羧酸型接枝淀粉吸附树脂的制备和对染料的去除性能

以天然淀粉(RS)为基体、以丙烯酸(AA)和乙酸乙烯酯(VAc)为原料在过硫酸铵(APS)和亚硫酸氢钠(SHS)的引发下用水相合成法制备羧酸型接枝淀粉吸附树脂(CSR),使用SEM、IR、XRD、13C-NMR和GPC等手段表征树脂的结构,研究其对染料的去除性能.结果表明:当引发剂的浓度为0.03mol/L、单体物质量...

Preparation of Carboxylic Acid Grafted Starch Adsorption Resin and Its Dye Removal Performance

Carboxylic acid grafted starch adsorption resin (CSR) was synthesized by using natural starch (RS) as matrix, acrylic acid (AA) and vinyl acetate (VAc) as raw materials in the presence of ammonium persulfate (APS) and sodium bisulfite (SHS). The resulted CSR product was characterized by SEM, IR, XRD, ¹³C-NMR and GPC. The results show that when the initiator concentration was 0.03 mol/L, the monomer mass ratio n (AA): n (VAc) was 3:1 and the monomer concentration was 0.8 mol/l, the prepared CSR product presents the carboxyl group content of 19.26% with adsorption capacity of 17.35mg/g for malachite green, in other words, the water resistance and chemical stability and the tolerance to acid, alkali and enzyme of CSR resin were enhanced in comparison to those of the natural starch. After alkali treatment the adsorption capacity of the resin can be further improved. Linear molecules in CSR resin gradually transformed into branched type, resulting in complex network structure of macromolecules. The molecular mass of the main chain of CSR decreased with the increase of monomer dosage and AA / VAc ratio. The adsorption capacity of CSR for basic fuchsin (BF), methylene blue (MB) and malachite green (MG) is better than that of 001×7 strong acid ion exchange resin, D151 weak acid ion exchange resin, carboxymethyl cellulose CMC and carboxymethyl starch CMS and other synthetic and natural polymer adsorbents. The CSR has broad-spectrum of adsorption closed to that of active carbon. The zerocharge point pH_pzc of CSR was 3.83, which was much lower than that of natural starch resin (pH_pzc=7.38), that may be an important reason for the increase of adsorption capacity of cationic dyes. The CSR has good dye adsorption performance in a wide range of pH values, and the adsorption capacity reaches the maximum value when pH=8.5. The decolorization rate of CSR for mixed dye waste water was 87.42%. Finally the CSR had strong regeneration ability. Even after eight regeneration cycles, its decolorization rate was not lower than 88.6% of the initial adsorption ability.