交联剂用量对氨基功能化纳米Fe3O4磁性高分子材料吸附性能的影响

采用悬浮聚合法经共聚、开环反应, 得到了3种具有核-壳结构、以乙二胺为官能团的氨基功能化纳米Fe₃O₄磁性高分子材料(EDA-NMPs). 考察了其作为吸附剂对废水中Cr(Ⅵ)的吸附性能, 优化了最佳吸附实验条件, 并着重研究了高分子聚合过程中交联剂二乙烯基苯(DVB)的用量对所得EDA-NMPs材料吸附性能的影响. 结果表明, 材料合成过程中DVB的用量对EDA-NMPs的吸附性能有显著影响. 在最佳吸附条件(pH 2.5, T = 35℃)下, 共聚过程中不添加交联剂二乙烯基苯(DVB)时得到的材料对Cr(Ⅵ)的饱和吸附量(q_m)最大, 可达135.14 mg•g⁻¹, 初始吸附速率为1111.1 mg•g⁻¹•min⁻¹, 以3种吸附剂处理浓度为50 mg•L⁻¹的含Cr(Ⅵ)废水时, 去除率均超过99%, Cr(Ⅵ)的剩余浓度低于0.31 mg•L⁻¹, 达到国家排放标准(≤0.5 mg•L⁻¹).

The effect of the crosslink agent usage amount on the NH_2-functionalized nano-Fe_3O_4 magnetic composites

Three ethylenediamine (EDA) functionalized, core-shell structured, nano magnetic polymer adsorbents (EDA-NMPs) have been obtained via co-polymerization and ring-opening reactions. Their adsorption abilities on Cr(Ⅵ) in wastewater and the optimized adsorption condition have been investigated. The effect of the amount of the crosslink agent, i.e., divinylbenzen (DVB), used in the co-polymerization synthesis procedure, on the adsorption properties of the EDA-NMPs for the removal of Cr(Ⅵ) in wastewater was studied. The results showed the adsorption capacity was highly affected by the pH value, the initial concentration of Cr(Ⅵ), and the amount of DVB used for the prepreation of the adsorbents. The adsorption data taken at the optimized condition, i.e., at 35°C and pH 2.5, was well fitted with the Langmuir isotherm. The highest maximum adsorption capacity (qm) at 135.14 mg g⁻¹ and the initial adsorption rate (k²q²e.c) at 1111.1 mg g⁻¹ min⁻¹ were obtained for the EDA-NMPs without DVB used at co-polymerization procedure. By using the present NMPs to treat the Cr(Ⅵ) contained wastewater at concentration 50 mg L⁻¹, the adsorption efficiency for Cr(Ⅵ) reached to more than 99% with the concentration of Cr(Ⅵ) residue less than 0.31 mg L⁻¹, reaching the national standard for wastewater discharge(≤0.5 mg L⁻¹).