Transesterification of Persea americana seed oil to methyl ester using bio-based heterogeneous catalyst: Optimization and techno-economic analysis oleh Okwudili E. Umeagukwu, Dominic O. Onukwuli, Callistus N. Ude, Chizoo Esonye, Benjamin Nnamdi Ekwueme, Christian O. Asadu, Faith C. Okey-Onyesolu, Mbabuike U. Ikenna, Ekuma Innocent Chukwudi, Trobjon Makhkamov, Sokhib Islamov, Imomova Mukammal Yormukhamatovna