利用热重(TG)法进行了聚四氟乙烯(PTFE)型印刷线路板不同升温速率的热解特性实验研究,建立了表观热解反应动力学模型.利用固定床热解试验装置进行了PTFE线路板热解实验,利用气-质联用(GC—MS)和扫描电镜(SEM)分别检测了热解气体和固体产物.结果表明:a.所建热解模型与实验数据符合较好,求得动力学三参数分别为活化能223.606kJ/mol,反应级数0,指前因子1.529×10^13min^-1;b.热解气体产物主要为八氟环丁烷.手动剥离即可实现金属和玻璃纤维等组分的分离富集.富集的金属片主要为铜片及其镀层上含有少量的金、镍等贵重金属;富集的玻璃纤维中含有大量的碳,还有一定量的O,F,Al,Si,Ca,Ti等元素.
Pyrolysis characteristics of waste polytetrafluoroethylene(PTFE)-printed circuit boards were investigated under different heating rates with thermogravimetry (TG). A kinetic model for expressing the pyrolysis reaction was established. A fixed-bed experimental apparatus was used to pyro lyze the printed circuit boards and the products were analysised by using gas chromatograph and mass spectrometer (GC-MS) and scanning electronic microscopy (SEM). The results show: a. the kinetics model was in good agreement with the experimental ones at four heating rates, the kinetics parameters of polytetrafluoroethylene-type printed circuit boards was zero-order for reaction order, 223. 606 kJ/mol for the activation energy, 1. 529× 1013 min ^-1 for pre-exponential factor; b. octafluorocyclobutane was the main content of the pyrolysis gas. Glass fiber and metallic fractions were easily seperated and accumulated. The accumulated metals were mainly copper strip and a bit golden and nickel were plated on the strips. The enriched glassfibre consists of amount of carbon and significant concentra- tions of O,F,AI,Si,Ca,Ti.