PREPARATION AND CHARACTERIZATION OF BENTONITE CLAY CATALYSTS FOR TRANSESTERIFICATION OF WASTE COOKING OIL INTO BIODIESEL. FJS [Internet]. 2024 Apr. 30 [cited 2025 Sep. 4];8(2):204-11. Available from: https://fjs.fudutsinma.edu.ng/index.php/fjs/article/view/2347