Department of Polymer Materials, Kun Shan University, No. 949 Da-Wan Rd., Yung-Kang City, Tainan Hsien, Taiwan, ROC.
J Hazard Mater. 2009 Nov 15;171(1-3):465-70. doi: 10.1016/j.jhazmat.2009.06.144. Epub 2009 Jul 3.
Methacrylic acid (MAA) grafted rice husk was synthesized using graft copolymerization with Fenton's reagent as the redox initiator and applied to the adsorption of paraquat. The highest grafting percentage of 44.3% was obtained using the traditional kinetic method. However, a maximum grafting percentage of 65.3% was calculated using the central composite design. Experimental results based on the recipes predicted from the statistical analysis are consistent with theoretical calculations. A representative polymethacrylic acid-g-rice husk (PMAA-g-rice husk) copolymer was hydrolyzed to a salt type and applied to the adsorption of paraquat. The adsorption equilibrium data correlate more closely with the Langmuir isotherm than with the Freundlich equation. The maximum adsorption capacity of modified rice husk is 292.5mg/g-adsorbent. This value exceeds those for Fuller's earth and activated carbon, which are the most common binding agents used for paraquat. The samples at various stages were characterized by solid-state (13)C NMR spectroscopy.
采用 Fenton 试剂作为氧化还原引发剂的接枝共聚反应，合成了接枝到稻壳上的甲基丙烯酸（MAA），并将其应用于百草枯的吸附。使用传统动力学方法，接枝率最高可达 44.3%。但是，使用中心复合设计计算出的最大接枝率为 65.3%。基于统计分析预测的实验结果与理论计算相符。从代表性的聚甲基丙烯酸接枝到稻壳（PMAA-g-rice husk）共聚物中水解得到盐型，并将其应用于百草枯的吸附。吸附平衡数据与 Langmuir 等温线的相关性优于 Freundlich 方程。改性稻壳的最大吸附容量为 292.5mg/g-吸附剂。这个值超过了最常用的百草枯结合剂——凹凸棒土和活性炭。采用固态（13）C NMR 光谱对各阶段的样品进行了表征。
