钼酸铅重量法测定铁钼催化剂中钼含量
Determination of molybdenum in iron-molybdenum catalyst by lead molybdate gravimetric method
李方杰 1佡云 1马晓卉1
作者信息
- 1. 沈阳有色金属研究院有限公司,辽宁沈阳 110141
- 折叠
摘要
铁钼催化剂材料在化工领域应用十分广泛,不同钼含量的铁钼催化剂在不同的催化反应中具有不同的催化性质和催化效果,钼含量的准确分析对铁钼催化剂的生产具有指导作用.目前国家标准和行业标准中针对钼含量的测定分析主要是钼铁(钼含量50％～75％)和钼精矿(钼≥40％),而铁钼催化剂中钼含量通常在20％～50％之间,且含有其他元素,样品前处理方法与国家标准和行业标准存在差别,需要建立新的分析条件参数满足生产需求.本研究考察了溶样条件、沉淀生成参数、灼烧温度等对测定结果的影响,对条件参数进行了优化,确定最佳条件为四酸(HCl+HNO3+HF+HClO4)溶样法溶解样品、乙酸铅沉淀剂滴加速度3～5滴/s、沉淀陈化时间45 min、陈化温度70 ℃、沉淀洗涤次数15次、沉淀灼烧温度550 ℃,在此条件参数下,钼酸铅重量法可有效分析铁钼催化剂中钼的含量,相对标准偏差在0.20％以下,样品的加标回收率在98.0％～101.4％之间,能够满足铁钼催化剂中钼含量测定的准确分析要求.但由于钨对钼含量测量产生干扰,因此本试验方法不适用于含钨的铁钼催化剂试样.
Abstract
Iron-molybdenum catalyst materials are widely used in the chemical industry field,and have different catalytic properties and catalytic effects in different catalytic reactions because of different molybdenum contents.So the accurate analysis of molybdenum content has a guiding role in the production of iron molybdenum catalyst.At present,the determination and analysis of molybdenum content in national standards and industry standards are mainly molybdenum iron(molybdenum content 50％-75％)and molybdenum concentrate(molybdenum ≥40％),while the molybdenum content in iron molybdenum catalyst is usually between 20％-50％,and contains other elements.The sample pretreatment method is different from the national standards and industry standards,and it is necessary to establish new analysis parameters to meet the production needs.In this study,the effects of sample dissolution conditions,precipitation formation parameters and calcination temperature on the determination results were investigated,and the condition parameters were optimized.The optimum conditions were determined as follows:the sample was dissolved by four acid(HCl+HNO3+HF+HClO4),the dropping speed of lead acetate precipitant was 3～5 drops/s,the precipitation aging time was 45 min,the aging temperature was 70 ℃,the precipitation washing times was 15 times,and the precipitation burning temperature was 550 ℃.Under these conditions,the content of molybdenum in iron-molybdenum catalyst can be effectively analyzed.The relative standard deviation is below 0.20％,and the recovery rate of the sample is 98.0％-101.4％,which can meet the requirements of molybdenum content determination in iron-molybdenum catalyst.However,due to the interference of tungsten on the measurement of molybdenum content,this test method is not suitable for iron-molybdenum catalyst samples containing tungsten.
关键词
钼酸铅重量法/铁钼催化剂/钼测定/溶样条件/沉淀生成参数/灼烧温度/钨Key words
lead molybdate gravimetric method/iron-molybdenum catalyst/molybdenum determination/sample dissolution conditions/precipitation formation parameters/ignition temperature/tungsten引用本文复制引用
出版年
2024
NETL
NSTL
万方数据