土壤消解前处理过程赶酸时间对土壤中总铬测定结果的影响探究

Study on the Influence of Acid Removal Time in Soil Digestion Pretreatment Process on the Determination Results of Total Chromium in Soil

土壤中重金属元素总铬的测定结果经常受土壤前处理消解过程的影响,造成测定结果偏低,消解前处理的具体步骤决定了分析测定结果的准确性。在进行大规模土壤样品前处理时,需要兼顾准确性和前处理效率。在全消解法和微波消解法的选择中,因为微波消解法有速度快、成本低及污染小的优点,更适用于大批量土壤样品的前处理。本文以此为背景,首先介绍了微波消解、土壤消解前处理赶酸时间的定义,随后,在探讨和实验土壤前处理微波消解法消解的过程中,通过减少赶酸时间和赶酸过程是否加盖来进行比对。本研究采用《土壤质量总铬的测定火焰原子吸收分光光度法》(GB/T 17137-1997)[1],并使用原子吸收分光光度仪进行验证,发现适当缩短赶酸时间可以减少前处理过程中总铬的损失,从而提高了测定值的准确性。希望这些研究能够给人以启发,为日后进行类似大批量土壤样品的前处理提供有价值的参考。

The determination results of total chromium,a heavy metal element in soil,are often influenced by the digestion process of soil pretreatment,which leads to the low determination results.The specific steps of digestion pretreatment determine the accuracy of the analysis and determination results.In the pretreatment of large-scale soil samples,both accuracy and pretreatment efficiency need to be considered.In the selection of total digestion method and microwave digestion method,microwave digestion method is more suitable for the pretreatment of large-scale soil samples because of its advantages of high speed,low cost and little pollution.Based on this background,this paper first introduces the definition of acid rush time in microwave digestion and soil digestion pretreatment,and then compares the reduction of acid rush time and whether the acid rush process is covered in microwave digestion of soil pretreatment.It is verified by flame atomic absorption spectrophotometry for determination of total chromium in soil quality(GB/T 17137—1997)[1],and it is found that shortening the acid rush time properly can reduce the acid rush time in the pretreatment process.I hope it can inspire people and provide valuable reference for the pretreatment of similar large quantities of soil samples in the future.