电位法研究D354树脂吸附苯甲酸的行为

利用电位法跟踪观察了在不同介质环境下,D354树脂吸附苯甲酸的行为。利用固-液界面吸附的动力学方程,求取表观吸附速率常数(k)。实验结果表明,D354树脂吸附苯甲酸的速率随外加盐浓度的增大而增大;在外加盐浓度不变的情况下,D354树脂吸附苯甲酸的速率随苯甲酸浓度的增大而减小。     

大孔树脂对喹乐霉素的静态吸附

考察了9种不同极性的大孔树脂对喹乐霉素的静态吸附解吸效果,探讨了吸附过程中树脂静态吸附动力学和25℃时的等温吸附过程,并用Langmuir与Freundlich方程分别对吸附过程进行了拟合。结果表明,XAD-16和D101树脂对喹乐霉素的吸附解吸效果较好,比较两种树脂等温吸附的Langmuir和Freundlich参数,D101树脂对喹乐霉素的吸附解吸作用最好,吸附量最大,达到0.976 mg/g干树脂,吸附过程更易发生。因此,D101树脂更适用于从标桩菌WXNXJ-B发酵液中吸附并解吸喹乐霉素。     

大孔吸附树脂纯化草木樨香豆素的动力学和热力学

通过静态吸附和解吸实验筛选出纯化草木樨香豆素的大孔吸附树脂,确定了HPD300树脂纯化香豆素的吸附动力学模型、等温吸附模型和热力学参数,并通过动态吸附和解吸实验优化其工艺条件。结果表明:HPD300树脂对香豆素的吸附量大、解吸率高、吸附速度快,其吸附动力学可用拟二级动力学方程很好地描述,等温吸附过程可用Langmu ir方程较好地拟合,其吸附是一个自发、放热的物理吸附过程,在优化的条件下产物中香豆素的纯度大于90%,回收率高于90%。研究表明:HPD300树脂是一种分离纯化草木樨香豆素的理想树脂,可用于大规模分离纯化草木樨香豆素。     

多孔树脂及碳纳米管对环丙沙星的吸附行为与机理

以环丙沙星为研究对象,研究了多孔树脂(超高交联树脂MN-202,氨基修饰树脂MN-150,大孔树脂XAD-4)和多壁羧基碳纳米管C-MWCNT对环丙沙星的吸附行为和机理。结果表明:吸附剂的吸附量随溶液pH值的升高呈先增加后减小的变化趋势。3种树脂的吸附能力随溶液离子强度的增强而提高,而碳纳米管则呈相反趋势,这是因为疏水作用和静电引力对两类吸附剂的贡献不同。环丙沙星在4种吸附剂上的吸附动力学都符合准二级动力学模型,吸附等温线符合Langmuir模型。升高温度可以增强MN-202和MN-150的吸附能力,可能是微孔填充受温度影响;温度对XAD-4吸附能力的负相关作用是由于疏水作用,是主要吸附机理。对于C-MWCNT,温度对它的影响很小,这是由于疏水作用、静电作用、π-π键和氢键的共同作用。     

大孔吸附树脂对葛根总黄酮吸附性能的研究

测定分析了AB-8等6种不同极性大孔吸附树脂对葛根总黄酮的吸附特性。静态实验结果表明,树脂的极性和空间结构是影响吸附效果的重要因素。AB-8树脂孔径适当,比表面积较高,葛根黄酮吸附量达74.3 mg/g。进行了静态吸附动力学的研究,并获得总黄酮吸附量与吸附时间之间的定量关系。动态吸附研究表明,在温度为20℃时,以吸附流速4 mL/min和洗脱流速3 mL/min较合适。而重复使用约10次以后,该树脂应进行再生。     

H103大孔吸附树脂分离纯化苦参碱与氧化苦参碱的研究

通过对比苦参总碱在九种大孔树脂上的静态吸附,筛选出对苦参总碱吸附能力较强的H103树脂;研究了H103树脂对上述两种生物碱的吸附等温曲线及吸附动力学行为;考察了苦参总碱在H103树脂上的动态吸脱附过程,用薄层色谱法(TLC)对洗脱液跟踪分析,用高效液相色谱法(HPLC)检测苦参碱、氧化苦参碱含量,确定了动态吸脱附的过程参数。结果表明,H103树脂对苦参总碱的等温吸附可采用Freundlich方程描述;由吸附动力学曲线得H103树脂在100 min内达到平衡,具有较快吸附速度,吸附动力学规律可用二级速率方程表示;动态吸脱附过程的洗脱条件为：用30%乙醇-25%氨水（115:1,v/v）,80%乙醇梯度洗脱,氧化苦参碱先被洗脱,苦参碱随后,两种生物碱可达到很好的分离,经计算苦参碱收率为90.1%,氧化苦参碱收率为85.3%。     

