Bentonite has been modified using H2SO4 at various concentrations to alter Si/Al ratio that is responsible for catalytic pyrolysis of single-use waste polyethylene (SUWP). The XRF analysis confirmed a gradual decrease of Al2O3 content with an increasing concentration of H2SO4. The highest liquid hydrocarbon yield (87.48%) was obtained at Si/Al ratio of 34.24. To further activate acid-modified bentonite, bimetals (Cu/Ni, Fe/Ni, and Co/Ni) impregnation was conducted. The catalytic performance was compared with monometals (Ru, Co, Ni, Cu, and Fe) impregnated bentonite counterparts. The Co, Ni, or Cu impregnated bentonite catalysts (with 86, 83, and 86% yield) outperformed Fe and Ru impregnated bentonite catalysts (with 68% and 79% yield). However, bimetallic (Cu/Ni, Fe/Ni and Co/Ni) catalysts enhanced severe cracking leading to the formation of more gaseous hydrocarbons and thus less amount of liquid (70–80%) is obtained. Incorporation of iron into bentonite or Ni/bentonite increased the amount of 2-Octene, 3,7-dimethyl-, (Z)- compared to acid-treated bentonite and Ni/ bentonite catalysts. Moreover, Fe/Ni/bentonite has also increased the amount of 2-Octene, 2,6-dimethyl- compounds. The BET analysis shows that both surface area and pore diameter increased due to acid treatment resulting in an increase in the percent yield of liquid compared to raw bentonite. The FTIR and GC-MS analysis confirmed that the liquid hydrocarbon consists of linear and branched alkanes and alkenes with some cyclic hydrocarbons. The NMR analysis showed the liquid hydrocarbon is free from the aromatic compounds and polycyclic aromatic hydrocarbons (PAH).

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