废弃印刷电路板材料裂解产物的高分辨裂解气相色谱-质谱分析

Characterization of pyrolysis of waste printed circuit boards by high-resolution pyrolysis gas chromatography-mass spectrometry

采用高分辨裂解气相色谱-质谱法(PyGC-MS)分析了FR-4型印刷电路板粉末样品的裂解产物。在氦气氛围中,分别在350,450,550,650和750℃下对印刷电路板粉末样品进行热裂解,并通过毛细管气相色谱-质谱对裂解产物进行分析,研究了不同裂解温度下裂解产物分布以及主要裂解产物的产率与裂解温度的关系,根据热分解产物的组成,探讨了热分解反应机理。

Thermal degradation of pyrolysis of waste circuit boards was investigated by high-resolution pyrolysis gas chromatography-mass spectrometry （PyGC-MS） and thermogravimetry （TG）. In helium atmosphere, the products of FR-4 waste printed circuit board were pyrolyzed at 350, 450, 550, 650, and 750 ℃, separately, and the pyrolysis products were identified by online MS. The results indicated that the pyrolysis products of the FR-4 waste circuit board were three kinds of substances, such as the low boiling point products, phenol, bisphenol and their related products. Moreover, under 300 ℃, only observed less pyrolysis products. As the increase of pyrolysis temperature, the relative content of the low boiling point products increased. In the range of 450 - 650 ℃, the qualitative analysis and character were similar, and the relative contents of phenol and bisphenol were higher. The influence of pyrolysis temperature on pyrolyzate yields was studied. On the basis of the pyrolyzate profile and the dependence of pyrolyzate yields on pyrolysis temperature, the thermal degradation mechanism of brominated epoxy resin was proposed.