-二氯苯酚的热力学特性,测定了在288k、303k、318k和下降到288k温度下的吸附等温线。结果表明,在稀溶液中ZH-03吸附剂对苯酚和2,4-二氯苯酚的吸附同时符合Langm u ir和F reund lich模型。该树脂对苯酚的吸附是一个放热过程,而对2,4-二氯苯酚的吸附属于吸热过程,同时不同温度下的吸附等温线和热力学计算结果都证明了在树脂ZH-03对2,4-二氯苯酚吸附行为中存在着化学吸附。  相似文献   

11.
In this study, epichlorohydrin cross-linked chitosan beads were used for the removal of Reactive Black 5 (RB 5) from aqueous solution. The adsorption of RB 5 onto the cross-linked chitosan beads was strongly pH dependent. The adsorption capacity of RB 5 onto the cross-linked chitosan beads increased with increasing temperature, indicating the endothermic nature of the adsorption process. The thermodynamic parameters, namely the Gibbs free energy, enthalpy and entropy of the RB 5 adsorption process were calculated. The kinetic parameters were measured in a batch adsorber to analyze the rate of adsorption of RB 5 onto the cross-linked chitosan beads.  相似文献   

12.
The adsorption of vinyl sulfone type reactive black 5 (RB 5) in aqueous solution onto chitosan beads and cross-linked chitosan beads with glutaraldehyde has been investigated in terms of initial pH and temperature of the solution. The adsorption equilibrium data were correlated with three adsorption models, such as Langmuir, Freundlich and Sips isotherms. Among them, the Freundlich isotherm best fit the data over the entire pH and temperature range of the solution. The adsorption capacity of RB 5 onto chitosan beads and cross-linked chitosan beads increased with decreasing initial pH and with increasing temperature. Equilibrium amount of RB 5 on chitosan beads was greater than that of cross-linked chitosan beads at the same initial pH values. Thermodynamic studies have also been carried out and values of standard free energy (°Gℴ), enthalpy (°Hℴ) and entropy (°Sℴ) were calculated.  相似文献   

13.
《分离科学与技术》2012,47(9):1391-1401
The main objective of this study is to investigate the possibility of crosslinked chitosan-tetraethoxy orthosilane (TEOS) (chitosan-silica) beads to be used as an adsorbent material to adsorb the lignosulfonate compound in solution. Different parameters affecting the adsorption capacity such as contact time, adsorbent dosage, initial concentration, pH, ionic strength, and temperature have been investigated. Adsorption isotherms of lignosulfonates onto chitosan-silica beads were also studied. Batch adsorption experiments were carried out and the optimum lignosulfonate adsorption onto chitosan-silica beads occurred at contact time of 30 minutes, the adsorbent dosage of 40 g/L, initial concentration of 50 mg/L, pH 5, and a temperature of 45°C. Adsorption isotherms studied through the use of graphical methods revealed that the adsorption of lignosulfonates onto chitosan-silica beads follows the Langmuir model, with the maximum adsorption capacity being 238.3 mg/g at pH 7. Adsorption is dependent on the ionic strength. The adsorption of lignosulfonate on chitosan-silica beads was best described with the pseudo-second-order kinetic model with a rate constant of 0.32 g · mg?1 · min?1, while intra-particle-diffusion was the main rate-determining step in the lignosulfonate adsorption process. The chitosan-silica beads investigated in this study were thus exhibited as a high potential adsorbent for the removal of lignosulfonate from solution.  相似文献   

14.
《分离科学与技术》2012,47(7):1132-1139
A new humic acid (HA) based adsorbent was prepared by coating humic acid on chitosan tripolyphosphate (CTPP) beads. Humic acid-chitosan tripolyphosphate (HA-CTPP) beads thus obtained were characterized using Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Swelling capacity studies of CTPP and HA-CTPP beads conducted in the pH range, pH = 1–10 showed that HA-CTPP beads are more stable against swelling than CTPP beads. Equilibration of HA-CTPP beads in water for different pH showed that leaching of HA from the beads is negligible and the beads are stable for adsorption applications. Adsorption of Pb(II) ions onto HA-CTPP beads were studied as a function of various operational parameters such as initial pH, metal ion concentration, and contact time. The results showed that HA-CTPP beads are suitable for Pb(II) ions adsorption and the kinetics of sorption very well fit into pseudo-second order model. The Langmuir model was found to be more suitable for explaining the observed adsorption data, giving a theoretical maximum adsorption capacity of 223.7 mg/g. HA-CTPP beads could possibly find application in the treatment of waste water contaminated with other toxic and/or heavy metals.  相似文献   

15.
Magnetic beads were prepared from glycidyl methacrylate (GMA), and ethyleneglycol dimethylmethacrylate (EGDMA) in the presence of Fe3O4 nano‐powder via suspension polymerization. The magnetic beads were characterized by surface area measurement, electron spin resonance (ESR), and scanning electron microscopy (SEM). ESR data revealed that the beads were highly super‐paramagnetic. The effects of contact time, pH, ionic strength, and temperature on the adsorption process have been studied. Adsorption equilibrium was established in about 120 min. The maximum adsorption of trypsin on the magnetic beads was obtained as 84.96 mg g?1 at around pH 7.0. At increased ionic strength, the contribution of the electrostatic component to the overall binding decreased, and so the adsorption capacity. The experimental equilibrium data obtained trypsin adsorption onto magnetic beads fitted well to the Langmuir isotherm model. The result of kinetic analyzed for trypsin adsorption onto magnetic ion‐exchange beads showed that the second order rate equation was favorable. It was observed that after six adsorption–elution cycle, magnetic beads can be used without significant loss in trypsin adsorption capacity. Finally, the magnetic beads were used for separation of bovine serum albumin (BSA) and trypsin from binary solution in a batch system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

