贵州黄壤、石灰土的重金属吸附解吸特性

发布时间：2018-06-25 23:34

本文选题：贵州 + 重金属　；参考：《科学技术与工程》2017年29期

【摘要】：以贵州省典型土壤黄壤和石灰土为研究对象,采用野外调查和室内分析相结合的方法,对贵州土壤重金属吸附解吸特性进行研究。结果表明:贵州地区重金属超标率石灰土黄壤;石灰土的p H缓冲性能大于黄壤;且碳酸钙含量增加到90 g/kg时,黄壤的p H将不在增加,p H稳定在7.08;碳酸钙含量增加到120 g/kg时,石灰土p H将不再增加,稳定在8.26;而增加黏粒含量对土壤p H无明显作用;除了石灰土中的Cr和As,无论黄壤还是石灰土,复合污染土壤重金属的吸附固持的作用随碳酸钙含量的增加而增强;而随着黏粒含量的增加,黄壤和石灰土的吸附量都有所增加;但解吸量无明显促进或降低,即碳酸钙影响该地区土壤重金属蓄积的作用大于黏粒。黄壤和石灰土对重金属的吸附过程主要集中在前90 min内,其后的吸附则进行得十分缓慢;且对重金属的最大吸附量石灰土黄壤;三种动力学模型拟合中,伪二级动力学方程的拟合度最好。从动力学参数中可知,石灰土重金属平均吸附量大于黄壤重金属平均吸附量,黄壤重金属平均吸附速率大于石灰土重金属平均吸附速率。
[Abstract]:The adsorption and desorption characteristics of heavy metals in typical soils of Guizhou Province were studied by means of field investigation and laboratory analysis. The results showed that heavy metal content exceeded the standard of lime soil in Guizhou, pH buffer capacity of lime soil was higher than that of yellow soil, and pH of yellow soil was stable at 7.08 when calcium carbonate content increased to 90 g/kg, and calcium carbonate content increased to 120 g/kg. The pH of lime soil will no longer increase, stable at 8.26, and the increase of clay content has no obvious effect on soil pH. Except for Cr and Asin in lime soil, whether yellow soil or lime soil, The adsorption and retention of heavy metals increased with the increase of calcium carbonate content, while the adsorption capacity of yellow soil and lime soil increased with the increase of clay content, but the desorption amount was not significantly promoted or decreased. The effect of calcium carbonate on the accumulation of heavy metals was greater than that of clay. The adsorption process of heavy metals on yellow soil and lime soil was mainly concentrated in the first 90 min, and the adsorption of heavy metals later was very slow, and the maximum adsorption amount of heavy metals was lime soil yellow soil. The pseudo-second order kinetic equation has the best fitting degree. From the kinetic parameters, it can be seen that the average adsorption capacity of heavy metals in lime soil is larger than that in yellow soil, and the average adsorption rate of heavy metals in yellow soil is higher than that in lime soil.
【作者单位】：贵州大学生命科学学院;贵州省中国科学院天然产物化学重点实验室;贵州医科大学生命科学学院;
【基金】：国家自然科学地区基金(41561075) 贵州省科技厅2015年度科研机构服务企业行动计划(黔科合服企[2015]4008号) 贵州特色药用资源的创新药物研发团队及平台建设项目(黔科合体Z字[2014]4007号)资助
【分类号】：X53

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