废弃印刷线路板熔融盐气化特性研究

Study on gasification characteristics of waste printed circuit boards (PCB) in molten salts

在熔融盐气化炉中进行废弃印刷线路板气化实验,考察了空气当量比对气体产率、气体热值、碳转化率以及气化效率的影响,并对N2气氛下线路板在熔融盐反应器中裂解液体产物通过气质联用仪进行了分析.结果表明,气体产率和碳转化率随着空气当量比增加而增加,空气当量比增加到40%时,气体产率和碳转化率分别达到840mL·g-1和96%;气体产物热值随着空气当量比增加而减少,气化效率随着空气当量比的增加先增加然后减少,在20%空气当量比气化效率达到最大值94%.液体产物的主要成分为苯酚、2-甲基苯酚、萘等,表明线路板在熔融盐气化炉内的反应过程中,苯环结构上的长链烷烃脂肪烃支链得到脱除,苯基C6H5-O的断裂得到加强,同时发生芳构化反应.

Gasification of waste printed circuit boards （PCB） was carried out in a molten salt reactor to investigate the effect of equivalence ratio （ER） on the gasification reaction. The gas yield and carbon conversion rate increased with the equivalence ratio. When ER increased to 40%, the gas yield reached 840 mL-g^-1 and the carbon conversion was 96%. The gas heating value decreases with ER, and the gasification efficiency first increased, then decreased with ER, reaching a maximum of 94% when ER was 20%. The liquid PCB pyrolysis products in the molten salt were analyzed by gas chromatography- mass spectrometry （GC-MS）. The main liquid products were identified as phenol, 2-methylphenol, 4-methylphenol, and naphthalene indicating a total splitting of phenyl and long-chain alkyl or aliphatie branches, and an enforced splitting of C （phenyl）-O, and aromatization reaction happening during the pyrolysis of PCB in molten salt.