D113树脂对镁离子的交换特性

采用钠型大孔弱酸丙烯酸系阳离子交换树脂D113交换水中的镁离子.研究表明:D113树脂常温对镁离子的静态交换容量达到319.21 mmol/100g树脂;D113大孔树脂交换Mg2+的行为可用Freundlich和Langmuir等温式描述,但更符合Langmuir经验公式;测得热力学参数分别为:ΔHθ= 11.37 ...     

乙醇静态解吸D101C大孔吸附树脂对原人参二醇组皂苷分离提纯的影响

目的:分离提纯原人参二醇组皂苷(PPD),建立一种新的PPD皂苷的分离方法,为其分离提供理论依据.方法:本研究通过静态解吸试验,探索不同乙醇浓度对D101C大孔吸附树脂静态解吸PPD和PPT皂苷的影响,再结合丙酮沉淀法提纯PPD皂苷.结果:HPLC分析表明,将浓度为15 mg/mL的人参根总皂苷溶液用D101C大孔吸附树脂于室温下吸附12 h,再用35%乙醇溶液进行静态解吸,PPD和PPT皂苷的比值达到最大值,由解吸前的3.43提高到19.59.经80%乙醇溶液解吸后,用70%乙醇溶解,加入适量丙酮得PPD皂苷,其纯度由原料的61.32%提高到96.29%.结论:该方法操作简单,所得产品纯度高,是分离提纯PPD皂苷的简便而有效的方法.     

Adsorption and desorption properties of D318 resin for Cr（Ⅵ）

The adsorption capability of D318 resin for Cr(VI) was investigated by chemistry analysis. Experimental results show that D318 resin has the best adsorption ability for Cr(VI) at pH=3.16 in HAc-NaAc medium. The statically saturated adsorption capacity of the resin is 265.4 mg/g. The thermodynamic adsorption parameters, enthalpy change ΔH and free energy change ΔG ₂₉₈ of the adsorption reaction are 4.81 and −5.16 kJ/mol, respectively. The apparent activation energy E _a is 22.4 kJ/mol. The adsorption behavior obeys the Freundlich isotherm. The molar coordination ratio of the functional group of resin to Cr(VI) is 3:2. Cr(VI) adsorbed on D318 resin can be eluted by 5%NaOH-5%NaCl quantitatively. Foundation item: Project (Y304121) supported by the Natural Science Foundation of Zhejiang Province, China     

Synthesis of modified D401 chelating resin and its adsorption properties for Pb^2＋

A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb²⁺ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb²⁺ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb²⁺ concentration range of 200–400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb²⁺ increase by 77%–129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4–5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb²⁺ concentration range of 200–400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb²⁺ from its single-metal ion solution. Foundation item: Project(708049) supported by the Important Item Cultivation Foundation of Scientific Innovation Project of Colleges and Universities of China     

反应温度对微波法合成Fe2V4O13光催化粉体及其光催化性能的影响

以Fe（NO3）3·9H2O和NH4VO3为原料,采用微波水热-煅烧两步法合成了片层状结构单斜相Fe2V4O13光催化剂．以罗丹明B溶液为目标降解物,对不同煅烧温度下合成的Fe2V4O13粉体的光催化性能进行了研究．结果表明：随着煅烧温度的升高,片层状颗粒不断长大,Fe2V4O13光催化剂的结晶性能逐渐增强,粉体的比表面积逐渐减小．350℃和550℃下制备出的片层状粉体分别是由300nm大小及1Arm大小的小颗粒和块状颗粒聚集生长而成,二者都不利于光催化性能的提高;450℃煅烧合成的Fe2V4O13粉体晶化强度良好且粉体间团聚现象较小,具有较大的比表面积,光催化反应活性位点多,有利于光催化反应的进行．该温度下合成的Fe2V4O13粉体在紫外光照射240rain后对罗丹明B溶液的降解率可达到79．0％．