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香蕉假茎粉末等天然吸附剂对于去除废水中的重金属元素具有非常重要的作用。现有的去除重金属元素的常规方法难以满足水资源循环和化学工业的需求。本文论证了利用天然物质处理废水的可能性。利用环境扫描电子显微镜(ESEM)和傅里叶变换红外(FTIR)光谱学分析方法,研究了香蕉假茎粉末吸附铅离子前后的变化。实验采用批处理方法研究了水溶液中铅离子去除的效果。通过改变初始p H值、吸附剂用量、初始铅离子浓度、吸附时间等参数,研究了吸附动力学的影响。结果表明,在水溶液p H值为5.5时,香蕉假茎粉末达到零电荷点。采用吸附等温线和动力学模型分析实验数据,采用朗缪尔吸附等温式拟合铅离子在香蕉假茎粉末表面的吸附作用。实验表明,香蕉假茎粉末对铅离子的吸附量为34.21 mg·g~(–1),与拟二级动力学模型相匹配。此外,采用响应面分析法确定了铅离子吸附的最佳条件,铅离子的去除率高达89%。
Natural adsorbents such as banana pseudostem powder play a very important role in removing heavy metal elements in wastewater. Existing conventional methods of removing heavy metal elements can not meet the needs of the water cycle and chemical industry. This article demonstrates the possibility of using natural materials for wastewater treatment. The change of Pb ion adsorption on banana pseudostem powder was studied by using environmental scanning electron microscopy (ESEM) and Fourier transform infrared spectroscopy (FTIR) spectroscopy. The experiment uses the batch method to study the effect of lead ion removal in aqueous solution. By changing the initial p H value, the amount of adsorbent, initial lead ion concentration, adsorption time and other parameters, the adsorption kinetics was studied. The results showed that the banana pseudostem powder reached a zero charge point when pH of aqueous solution was 5.5. Adsorption isotherms and kinetic models were used to analyze the experimental data. Langmuir adsorption isotherm was used to fit the adsorption of Pb ions on the surface of banana pseudostem powder. Experiments show that the adsorption capacity of banana pseudostem powder to lead ions is 34.21 mg · g ~ (-1), which matches the pseudo-second-order kinetic model. In addition, response surface methodology was used to determine the optimum conditions for lead ion adsorption, with lead ion removal as high as 89%.