the use of enhanced surface hydrophobization [16].
Numerous research studies involving sulfonated carbon catalysts
have reported that the optimum sulfonation temperature
strongly depends on the type of carbon and its source [25e27]. The
research reported here explored the synthesis of sulfonated activated
carbon catalysts derived from coffee residue (SCAC) for
esterification. Preparation included the use of enhanced surface
hydrophobization. Esterification of caprylic acid was used to evaluate
catalytic performance.