Mesoporous Calcium Phosphate Via Post-Treatment of α-TCP

α-Tricalcium phosphate (α-TCP) macroporous ceramic scaffold was chemically treated with a buffered solution at pH=4. Mesopores were formed in the scaffold after the treatment to result in a remarkable increase in surface area of the scaffold. The increase in the surface area is caused by precipitation of octacalcium phosphate (OCP). Bimodal pore size distribution consisting of mesopores and macropores obtained by the treatment of α-TCP scaffold having higher initial porosity brought about high adsorption of bovine serum albumin (BSA) than monomodal pore size distribution of mesopores. Adsorption of BSA, acidic protein, was suggested to result from crystallographic characters of OCP.     

红霉素在大孔树脂上的吸附动力学研究

采用液膜及孔内扩散模型,模拟不同温度和不同红霉素(EM)初始浓度条件下,大孔吸附树脂HZ816及XAD16吸附红霉素的动态吸附曲线,并获得液膜传质及孔内扩散系数;考察了温度及溶质浓度对红霉素在两种树脂中吸附动力学的影响.结果表明,在实验范围内,红霉素在HZ816和XAD16两种树脂上的吸附平衡数据满足Langmuir吸附等温线方程,液膜及孔内扩散模型能较好地描述红霉素在两种树脂上的吸附动力学,同时,模型拟合得到的液膜传质系数随着温度的升高而增大,随着初始浓度的增大而增大,孔内扩散系数随着温度的升高而增大,随着初始浓度的增大而减小.     

超高交联吸附树脂的合成及其对水杨酸的吸附性能

以甲苯、苯甲醇和氯甲醚为基本原料, 一锅法合成了极性超高交联吸附树脂HH-1;利用树脂HH-1上残留的大量未反应完全的氯甲基, 加入苯胺对树脂HH-1进行了后交联反应, 得到比表面积更大的超高交联吸附树脂HH-2。并对两种树脂进行了分析表征, 分析结果表明, 树脂HH-1和树脂HH-2的比表面积分别为67.85m²/g和555.22m²/g, 平均孔径分别为1.882nm和1.105nm。以亲水性小分子水杨酸作为吸附对象, 研究了两种树脂对水杨酸的吸附行为。结果表明, 交联后树脂HH-2对水杨酸的吸附能力是交联前树脂HH-1的5倍。主要原因是二次交联后, 树脂的比表面积得到了大幅度提高。     

ZH-01吸附树脂对苯甲酸的吸附性能研究

比较了超高交联吸附树脂ZH-01与大孔吸附树脂AmberliteXAD-4对苯甲酸的静态吸附和动态吸附行为,并探讨了温度和起始浓度对平衡时间和吸附速率的影响.从静态平衡吸附行为及其热力学性质讨论吸附机理,动态吸附进一步验证聚苯乙烯超高交联吸附树脂对苯甲酸的吸附能力比AmberliteXAD-4强.结果表明:在288～3...     

Effective adsorption of phenolic compounds by functional group modified resins: behavior and mechanism

A series of functional hyper-crosslinked resins were successfully synthesized by incorporating amino, hydroxyl, and complex functional groups into post-crosslinked polymer. Possessing high specific surface area and effective functional groups, the newly synthesized resins showed excellent adsorption capacity toward various phenolic compounds. HC-IT displayed huge advantage over the others. Its adsorption capacity for salicylic acid was up to 336 mg/g, which was 3.01–6.64 times higher than that of the commercial resins and 2.33 times higher than its non-functionalized precursor HCLR (144 mg/g). The improved adsorption capacity was attributed to its high specific surface area, good polarity, and proper pore structure.     

大孔吸附树脂对芦丁的吸附实验探索

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。     

Adsorption of benzoic acid and phenol from aqueous solution by activated carbons—effect of surface acidity

Effect of surface acidic groups of activated carbons on their adsorption characteristics for substrates from aqueous solutions were studied. Six kinds of carbons obtained commercially and their heat-treated products were used. Pore-size distribution, BET surface area and surface acidity were measured. Adsorption isotherms for benzoic acid and phenol from aqueous solutions (single or double components) were obtained. Substitution adsorption, i.e. substrate adsorbed preliminarily is substituted by another substrate, was also carried out. It was found that adsorption of benzoic acid is scarcely affected by surface acidity of carbons and the amount adsorbed is almost entirely controlled by the specific surface area of carbons. On the contrary, adsorption of phenol is retarded considerably by the acidity of carbons. In the case of solution of double components, benzoic acid is adsorbed predominatedly. The phenol adsorbed preliminarily is easily substituted by benzoic acid, but the substitution of benzoic acid by phenol scarcely proceeds.     

