通过采用2,2,6,6-四甲基哌啶氮氧自由基(TEMPO)/NaBr/NaClO体系来选择性催化氧化纤维素,并将制得的氧化纤维素(TOC)用于Pb2+的吸附。结果表明:TOC对Pb2+溶液吸附的最佳pH为5。不同羧基含量的TOC对于Pb2+溶液的吸附,随着羧基含量的增大,其吸附量也在增大且在一定范围内符合线性关系。对于Pb2+的吸附行为更符合Freundlich吸附等温线方程,最大饱和吸附量为138.82mg/g,循环使用性能良好;将TOC通过超声波细胞粉碎机处理纳米化,处理时间为20min时,粒度最小,纤维素吸附量/吸附率最高。
The TEMPO/NaBr/NaClO system was used to selectively catalyze the oxidation of cellulose,and the obtained oxidized cellulose (TOC) was used for the adsorption of Pb2+.The results showed that the optimum pH of TOC adsorption on Pb2+ was 5.The adsorption capacity of TOC on Pb2+ solution increased with the increase of carboxyl content,showing a linear relationship to a certain extent.The adsorption behavior of Pb2+ was more in line with the Freundlich adsorption isotherm equation.The maximum saturated adsorption capacity was 138.82mg/g,and the cycle performance was good.The oxidized cellulose was treated by ultrasonic cell pulverizer for nanomerization.When the treatment time was 20min,the smallest particle size was obtained and the adsorption/adsorption rate of cellulose was the highest.
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