Modifikasi Zeolit HZSM-5 Terimpregnasi Logam Nikel dan Carbon Nanotube sebagai Katalis dalam Proses Hydrocracking Crude Palm Oil untuk Produksi Biofuel

Abstract

This study aims to enhance the catalytic performance of HZSM-5 zeolite by incorporating nickel (Ni) via impregnation and adding carbon nanotube (CNT) for the conversion of crude palm oil (CPO) into biofuel. Three catalysts HZSM-5, Ni-HZSM-5, and CNT/Ni-HZSM-5 were synthesized and characterized using XRD, SEM-EDX, TEM, NH₃-TPD, BET, and TGA to assess their crystallinity, morphology, acidity, surface area, and thermal stability. The conversion process involved two stages: esterification and transesterification as pretreatment, followed by hydrocracking at 500 °C for 2 hours. The results showed that acidity increased from 2.31 mmol/g (HZSM-5) to 2.81 mmol/g (Ni-HZSM-5), while surface area improved significantly from 76.58 m²/g to 272.83 m²/g with the addition of CNTs. The CNT/Ni-HZSM-5 catalyst exhibited the highest biofuel conversion (80.4%), followed by Ni-HZSM-5 (68.8%) and HZSM-5 (66.6%). GC-MS analysis indicated that all three catalysts were more selective towards the biodiesel fraction. The resulting biofuels exhibited viscosities of 1.3278–1.36 cP and densities ranging from 0.8095 to 0.8286 g/cm³, with hydrocarbon chains predominantly in the C8–C19 range. These findings confirm that the synergistic modification of HZSM-5 with Ni and CNTs significantly enhances both the conversion efficiency and fuel quality of CPO-derived biofuel.