This study develops an eco-friendly sol-gel method to extract high-purity silica from black rice husk ash (BRHA), rich in silica but limited by residual carbon. BRHA is treated with NaOH to form sodium silicate, followed by HCl precipitation to obtain silica gel. The effects of BRHA amount, HCl volume, and pH on yield and purity are optimized. Characterization (XRD, SEM, XRF, PSA) confirms the process’s efficiency in producing sustainable silica and carbon materials.