非水光电滴定法测定地质样品中二氧化碳  

Determination of carbon dioxide in geological samples by non-aqueous photoelectric titration method

作　　者：刘春霞[1] 钟盼[1] 李艳华[1] 杜文娟 冯兰慧 LIU Chun-xia;ZHONG Pan;LI Yan-hua;DU Wen-juan;FENG Lan-hui(Key Laboratory of Ministry of Land and Resources Analysis of Precious Metals,Henan Province Rock and Mineral Testing Center,Zhengzhou 450012,China;The Second Geological Exploration Institute of Henan Bureau of Geology and Mineral Resources Exploration and Development,Zhengzhou 450000,China)

机构地区：[1]国土资源部贵金属测定与勘查技术重点实验室,河南省岩石矿物测试中心,河南郑州450012 [2]河南省地质矿产勘查开发局第二地质勘查院,河南郑州450000

出　　处：《化学工程师》2023年第10期37-41,共5页Chemical Engineer

基　　金：河南省自然科学基金资助项目(豫自然资函[2021]157号-4)。

摘　　要：建立了非水光电滴定法测定地质样品中CO_(2)含量的方法。实验在微沸状态下,以10mL(1+1)磷酸消解样品,将碳酸盐消解为CO_(2),生成的气体经过除干扰装置后进入光电吸收池进行吸收和滴定。并对称样量、溶矿温度、气流量、酸的选择和用量、正负压供气及滴定方式等条件进行探讨。方法检出限(3S)为0.039%,定量限(10S)为0.13%。分别选择基准物质CaCO_(3)及国家一级标准物质GBW07108、GBW07104、GBW07110为测定对象,测定结果与认定值相符。方法的测定范围为0.13%~45%,相对标准偏差(RSD)为1.32%~3.38%,准确度(RE)为-2.21%~1.94%,回收率为94%~106%。采用该方法对地质样品进行测定,结果与重量法基本一致。本方法测定范围广,测定效率高,适合大批量样品的测定。A method for the determination of carbon dioxide in geological samples by non-aqueous photoelectric titrator was established.In the experiment,the sample was digested with 10mL(1+1)phosphoric acid in a slightly boiling state,and the carbonate was digested into carbon dioxide.The generated gas passed through the interference removal device and entered the photoelectric absorption cell for absorption and titration.The conditions of assampling amount,dissolution temperature,gas flow rate,selection and dosage of acid,positive and negative pressure gas supply,and titration method were also explored.The detection limit(3S)of the method was 0.039%,and the quantitative limit(10S)was 0.13%.The primary standard calcium carbonate and the national first-class reference materials GBW07108,GBW07104 and GBW07110 were selected as the test objects,and the test results were consistent with the certified values.The determination range of the method was 0.13%~45%,the relative standard deviation(RSD)was 1.32%~3.38%,the accuracy(RE)was-2.21%~1.94%,and the recovery rate was 94%~106%.The method was used to determine geological samples,and the results were basically consistent with the gravimetric method.This method has a wide measurement range and high efficiency,making it suitable for the determination and testing of large batches of samples.

关 键 词：非水滴定法 二氧化碳 光电滴定仪 供气方式 地质样品 

分 类 号：O65.22[理学—分析化学]