Pyrolysis of e-waste for oil production

Abstract

Electronic waste is one of the fastest growing waste streams in Uganda and apparently there is no well-established procedure of dealing with this waste. If not well disposed off, this waste is nonbiodegradable and can be highly toxic especially if openly dumped or landfilled. On the other hand, a large portion of E-waste contains plastics, in addition to some metal elements that could be recovered with appropriate technology. The main objective of this study was to investigate the viability and efficiency of pyrolysis of e-waste in volume reduction and fuel recovery from plastics. The study was conducted at Makerere University Agricultural Research Institute Kabanyolo and at the Chemistry Research Makerere University Laboratory. Pyrolysis was carried out in a batch reactor, for every batch, 250 g of e-waste was pyrolysed under temperature regimes of 150 ºC, 300 ºC and 400 oC with retention times of 60, 90 and 120 minutes. The fuel was collected over water, as it is less dense than water while char was collected by emptying the remains in the reactor. . Fractional distillation was used to characterize and separate the different components of the liquid fuel. The quantity and quality of fuel collected depended entirely on the temperature and residence time. Liquid yields ranging from 21.12- 81.88 % and char content of 14.4-76.8 wt.% were obtained. Highest char content of 76.8 wt.% was obtained at temperature 150 oC and retention time of 60 minutes whereas the highest fuel yield was obtained at temperature 300 oC at a retention time of 120 minutes. The liquid fuel had densities of 0.880-g/cm3, 0.887-g/cm3and 0.776-g/cm3 Upon distillation it was found that the fuel oil on average contained 14.06 wt.% naphthalene, 13.3 wt.% diesel and 33.6 wt.% gasoline. The solid volume reduction was achieved as the masses decomposed making pyrolysis a better option for waste management.