试剂硫酸产品脱除硝酸盐的实验研究(一)

Experimental Study on Nitrate Removal from Sulphuric Acid Products with Reagent(Ⅰ)

硝酸盐是试剂硫酸产品的关键技术指标之一,国家标准《化学试剂硫酸》(GB/T 625-2007)中规定了分析纯硫酸中硝酸盐含量须≤0.00005%。尿素脱硝是比较通行的脱硝方法,但脱硝效果受多重因素影响。本文经研究发现,以0.25 mL浓度在40%~50%的尿素试剂溶液与10 mL含硝酸盐浓度为3 mg/L的质量分数为98.3%硫酸试样,在适当的温度和反应时间下,转换效率高、副反应低,具有良好的脱硝效果,可以使硫酸试样中硝酸盐浓度稳定达到GB/T 625-2007分析纯硫酸标准的要求。该研究可为生产工艺改善提供参考依据。

Nitrate is one of the key technical indicators of reagent sulfuric acid products.Our national standard“Chemical Reagents Sulfuric Acid”(GB/T 625-2007)stipulates that the nitrate content in analytical pure sulfuric acid must be≤0.00005%.Urea denitrification is a commonly used denitrification method,but the denitrification effect is influenced by multiple factors.Through research,it was found that using 0.25 mL of urea reagent solution with a concentration of 40%to 50%and 10 mL of sulfuric acid sample with a mass fraction of 3 mg/L of nitrate as 98.3%,under appropriate temperature and reaction time,the conversion efficiency was high,the side reactions were low,and the denitrification effect was good.The nitrate concentration in the sulfuric acid sample could be stabilized to meet the requirements of the GB/T 625-2007 analysis standard for pure sulfuric acid.This study could provide a reference basis for improving production processes.