微波法合成硫脲树脂及其吸附性能研究

Synthesis of Thiourea-resin by Microwave Irradiation and its Adsorption Properties

研究了硫脲、甲醛、对苯二酚的聚合,比较了微波辐射和常规加热对树脂产率的影响,考察了不同条件下树脂对金属离子的吸附情况。用核磁共振和红外光谱对树脂可能含有的官能团进行表征。结果表明:微波辐射与常规加热相比具有反应时间短、产率高的优点。酸性条件下树脂对Ag+的最高吸附量可达2.2mmolg-1,而相同条件下对Ni2+、Cd2+、Co2+等过渡金属离子基本不吸附,体现了该树脂在对金属离子的选择分离方面有较高的应用价值。利用含8%硫脲的1molL-1HNO3溶液洗脱经吸附过的树脂,洗脱率可达95%以上,再生的树脂吸附量仍可达到前一次的98%。

Thiourea, formaldehyde and hydroquinone were copolymerized to produce the thiourea-resins using microwave irradiation and conventional method respectively. The resin's yield, the H-NMR and IR of the resin and the adsorption of metal ions on the resin under different conditions were investigated. The results show that microwave irradiation has higher yield and less polymerization time than the conventional method, but the resins produced by two methods have the similar structures. The maximum adsorption capacity of Ag+ is 2.2 mmol&middotg-1 with neglectable adsorption capacities of Ni2+, Co2+ and Cd2+. Therefore, resin produced has high application value in recovering noble metal ions. 1 mol&middotL-1 HNO3 solution with 8% thiourea was used to desorb resins. The desorption ratio reaches 95% and the desorbed resin can be reused. The adsorption ratio of the reused resin is 98% of the original.