A novel approach is presented to capture some of the toxic gases emitted during the heat treatment of e-waste using alumina adsorbents. Waste PCBs from mobile phones were powdered to sizes less than 1 mm; their thermal degradation was investigated using thermo-gravimetric analysis. Observed weight loss was attributed to the degradation of polymers and the vaporization of organic constituents and volatile metals. An alumina adsorbent was kept next to PCB powders in a quartz tube to capture these gaseous constituents, and heated to 600 °C with air, nitrogen and argon as carrier gases for times ranging between 10 and 30 minutes. Weight gains up to ~17% were recorded representing significant amounts of particulates captured by the adsorbent. SEM/EDS results on the adsorbent showed the presence of Cu, Pb, Si, Mg and C; these were supplemented by ICP-OES analysis to determine the extent of various species captured as a function of operating parameters. This innovative approach is expected to reduce emissions during waste recycling towards environmentally safe limits.
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