Synthesis and Characterization of Pelletized Coke with Tar Impregnation from Carbonization of Palm Kernel Shells as Nickel Laterite Reductant

The nickel laterite beneficiation policy supports the domestic stainless and alloy steel industries. However, reliance on imported coke for smelting remains a major challenge. The main challenge is the dependence on imports of reductant coke for the smelting process. Palm kernel shell (PKS) is a promising alternative that aligns with the carbon-neutral concept, but its pyrolyzed carbon shows low calorific value and mechanical strength for metallurgical use. This study aims to produce biocoke by converting PKS into carbon–carbon (C/C) composites using its carbon and tar products to enhance mechanical and thermoplastic properties. This study aims to produce biocoke by converting PKS into carbon–carbon (C/C) composites using its carbon and tar products to enhance mechanical and thermoplastic properties. Initial KOH activation (impregnation mass ratio 0.5) created a porous structure for tar deposition. Briquetting (30×30 mm) followed by co-carbonization (250 °C, 1 h) was conducted at various char-to-tar mass ratios. The best condition was achieved at a tar ratio of 1:2, producing composites with high fixed carbon (88.17%), low volatile matter, and compressive strength suitable for metallurgical applications. SEM analysis confirmed uniform carbon fiber distribution within the matrix. The final product also met ASTM D3173 standards with a heating value of 7,328 kcal/kg. XRD analysis of limonite ore reduction using this biocoke showed a decrease in geothite and lizardite phases and the formation of metallic phases such as Fe-Ni alloy, FeS, and wustite, especially at 900 °C and 1100 °C. These results indicate effective metallothermic reduction. C/C composite from PKS offers a sustainable, high-performance alternative to commercial coke for nickel laterite reduction, fulfilling both energy and environmental considerations.