Resumen de Using discarded oyster shells to obtain biodiesel
Miguelina De la Cruz De la Cruz, Patricia de la Cruz Burelo, Emanuel Hernández Núñez, Ramón Eduardo Santiago González, Cintya Valerio Cárdenas, Víctor Manuel Villegas Cornelio
ABSTR ACT Objective: To evaluate the CaO made from oyster shell (C. virginica) as a heterogeneous catalyst in the transesterification of edible vegetable oil used for the production of biodiesel.
Design/methodology/approach: A completely randomized experimental design was used, which grouped 3 treatments with 3 repetitions, generating a total of 9 experimental units. The response variable was the performance of the transesterification reaction that was evaluated with 2%, 3% and 4% of CaO obtained from oyster shells. The density, kinematic viscosity, acidity, and conversion efficiency to methyl esters were determined by 1H NMR of the products of each treatment.
Results: The treatment with 3% catalyst showed the highest reaction yield (92.2%) compared to the treatments with 2% (86.8%) and 4% catalyst (87.13%). The 1H NMR spectra confirmed the presence of methyl esters in the product of the three treatments. The treatment with 3% and 4% by weight of catalyst presented products with similar characteristics with acceptable values of density, viscosity and acid number in accordance with the ASTM D6751 and EN1421 standards.
Study limitations/implications: A concentration of 2% by weight of CaO generates a conversion percentage far from the content of methyl esters established by the ASTM D6751 and EN14214 Standards (96.5%).
Findings/conclusions: 1H NMR results indicate that the conversion efficiency to methyl esters is positively affected by the amount of catalyst. In the treatments with catalyst loading greater than 2%, the conversion to methyl esters increased significantly to values around 90%.
