Abstract:

Coal to calcium carbide (CaC₂) acetylene process occupies an important position in the coal chemical industry in China. However, it has been restricted by high power consumption and heavy carbon dioxide emission in the industrial production of its key intermediate calcium carbide. Therefore, it is of great significance to develop a green and environment-friendly alternative process to replace calcium carbide production in coal to acetylene. In this paper, barium carbide was utilized to produce acetylene synthesized from the mixture of barium carbonate with carbon. The characteristics of the BaC₂ synthesis reaction system were analyzed from the perspective of thermodynamics, and the experimental verification of the synthesis of BaC₂ was carried out at 1550℃. The results showed that a new route for converting carbon and carbon dioxide into acetylene and carbon monoxide via BaCO₃-BaC₂-Ba(OH)₂-BaCO₃ barium cycle by replacing CaC₂ with BaC₂ as the key intermediate of coal-to-acetylene has the advantages of low reaction temperature and zero reaction temperature. The easy regeneration and reuse of barium carbide would highlight barium-based sustainable chemical technologies as promising instruments for total carbon recycling, which provide new methods for the development of the modern coal chemical industry.

Key words: acetylene, barium carbide, barium circulation, thermodynamics, CO₂ capture, chemical processes

摘要：

煤制电石(CaC₂)乙炔工艺在我国煤化工行业中占有重要地位。但其关键中间体CaC₂的工业生产过程具有反应温度高、能耗大、CO₂排放严重等问题，严重制约了电石及下游相关产业的发展。开发绿色环保的煤制电石替代工艺具有重要意义。本研究提出采用BaC₂替代CaC₂作为煤制乙炔工艺的关键中间体，从热力学角度分析了BaC₂合成反应体系的特点，并在1550℃进行了合成BaC₂的实验验证。结果表明，以BaC₂替代CaC₂为煤制乙炔的关键中间体、通过BaCO₃-BaC₂-Ba(OH)₂-BaCO₃的钡循环将碳和二氧化碳转化为乙炔和一氧化碳的新路线，具有反应温度低、零CO₂排放、联产CO、固废排放少等优点，可以为现代煤化工的绿色发展提供新的思路。

关键词: 乙炔, 碳化钡, 钡循环, 热力学, 二氧化碳捕集, 化学过程