Abstract

Abstract Engineering the wettability of functional materials holds significant interest, focusing on the need for superhydrophobic catalysts, crucial for their ability to prevent the poisoning of active sites by water, produced in situ or as a by‐product. Herein, for the first time, a superhydrophobic spherical activated carbon (SSAC@PhSO 3 H) is engineered as a catalyst via a novel synthetic approach and tailored in Jatropha curcas oil (JCO) biodiesel synthesis. With a large surface area (1461 m 2 g −1 ), high acid density (6.26 mmol g −1 ), and water contact angle (163.4°), the catalyst demonstrates superior performance and remarkable water repellency, firmly establishing its superhydrophobic characteristics. Response Surface Methodology based on the Central Composite Design (RSM‐CCD) approach predicted a maximal biodiesel yield of 98.8% (80 °C, 5 wt%, 15:1 methanol to oil molar ratio (MOMR), and 40 min). Life cycle cost analysis (LCCA) estimates biodiesel production cost of 0.37 USD ($) per kg emphasizing high commercial viability. Compared with H 2 SO 4 ‐sulfonated biochar, SSAC@PhSO 3 H retains its inherent activity (86.8 ± 0.4% yield in 10 th run) and spherical morphology even after nine successive reaction cycles indicating high stability. Nevertheless, JCO biodiesel's fuel properties met European Norm, EN 14 212 and American Society for Testing and Materials, ASTM D6757 standards, highlighting its potential for industrial biodiesel production.