TG-FTIR-MS联用分析一水硫酸四氨合铜(Ⅱ)水和氨分子热失重脱除历程

Removal Process of Water and Ammonia Molecules of Thermal Weight Loss Process of Tetraamminecopper(Ⅱ)Sulfate Monohydrate Based on TG-FTIR-MS Hyphenated Analysis

一水硫酸四氨合铜(Ⅱ)(Cu(NH_(3))_(4)SO_(4)·H_(2)O)的制备及组成测定是一个重要的综合化学实验,但是对其水和氨分子热失重脱除历程的研究鲜见文献报道。由于NH3和H2O的摩尔质量接近,很难只凭借热重和差热曲线判断每个失重平台对应的反应,因此将热重-差热(TG-DTA)和热重-傅立叶红外光谱-质谱(TG-FTIR-MS)联用技术用于Cu(NH_(3))_(4)SO_(4)·H_(2)O的热分析研究。明确了Cu(NH_(3))_(4)SO_(4)·H_(2)O在升温过程中发生的化学变化,有助于提升学生对热分析曲线的分析能力,丰富了该实验项目的内容。同时通过对热分析曲线的解读,提出了一种可能存在但未见报道的新物质,为后续的进一步研究提供方向。

The preparation and composition determination of tetraamminecopper(Ⅱ)sulfate monohydrate(Cu(NH_(3))_(4)SO_(4)·H_(2)O)is an important comprehensive chemical experiment.However,there were insufficient references and reports on its thermal weight loss in removing water and ammonia.It is difficult to judge the corresponding reaction of each weight-loss platform only by thermogravimetric and differential thermal curves due to the molar mass of NH_(3) and H_(2)O were very close.Therefore,hyphenated technology of thermogravimetric-differential thermal analysis(TG-DTA)and thermogravimetric-Fourier transform infrared radiation-mass spectrometry(TG-FTIR-MS)were applied to analyze Cu(NH_(3))_(4)SO_(4)·H_(2)O,which clarified the chemical changes of Cu(NH_(3))_(4)SO_(4)·H_(2)O during the process of temperature rise,promoted the students'analysis capability on thermal analysis curve and enriched the content of Cu(NH_(3))_(4)SO_(4)·H_(2)O experiment project.Meanwhile,a new substance that might exist but without available realistic report was proposed through interpreting the thermal analysis curve,which worth to study more.