球形纤维素基磁性阳离子的化学转化制备及机理研究

通过正交设计实验确定了用化学转化法制备球形纤维素基磁性阳离子交换树脂的最佳条件,即:将树脂在室温下浸渍于摩尔比为1∶2的Fe3 与Fe2 混合铁盐溶液中90min,然后,加入2mol/L的NaOH溶液,在搅拌下转化20min,Fe3 、Fe2 将转化为FeFe2O4并将均匀的分布在树脂的表面及大孔结构中,从而获取磁性树脂.并初步探讨了阳离子交换树脂磁化的机理.     

磁性阳离子交换树脂的结构与性能分析

利用古埃磁天平法、扫描电镜、粉末Ｘ射线衍射以及分光光度法等检测了化学转化法制备的磁性阳离子交换树脂。结果表明,所制备的树脂内部磁性物质为Ｆｅ３Ｏ４,且在 树脂内部的孔道及表面分布均匀,均被封锁在树脂内部,因而,这类磁性树脂在碱性和中性盐溶液中具有较高的稳定性。此外,树脂的磁化过程并不影响其交换容量。     

环氧基磁性离子交换树脂的合成与表征

用r—三氧化二铁—二乙烯三胺—双酚A环氧树脂首次合成了环氧基磁性离子交换树脂。实验结果表明,磁性树脂微球尺寸和吸附容量决定于树脂制备过程中的各种因素。一批典型的环氧基磁性树脂平均直径为0.15mm、吸附容量为3.3meq/g—R,磁化率为8.2emu/g—R,在酸性或碱性介质中稳定。实验数据也证实了这是一类优良的螯合树脂,对Zn~(2+)、Cd~(2+)、Hg~(2+)、Co~(2+)、Ni~(2+)、Pb~(2+)和其他二价阳离子有适当的螯合能力。但不吸附碱土金属离子,这和聚多胺树脂相同。     

聚苯乙烯磁性树脂的合成及性能

用悬浮聚合法,将γ—Fe_2O_3加入苯乙烯和二乙烯苯(DVB)中可制得聚苯乙烯磁性树脂。本文详细研究了各种因素对合成的影响。实验制得一批典型树脂的磁粉含量为12.8％,粒度为80目。磺化后得到磺酸型阳离子交换树脂,其交换容量为3.22mmol/g—R。实验表明,该种磁性树脂有一定的磁化性能,且耐碱性较好。     

脱色树脂性能研究

本文合成了对色素具有高只附容量，强选择性的大孔阴离子交换树脂，详细讨论了影响树脂脱色性能的各种因素。结果表明：树脂的孔结构，功能基结构对其脱色性能有很大影响，并在此基础上进行了一些理论分析。     

D315大孔阴离子交换树脂对Au(Ⅲ)的吸附性能研究

研究了D315大孔阴离子交换树脂从酸性含金氯化溶液中吸附金的性能,考察了吸附时间,pH值,温度,阴离子浓度等因素对树脂吸附金的影响.结果表明,在pH=2时树脂的吸附效果最佳,静态饱和吸附容量可达到228.80mg/g(Au/干树脂),温度越高越有利于吸附,吸附反应热焓△H=11.30kJ/mol.吸附平衡服从Freundish吸附等温式.用8%硫脲-1mol/L硫酸可以将树脂上的金完全解析.     

化学转化法制备磁性阳离子交换树脂的研究

本文通过化学转化法即化学共沉淀法，分别研究了强酸性和弱酸性阳离子交换树脂的磁转化对相应所得树脂的磁性的影响，制得了磁性毫米级和微米级粒径的强酸性，弱酸性阳离子交换树脂。所得磁性树脂有磁性强，磁性物质分布均匀而且稳定，并保持树脂的原有特性。     

高交换容量苯乙烯大孔强碱Ⅰ型阴离子交换树脂的合成

本工作合成的高交换容量苯乙烯大孔强碱1型阴离子交换树脂80A,理化性能接近于Amberlite IRA900C的水平。80A的重量交换量为4.0～4.4meq/g(干树脂),比表面积为40～50m~2/g,平均孔径为90～100。80A的中间体,是苯乙烯—二乙烯苯共聚物(白球)及其氯甲基化产物(氯球)。白球交联度为6～10,以汽油、液体石腊为混合致孔剂。氯甲基化反应,采用无水三氯化铝为催化剂,反应温度35～40℃,反应时间约8小时,氯球的氯含量高达20～23％。     

α-甲基丙烯酸甲酯-二乙烯苯共聚体碱性水解反应的研究

本文合成3α-甲基丙烯酸甲酯-二乙烯苯大孔共聚体(MMA-DVB),研完了诸因素对碱性水解反应的影响.结果表明,以10—100％糖醇为溶胀剂,以60％ NaOH热水溶液为水解剂,在150℃反应4—10小时,酯基水解率可达90—95％。制得的弱酸离子交换树脂,其交换容量为9meq/g。树脂机械强度良好。     

反应温度对弱碱树脂交换容量的影响

本文探讨了用二甲胺胺化的大孔弱碱性阴离子交换树脂，在胺化过程中，不同的反应温度对树脂强碱基因含量及全交换容量的影响．     

Preparation of magnetic anion exchange resin and their adsorption kinetic behavior of reactive blue

Magnetic anion exchange resin(MD-1) was prepared from quaternization of magnetic copolymeric resin(glycidyl methacrylate -eo-divinylbenzene).For comparison,magnetic resin MD-0 without quaternization and non-magnetic resin(D-1) were also synthesized for the adsorption process.It was found that the adsorption was mainly contributed to the chemical interaction between quaternary ammonium groups and reactive blue RXHC.Due to the smaller size,MD-1 had faster adsorption and desorption kinetics than D-1.Coupled with the advantage of easy separation,the magnetic anion exchange resin was considered to be superior to common anion exchange resin in removal of reactive dye.     

