Preparation of iron catalysts supported in biomass arising from the coconut green shell for the falling of methylene blue. Int. J. Geosci., Eng. Technol. [Internet]. 2021 Apr. 30 [cited 2026 Apr. 22];3(1):1-5. Available from: https://revistas.apps-teste.ufvjm.edu.br/index.php/ijget/article/view/427