大孔树脂对金银花中绿原酸的纯化研究

考察不同型号的大孔吸附树脂对金银花中的绿原酸的提取纯化效果,为进一步开发金银花的相关产品提供参考。采用HPLC法测定绿原酸含量;选用5种不同型号的大孔树采用静态吸附法,筛选出吸附效果和解吸效果较好的大孔吸附树脂;采用动态吸附法,考察大孔树脂的吸附、解吸附性能和纯化效果。NKA-9大孔树脂综合性能最佳,提取液在酸性条件下吸附量最佳。NKA-9大孔树脂对绿原酸的提取纯化效果较好,可用于工业化生产。     

Comparative study of adsorption for m-phenylenediamine in aqueous solution onto chemically modified resins

Four kinds of hypercrosslinked resins (acidic resins labeled SAMR and TAMR and heterocyclic resins IDLMR and PRLMR) were synthesized as adsorbents to remove m-phenylenediamine (MPD) from aqueous solution comparably. The Brunauer–Emmett–Teller specific surface area and pore size distribution of the two types of resins have been compared, and the infrared spectra of the resins confirm the presence of the modified groups. The adsorption isotherms illustrate that the Freundlich equation fits more appropriately than the Langmuir equation or the Temkin equation. In addition, the kinetic curves indicate that the pseudo-second-order model is a better fit than the pseudo-first-order model. The thermodynamic studies show that the isosteric adsorption enthalpy changes (ΔH) and the Gibbs free energy change (ΔG) are both negative, revealing that all of the adsorption processes are spontaneous and exothermic. All of the modified resins exhibit the best adsorption capacity at pH = 6.24. The results show that the acidic resins have better adsorption of MPD. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47378.     

N-甲基乙酰胺基修饰的超高交联吸附树脂的合成与吸附性能

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。     

大孔吸附树脂富集款冬花总黄酮的研究

研究了大孔吸附树脂富集款冬花总黄酮的工艺。从5种大孔吸附树脂中筛选出AB-8型大孔吸附树脂适合富集款冬花总黄酮,并通过单因素实验确定适宜的富集工艺为:将4BV的款冬花样品液以3BV·h-1的速度上样,吸附40min,用4BV的纯化水以6BV·h-1的速度冲洗杂质,再用4BV的60%乙醇洗脱总黄酮。该树脂稳定性良好,可连续使用6次。     

碱性树脂吸附富马酸及富马酸与葡萄糖的分离

从6种碱性离子交换树脂中筛选得到强碱性树脂IRA-400,考察了该树脂在不同pH值、不同葡萄糖浓度下对富马酸和葡萄糖的吸附及富马酸在该树脂上的静态吸附等温线、吸附动力学及动态吸附与洗脱. 结果表明,在高葡萄糖浓度下,树脂IRA-400对富马酸的亲合力均大于对葡萄糖的亲合力;对富马酸的吸附等温线符合Freundlich方程,方程的特征参数n>1,属优惠吸附;不同pH值下的吸附动力学研究表明,液膜扩散是吸附过程的主要控制步骤,符合Boyd液膜扩散模型,液膜扩散速率常数k￠均小于0.15 min-1;动态实验结果表明,采用去离子水和1.0 mol/L NaOH交替洗脱树脂,可实现葡萄糖和富马酸的有效分离.     

大孔树脂对贯叶连翘中金丝桃素的静态吸附

考察了18种不同类型的大孔树脂对贯叶连翘中金丝桃素的静态吸附和解吸效果,并对3种效果较好的树脂进行了吸附动力学研究;比较了上样液pH对吸附效果的影响;探讨了NKA-9树脂在25℃等温吸附过程,并应用Langmuir方程进行了拟合。结果表明,弱极性树脂NKA-9对金丝桃素吸附解吸作用最好,到达吸附平衡时间为1h左右,吸附量可达12.45mg/g干树脂。上样液最佳pH=4,上样液pH对树脂的吸附有很大影响。NKA-9树脂对金丝桃素的吸附为单分子吸附,符合Langmuir吸附理论。     

两性官能团修饰的超高交联树脂的吸附性能

采用氨基苯酚修饰氯甲基化的聚苯乙烯-二乙烯苯合成了新型超高交联吸附树脂MAPR。通过红外、BET和TGA对树脂进行了表征,并通过静态吸附试验测定了MAPR树脂对邻甲苯胺、邻苯二甲酸、无水对氨基苯磺酸、间苯二酚、乙萘酚的吸附。结果表明:用氨基苯酚修饰的超高交联吸附树脂对碱性物质、酸性物质都具有一定的吸附性能,并对其进行了理论解释。