Product characterization of waste printed circuit board by pyrolysis

This paper is part of a project which Studies pyrolysis as an alternative for recycling printed Circuit board (PCB); the sample (2.0 cm x 2.0 cm) was pyrolyzed under nitrogen atmosphere, at 300, 400, 500, 600 and 700 degrees C in a tubular type Oven, Maintaining 30 min, and during the pyrolysis process the organic part is decomposed to pyro-oils and pyro-gases, which can be used as fuels or chemical material resources: the solid residues of about 75-80 wt%, liquid yields of similar to 9.0 wt.% and gas yields of 12-14 wt.%. No significant influence of temperature was observed over 500 degrees C, however, there was certainly influence under 500 degrees C in both volatile Substance. The pyro-oils have fairly high gross Calorific Values (similar to 30 kJ/kg), mainly with aromatic and with oxygenated compounds. The pyro-gas is very rich in CO. CO2, H-2, CH4 and in small part of O-2; after being purged it can be combusted for the pyrolysis self-sustain. The tensile strength decreases about 35% at 773 K, while the impact and tear strength increases above 773 K, and then decreases along with the temperature increase. The strength changes can offer guidance for used as a replacement for virgin fibres in SMC manufacture. The residues are better laminated can be easily liberated for metals recovery. (c) 2008 Elsevier B.V. All rights reserved.