16.
以壳聚糖(CTS)为基材、硝酸银为印迹物,提出了一种新的CTS水凝胶球的制备方法.采用Ag+吸附容量作为评价指标,对凝胶球的制备条件进行了优化,并进行了吸附试验.结果显示,当CTS用量为质量分数2.5%、交联剂用量为体积分数3.0%、凝固浴三乙醇胺的质量分数为10.0%、制备温度为25℃,热处理温度为60℃,洗脱剂硫代...  相似文献   

17.
利用反相悬浮结合溶剂结晶致孔法制备了具有超大孔隙、球形度良好的聚丙烯酰胺晶胶微球,晶胶微球平均粒径为234.1 mm,孔径约为10~50 mm。采用原位接枝法,将2-丙烯酰胺基-2-甲基-1-丙烷磺酸(AMPSA)接枝到晶胶微球孔隙表面上,得到了带有磺酸基团的阳离子交换晶胶微球。考察了晶胶微球的生物相容性和吸附蛋白质及重金属离子Cu2+的性能,结果表明:在大肠杆菌培养液中,添加晶胶微球,对大肠杆菌的生长影响不大。接枝了AMPSA的晶胶微球表现出更强的吸附Cu2+的能力,吸附容量达到1.14 mmol·g-1。同时,接枝后的晶胶微球也具有一定吸附蛋白质的能力,溶菌酶的吸附容量达到54.5 mg·g-1。因此,该大孔晶胶可望在微生物固定化、生物分离和重金属离子吸附中会发挥更大的作用。  相似文献   

18.
The study aims to develop gel beads with improved functional properties and biocompatibility from hogweed (HS) pectin. HS4 and AP4 gel beads were prepared from the HS pectin and apple pectin (AP) using gelling with calcium ions. HS4 and AP4 gel beads swelled in PBS in dependence on pH. The swelling degree of HS4 and AP4 gel beads was 191 and 136%, respectively, in PBS at pH 7.4. The hardness of HS4 and AP4 gel beads reduced 8.2 and 60 times, respectively, compared with the initial value after 24 h incubation. Both pectin gel beads swelled less in Hanks’ solution than in PBS and swelled less in Hanks’ solution containing peritoneal macrophages than in cell-free Hanks’ solution. Serum protein adsorption by HS4 and AP4 gel beads was 118 ± 44 and 196 ± 68 μg/cm2 after 24 h of incubation. Both pectin gel beads demonstrated low rates of hemolysis and complement activation. However, HS4 gel beads inhibited the LPS-stimulated secretion of TNF-α and the expression of TLR4 and NF-κB by macrophages, whereas AP4 gel beads stimulated the inflammatory response of macrophages. HS4 gel beads adsorbed 1.3 times more LPS and adhered to 1.6 times more macrophages than AP4 gel beads. Thus, HS pectin gel has advantages over AP gel concerning swelling behavior, protein adsorption, and biocompatibility.  相似文献   

19.
In this study Ni2+ adsorption properties of polyethyleneimine (PEI)‐attached poly(p‐chloromethylstyrene) (PCMS) beads were investigated. Spherical beads with an average size of 186 μm were obtained by the suspension polymerization of p‐chloromethylstyrene conducted in an aqueous dispersion medium. Owing to the reasonably rough character of the bead surface, PCMS beads had a specific surface area of 14.1 m2/g. PEI chains could be covalently attached onto the PCMS beads with equilibrium binding capacities up to 208 mg PEI/g beads, via a direct chemical reaction between the amine and chloro‐methyl groups. After PEI adsorption with 10% (w/w) initial PEI concentration, free amino content of PEI‐attached PCMS beads was determined as 0.91 mEq/g. PEI‐attached PCMS beads were utilized as adsorbents in the adsorption/desorption of Ni2+ ions from synthetic solutions. The adsorption process was fast; 90% of adsorption occurred within 90 min, and equilibrium was reached at around 2 h. Adsorption capacity was obtained to be 78.2 mg/g at a pH of about 6.0. The chelating beads can be easily regenerated by 0.1 M HNO3 with higher effectiveness. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2467–2473, 2002  相似文献   

20.
多孔聚合物载体的制备及吸附脱除二苯并噻吩的初步探索   总被引:7,自引:0,他引:7  
制备了一种多孔的聚合物吸附载体,并考察了在汽油模拟体系进行深度脱硫的效果. 载体的多孔性质有利于提高脱硫的吸附容量和选择性. 在正辛烷与二苯并噻吩组成的模拟体系中,DBT的初始浓度为1.26 g/L,吸附载体用量为50 g/L,测得吸附载体的吸附量为16 mg/g,脱硫率达到88%.  相似文献   

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