土壤中硫化物预处理方法的改进

Improvement in the pretreatment Method of Sulfides in soil

通过对土壤中硫化物测定预处理方法━━━━氮气吹气法的试验装置、预处理酸度、温度、吹气时间及载气速度等条件的研究和改进。以多孔吹球代替单孔吹管 ,在土壤的水溶液中加入NaOH、EDTA和Vc ,以NaOH -EDTA -TEA(三乙醇胺)代替Zn(Ac)2-NaAc为吸收液 ,并采取了逐步加压吹气方法 ,通过对回收率、精密度及底泥对比试验 ,效果提高显著 ,回收率由原方法的40%～60 %提高到90 %以上 ,吹气时间缩短了20 % ,装置简单 ,便于推广应用。

The pretreatment method of sulfides in soil, known as N2-blowing method, has been further studied and improved. The improvement includes the test apparatus, acidity, temperature and timing of blowing, and blowing rate during the pretreatment .Particularly, a multi-hole blowing ball was used to replace the singe hole blowing pipe, and NaOH、EDTA and Vc was added to soil solution, and a mixture of NaOH ,EDTA and TEA was used as absorbing solution instead of Zn(Ac)2-NaAc. Then a stepwise pressure-increasing procedure has been suggested. After implementation of new method through comparison test for the recovery, precision and base mud, the results show that recovery rate has been increased from 40%～60% to 90%, and blowing period is shortened by 20%.The apparatus is simple to operate.