摘要
三草酸合铁(Ⅲ)酸钾具有工业生产价值,其合成作为化学专业本科生的经典实验项目,按教材实验的效果却不尽人意。本文在严谨的化学平衡理论分析基础上,首次提出提高合成产率的关键是严格控制草酸和草酸钾的用量,改进后的合成条件为:氧化步骤H_2O_2的浓度为6%,水浴温度为40°C;充分氧化后,微沸2分钟;酸溶步骤中草酸稍微过量,草酸钾过量10%;结晶时做到充分冷却。经此改进,可简化操作,节约原料,实验室平均产率达87%,教学中学生实验平均产率超过70%。
Potassium tris(oxalato) ferrate(III) trihydrate has the industrial production value, and its synthesis is a classic experiment in the laboratory course for chemistry majors. However, results from the experimental procedure in the textbook are unsatisfactory. Based on the rigorous analysis of chemical equilibrium theory, we first proposed that the key factor for improving the yield is to strictly control the amount of oxalic acid and potassium oxalate. The improved synthesis conditions are as follows: in the oxidation step, the reaction is carried out at 40 oC, and the concentration of H2O2 is 6%; after full oxidation,the solution is kept boiling for two minutes; a slight excess of oxalic acid and 10% excess of potassium oxalate are used in the acid dissolution step; sufficiently cooling is followed in crystallization. With the improved procedure, operations are simplified and raw materials are saved. The yield is 87% for laboratory average and greater than 70% for students in the laboratory class.
作者
肖圣雄
王晓伦
柏爱玲
杨斌姣
郭贤丽
张禹
蒋建宏
刘文奇
XIAO Sheng-Xiong;WANG Xiao-Lun;BAI Ai-Ling;GUO Xian-Li;ZHANG Yu;JIANG Jian-Hong;LIU Wen-Qi;YANG Bin-Jiao(College of Chemical Biological and Environmental Engineering, Xiangnan University, Chenzhou 423043, Hunan Province, P. R. China)
出处
《大学化学》
CAS
2016年第7期72-76,共5页
University Chemistry
基金
湖南省普通高校“十二五”专业综合改革试点项目(湘教通[2012]266号)
湖南省普通高校实践教学建设项目(湘教通[2013]295号)
湘南学院教学改革研究重点项目(湘南学院校发[2013]240号)
关键词
三草酸合铁(III)酸钾
配合物
合成
化学平衡
Potassium tris(oxalato) ferrate(III) trihydrate
Complex
Synthesis
Chemical equilibrium