Research On The Pyrolysis Characteristics Of Waste Printed Circuit Board Substrate

The topic selects the most typical FR4type waste printed circuit boardsubstrate as a research object. First, analyzes the type FR4waste printed circuitboard substrate basic properties of the samples, the data show that waste printedcircuit board substrate elements of the most content for C, content is37.54%; Thesamples for the calorific value of the average12229.46J/g, for the follow-up ofpyrolysis reaction provides basic data. Based the results of the analysis, theexperiment began to use hot heavy analyzer and hot heavy-near infraredspectrometry technique to study the heating rate, samples and catalyst particlesize experimental conditions to heat cracking characteristics of the influence andthe release of product gas law. The experimental results show that: waste printedcircuit board substrate temperature of the main pyrolysis reaction interval for280℃⁴80℃,with the increase of the heating rate, DTG in the peak value of curve toclose direction, the main reaction temperature narrow interval, the reaction timedecreased; pyrolysis gas main ingredients to contain benzene rings, C=O, C-Ogroups such as the aromatic compounds, still contain CO₂, CO, CH₄and smallmolecules. And then based on the experimental analysis of data hot heavy, Awaste printed circuit board substrate heat cracking dynamics model was solved,using the method of Malek that printed circuit board pyrolysis reactionmechanism function for RO2, waste printed circuit board substrate pyrolysisdynamics mechanism function mechanism function for:f （1-α）=（1-α）²andG （1-α）=（1α）11.Then using PY-GC/MS method, sample in different cracking under theterminal temperature rapid heat cracking, analyzes the different conditions of themain gas cracking products, compares the differences of the product. When600℃three main product phenol,2-phenoxyethanol,2-isopropyl phenol;800℃and1200℃of three main product the same, respectively （Z）-2-（4-methyl ringhas-3-alkenyl） c-1-ene-1-alcohol,2,4,5-three methyl phenol,1,2,3,5-four methylbenzene; One hot cracking condition is different, the heat cracking the finalproduct. The heating rate increase to heat cracking the separation of the product,but the heating rate increase to infinity, the result will be the opposite. With increasing the pyrolysis temperature， the characteristics peak of pyrolysisproducts increase and the main product obtained was correspondingly increased.