Development and Characterization of Sustainable Coal–Biomass Briquettes of Sub‐Bituminous Coal and Levistona chinensis Biomass

The increasing demand for sustainable energy solutions has driven the exploration of alternative fuels, such as coal–biomass briquettes, which combine the benefits of both coal and renewable biomass sources. This study focuses on the development and characterization of sustainable coal–biomass briquettes made from sub‐bituminous coal (SubC) and Levistona chinensis seed biomass, with the aim of reducing environmental impact and enhancing combustion properties. Briquettes were produced by varying the coal‐to‐biomass ratios (90:0–0:90), with 10% corn starch used as a binder. Proximate analysis revealed that increasing biomass content raised moisture (5.85%–14.25%) and volatile matter (VM; 24.75%–32.5%), while reducing ash (15.75%–3.39%) and fixed carbon (FC; 53.71%–48.86%). Ultimate analysis showed decreases in carbon (65.80%–41.95%) and sulfur (3.40%–0.62%), indicating lower pollutant emissions. Calorific value declined from 25.54 MJ/kg (with higher coal content of 90%) to 19.01 MJ/kg (with higher biomass of 90%). Heavy metal analysis revealed significant reductions in lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) levels (20.91, 1.016, 9.14, and 19.067 mg/kg to undetectable), enhancing environmental safety. Micronutrient analysis showed an increase in potassium (0.214–6.026 mg/kg) and a decrease in iron (Fe; 160.39–0.292 mg/kg), suggesting ash could benefit agriculture. Briquette density decreased from 1.327 to 1.212 g/cm 3 , falling within the optimal handling range. The study demonstrates coal–biomass briquettes as a viable, eco‐friendly alternative for sustainable energy applications.