Bentonite is commonly used as a bleaching earth to purify crude palm oil, but its adsorption capacity needs to be improved. This innovation combines bentonite with hydrochar, which is processed from cassava’s peel, to produce composite for palm oil bleaching. Pyrolysis or thermal decomposition in the absence of oxygen, is used to convert biomass into hydrochar and activate bentonite. The addition of hydrochar can increase the adsorption capacity of bleaching earth, and it also faster the palm oil bleaching process.