Abstract :

Pyrolysis with or without the aid of catalyst have attracted much attention for the conversion of waste plastics to their monomers or partially de-polymerized oligomers. The resulting monomers can be recycled to the original or related polymeric product as well as gasoline range products.  In this work, the pyrolysis of contaminated Low Density Polyethylene (LDPE) was done both thermally and catalytically. The gases from each sample were collected in Tedlar bags and analysis was done using a Buck 530 Gas chromatograph. Results from the thermal pyrolysis  showed aliphatic hydrocarbons within the range of C₁ – C₉ with a total concentration of 36.0906 ppm and 64.5041 ppm for gases collected at 200 ºC and 350 ºC  respectively. The pyrolysis was also repeated under the influence of zeolite catalyst using catalyst/sample ratios of 1:8 and 1:16 at 150 ºC and 250 ºC. Results revealed total yield of gases for LDPE under the zeolitic effect of temperatures of 150 ºC and 250 ºC using catalyst/sample ratio of 1:8 to be 721.0371 ppm and 835.0906 ppm. The corresponding values obtained at 150 ºC and 250 ºC using catalyst/sample ratio of 1:16 were 697.4464 ppm and 713.7277 ppm respectively. The hydrocarbon gases revealed mainly C₁– C₁₀ aliphatic hydrocarbons. These when fractionated can result into combustible gases and gasoline range product.

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Keywords :

combustible gases, low density polyethylene, Pyrolysis, zeolite.

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