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In this study, the performance of several differently treated natural zeolites in a sequential pyrolysis and catalytic reforming of plastic materials i.e. polypropylene (PP) and polystyrene (PS) were investigated. The experiments were carried out on two stage reactor using semi-batch system. The samples were degraded at 500°C in the pyrolysis reactor and then reformed at 450°C in the catalytic reformer. The results show that the mordenite-type natural zeolites could be used as efficient catalysts for the conversion of PP and PS into liquid and gaseous fuel. The treatment of natural zeolites in HCl solution showed an increase of the surface area and the Si/Al ratio while nickel impregnation increased the activity of catalyst. As a result, liquid product was reduced while gaseous product was increased. For PP, the fraction of gasoline (C5-C12) increased in the presence of catalysts. Natural zeolite catalysts could also be used to decrease the heavy oil fraction (>C20). The gaseous products were found that propene was dominated in all conditions. For PS, propane and propene were the main components of gases in the presence of nickel impregnated natural zeolite catalyst. Propene was dominated in pyrolysis over natural zeolite catalyst. The high quality of gaseous product can be used as a fuel either for driving gas engines or for dual-fuel diesel engine.

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This study aims to utilize pyrolysis oil produced from the pyrolysis of waste polyethylene in a direct injection (DI) diesel engine. In this paper, the performance and emission of a diesel engine have been studied using blends of waste polyethylene pyrolysis oil with diesel fuel under different loads condition. The waste polyethylene pyrolysis oil (WPO) used in this work was produced from the sequential pyrolysis and catalytic reforming of polyethylene bag after crushing and washing using natural zeolite (NZ) catalyst. Engine tests have been done using a four-cylinder and four-stroke diesel engine with the compression ratio of 22 and water cooling system. The experimental works were done at the rated engine speed of 1800 rpm. The results indicated that the brake thermal efficiencies are slightly higher as compared to that of diesel while the brake specific fuel consumption (BSFC) is slightly reduced when blending diesel fuel with WPO. Moreover, WPO-diesel fuel blends at various engine loads are also found to have influences on the emissions of CO, HC, NOx, and the smoke opacity. The NOx emission is found to be lowered by blending diesel with WPO. The decreased NOx emission is due to the decrease of the in-cylinder temperature by the effect of the non-homogeneity of WPO. The emissions of HC and CO of WPO-diesel blends are higher than that of diesel. Finally, the smoke opacity for WPO blends is slightly higher at higher loads.

<p>Penelitian ini bertujuan untuk mengetahui karakteristik minyak dan gas hasil proses dekomposisi termal (pirolisis) sampah plastik jenis l<em>ow density polyethylene</em> (LDPE) dengan berbagai variabel laju kenaikan suhu selama proses pirolisis terjadi. Pada proses ini digunakan reaktor pirolisis kapasitas 2 kg dengan laju kenaikan suhu sebesar 2, 4, dan 6 °C/menit sebagai variabel penelitian. Minyak dan gas yang terbentuk ditampung dalam wadah penampung dan diukur rendemennya. Karakteristik gas yang dihasilkan kemudian diuji di laboratorium menggunakan peralatan GC-MS dan peralatan uji sifat fisik khusus untuk minyak hasil pirolisis. Berdasarkan hasil penelitian, didapatkan bahwa semakin tinggi laju kenaikan suhu, minyak yang diahsilkan semakin banyak dan gas semakin sedikit. Rendemen minyak terbesar sebesar 35,83 % dihasilkan pada proses pirolisis dengan laju kenaikan suhu 6 °C/menit, dimana pada saat itu, nilai rendemen gas adalah paling kecil, sebesar 5,83 %. Sementara hasil identifikasi gas, yang paling dominan adalah gas jenis butena, dimana kadarnya semakin kecil seiring dengan laju kenaikan suhu. Kandungan gas butena terbesar sebesar 98% pada laju kenaikan suhu 2 °C/menit. Sementara berdasarkan uji sifat fisik, karakteristik minyak plastik mendekati sifat-sifat bahan bakar minyak, terutama kerosen., sehingga cukup layak apabila dijadikan sebagai bahan bakar alternatif pengganti BBM.</p><p><em>This study aims to determine the characteristics of oil and gas from the thermal decomposition (pyrolysis) process of waste </em><em>low density polyethylene (LDPE) type plastic with various temperature increase rate variables during the pyrolysis process. In this process a 2 kg capacity pyrolysis reactor is used with a temperature increase of 2, 4, and 6 °C/min as the research variable. The oil and gas that is formed is stored in a container and the yield is measured. The characteristics of the gases produced are then tested in the laboratory using GC-MS equipment and special physical property test equipment for pyrolysis oils. Based on the research results, it was found that the higher the rate of temperature rise, the more oil is produced and the less gas. The largest oil yield of 35.83 % was produced in the pyrolysis process with a rate of temperature rise of 6 °C/min, where at that time, the value of the gas yield was the smallest, amounted to 5.83 %. While the gas identification results, the most dominant is the type of butene gas, where the levels get smaller along with the rate of temperature rise. The biggest butene gas content is 98 % at a rate of temperature rise of 2 °C/min. While based on the physical properties test, the characteristics of plastic oil approach the properties of fuel oil, especially kerosene, so it is quite feasible if used as an alternative fuel to substitute fuel.</em></p>

This paper deals with the potential of using sequential pyrolysis and catalytic reforming process in a continuous system for the conversion of polyethylene and polystyrene into liquid and gaseous fuels using the HY-zeolite catalyst for the catalytic reforming of pyrolysis gas generated in a pyrolyzer. The effect of reforming temperature and the weight hourly space velocity on the product yields, liquid and gaseous compositions have been investigated for each feedstock. The experiments were carried out at the pyrolyzer temperature of 450 °C, the reforming temperature of 400, 450, and 500 °C and the weight hourly space velocity of 2, 3, and 4 g-sample g-catalyst -1 h -1 . The results show that increasing the reforming temperature and decreasing the weight hourly space velocity have resulted in an increase of gaseous and solid products while the liquid product decreased. The maximum oil production for HDPE (70.0wt%) and PS (88.1wt%) were obtained at the pyrolysis temperature of 450 °C, the reforming temperature of 450 °C and the weight hourly space velocity of 4. The C2, C3 and C4+ gases (>75 mol %) were the main components of the gaseous and liquid products for HDPE. In case of PS, the C2 and C3 gases (>65 mol %) were the main components of the gaseous product. The high quality of gaseous products can be used as a fuel either for driving gas engines or for dual-fuel diesel engines.