Preparation and application of a novel magnetic anion exchange resin for selective nitrate removal

正A novel magnetic anion exchange resin NDM-1 was prepared through suspension polymerization and then functionalized with ammonolysis and alkylating agents.Its application for selective removal of nitrate was performed in comparison with MIEX~.The results demonstrated that NDM-1 achieved higher efficiency in nitrate removal than MIEX~ did,with or without the existence of competing anion SO_4~(2-) ascribed to its longer alkyl chains on exchange sites.Combined with the advantage of easy separation due toγ-Fe_2O_3 implanted,the magnetic anion exchange resin NDM-1 was considered to be superior to MIEX~ for nitrate removal in practical application.     

丙烯酸在强碱阴离子交换树脂中的聚合

研究了以水为介质，丙烯酸在强碱阴离子交换树脂中聚合时羧基分配系数随浸泡时间和反应时间的变化，以及树脂残阴交换量随反应时间的变化，结果是羧基分配系数在浸泡一小时后达到平衡，聚合反应开始后分配系数又迅速增大，三小时后达到最大值。残阴交换量随反应进行而减小，三小时后达到最小值。经分析认为丙烯酸的主要聚合场所是在树脂相，聚合过程中单体不断向树脂相扩散，基本不在液相聚合。     

以交联聚乙烯醇为载体的阴离子交换剂的合成与性能研究

大孔乙酸乙烯酯－异氰尿酸三烯丙酯共聚物树脂经醇解生成亲水性的交联聚乙烯醇，然后相继与环氧氯丙烷和二乙胺反应，合成出含二乙基氨基羟丙基的阴离子交换剂，研究了交联聚乙烯醇环氧基化的最佳条件，发现以二甲基亚砜作溶剂能够显著地提高活化程度，反应时间以３ｈ为最佳，并研究了该阴离子交换剂的交换量、亲水性、热稳定性、溶胀稳定性，发现它具备常压分离蛋白质所需的基本性能，是较为理想的生化用的离子交换剂。     

牛磺酸和甘氨酸在D290树脂上的离子交换平衡

研究了牛磺酸与甘氨酸在阴离子树脂D290上的离子交换平衡.采用静态法分别进行牛磺酸/氢氧根/D290树脂和甘氨酸/氢氧根/D290树脂体系的离子交换平衡实验并测定等温线;在不同的离子强度下进行了牛磺酸/甘氨酸/氢氧根/D290阴离子交换树脂体系的离子交换平衡实验,测定牛磺酸和甘氨酸在碱性条件下的竞争交换平衡等温线.实验结果表明,牛磺酸在D290阴离子交换树脂上的交换量大于甘氨酸的交换量,阴离子交换树脂对牛磺酸和甘氨酸的选择性系数分别为STau-,OH-=2.55,SGly-,OH-=1.65.在牛磺酸/甘氨酸/氢氧根/D290树脂体系中,D290树脂对牛磺酸/甘氨酸/氢氧根3种离子的选择性从高到底顺序是:牛磺酸＞甘氨酸＞氢氧根.树脂对牛磺酸的选择性要大于对甘氨酸的选择性.随着溶液中离子强度的增大,树脂对牛磺酸与甘氨酸之间的选择性下降.     

RECOVERY OF URANIURN FROM CARBONATE SOLUTIONS USING STRONGLY BASIC ANION EXCHANGER 3．THE MECHANISMS OF RECOVERY PROCESSES

A moving boundary model under considering the volume change of spherical resin beads during ion exchange processes was employed to recognize the mechanisms of reecovering uranium from carbonate solutions using strongly basic anion exchanger.Two important factors,swelling and ion exchange,which directly affect the violume of ion exchangers were taken into account.An ion exchange mechanism has been found for the forward reaction PCl/[UO2(CO3)3]^4-,and is partical diffusion governing at high concentration of the complex anion.The mechanism of RCl/U(VI) at pH 5.5-7.5 is a chemical reaction taking place at the moving boundary of the unreacted nucleus.For the reverse reaction RnU/NaCl,the uranyl tricarbonate complex anion in the resin phase is replaced by Cl^- ions with an ion exchange mechanism alway determined by particle diffusion.The other forms of uranium in the solid phase loaded on the resin at pH5.5-7.5 should belong to non-exchangeable uranium.The mechanism of the reverse reaction RnU/HCl is always chemical reaction which is not restricted to the moving boundary of the unreacted core.     

弱碱性和强碱性阴离子交换树脂的离子交换平衡的比较SO2-4-Cl——NO-3体系

本文详细地比较了在弱碱性和强碱性阴离子交换树脂上, SO_4~(2-)-Cl~-、NO_3~--Cl~-及NO_3~--SO_4~(2-)二元交换的等温线和修正选择系数。实验测定及理论计算了上述三种二元交换反应的标准自由能的改变量。测得了在弱碱性树脂上的SO_4~(2-)-Cl~--NO_3~-三元交换的等温线。适用于强酸性和强碱性树脂的从二元交换平衡数据推算三元交换平衡数据的方法推广应用于弱碱性树脂。     

D301 resin as a solid base for phosphine-free Heck reactions with heteroaryl halides

A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality（Grade Matrix Structure：Styrene-DVB D301R）,used as base to Heck reactions catalyzed by palladium reagent without phosphine compound as ligand is described.It was found that the D301 resin used as base is an efficient and reusable base and can be regenerated and recycled in the reaction.The olefmation of heteroaryl halides prepared the corresponding products in good yields using D301 resin as base.