快速加热容量法测定土壤中有机质含量  

Determination of organic matter in soil by rapid heating volumetry method

作　　者：马熠罡 任收讲 高翔宇 李皓 李湘 高航 MA Yigang;REN Shoujiang;GAO Xiangyu;LI Hao;LI Xiang;GAO Hang(Xi’an Northwest Nonferrous Geological Research Institute Co.,Ltd.,Xi’an 710054,China)

机构地区：[1]西安西北有色地质研究院有限公司,西安710054

出　　处：《化学分析计量》2018年第6期110-112,共3页Chemical Analysis And Meterage

摘　　要：建立快速容量法测定土壤中有机质的分析方法。采用恒温电热板控温加热替代油浴加热溶解样品,使用硫酸银作为催化剂,重铬酸钾–硫酸标准溶液作为氧化剂,使用硫酸亚铁铵溶液为滴定剂,测定土壤中有机质含量。优化后的分析条件:溶样温度为220℃,溶样时间为(5.5±0.5) min,催化剂用量为0.08 g。对3个国家一级标准物质进行分析,测定结果与推荐值相符,相对误差为–4.0%～0.0%,相对标准偏差为1.17%～3.66%(n=6)。该法可用于大批量土壤样品中有机碳含量的快速测定。A rapid heating volumetry method was established for determining organic matter in soil.By this method temperature control heating was used instead of oil bath heating to dissolve sample,and silver sulfate was used as a catalyst,potassium dichromate–sulfuric acid standard solution was as oxidant,and ferrous ammonium sulfate solution was used as titrant to determine the organic matter content in soil.The method conditions optimized were as the following:the dissolution temperature of 220℃,the dissolution time of(5.5±0.5)min,and the dosage of catalyst of 0.08 g.The detection results of three CRM were consistent with the standard values with the relative error of–4.0%–0.0%,and the relative standard deviations were 1.17%–3.66%(n=6).This method is suit for rapid determination of organic matter in soil with mass samples.

关 键 词：土壤 有机质 控温加热 氧化条件 

分 类 号：O656.3[理学—分析化学]