水稻秸秆阴离子吸附剂的制备及其性能的研究

Preparation and characterization of anion adsorbent derived from rice straw

为了合理利用我国过剩的水稻秸秆,同时解决水体富营养化问题,将水稻秸秆通过化学修饰合成得到阴离子吸附剂,探究其对磷的去除效果.通过测定带电情况、比表面积、扫描电镜、红外光谱,分析该阴离子吸附剂的性能;同时考察了吸附剂投加量、磷酸根溶液初始pH值、温度等因素对吸附效果的影响,并分析了修饰后的水稻秸秆对磷酸根的吸附机理.结果表明：吸附剂投加量为5g/L,pH值为4~10时,对磷酸根的吸附效果最好,去除率达90%以上,而温度对吸附效果影响不大;Langmuir模型适用于修饰后的水稻秸秆对磷酸根的吸附,最大的吸附量达1.96mmol/g.

The rice straw was chemically modified to prepare anion adsorbent in order to utilize the excess rice straw in China reasonably and reduce eutrophication at the same time.Characteristics of the anion adsorbent derived from rice straw were analyzed using BET,SEM and FTIR analyzer.Meanwhile,the influence of the adsorbent dosage,initial pH of phosphoric acid solution and temperature to the adsorption capacity were also considered.The results indicated that the modified rice straw was able to absorb phosphate effectively within the pH range of phosphoric acid solution from 4.0 to 10.0 and the optimum adsorbent dosage was 5g/L.The adsorption data fitted the Langmuir adsorption isotherm very much and the maximum adsorption capacity was 1.96 mmol/g.