Resumo. The search for cleaner fuels has resulted in the development of research for the processing of fats and oils, composed mainly of fatty acids with high energy and capable of conversion into esters (biodiesel) by transesterification or esterification reactions inhomogeneous catalysis, heterogeneous enzymatic or supercritical. The homogeneous transesterification is the most widely used, however the products obtained concentrated high levels of impurities, why are complemented secondary purification procedures such as liquid-liquid extraction and simple distillation, processes that enhance the generation of waste. The problems identified with the use of transesterification with homogeneous catalysis can be minimized by transesterification with heterogeneous catalysis that seeks to improve the effectiveness of biodiesel production. Thus, studies were conducted with heterogeneous catalysis transesterificationin a laboratory scale reactor, jacketed, with agitation system, temperature controlled and sealed to prevent the diffusion ofreagents to the environment. The heterogeneous catalyst used in these studies was developed by dissolution of potassium hydroxidein water and subsequent impregnation of aqueous solution, formed in clay and subsequent calcination. Thecatalyst was integrated in the reactor and added the necessary reagents for the production of biodiesel. Throughout the execution ofexperiments, controlling the process parameters such as reaction time, temperature and degree of agitation. The products obtainedwere evaluated and calculated the degree of conversion of fat into fatty acid esters and final concentration of esters.