Adsorption purification of waste water from chromium by ferrite manganeseLiliia Frolova, Mykola Kharytonov, Iryna Klimkina, Oleksandr Kovrov and Andrii KoveriaE3S Web Conf., 168 (2020) 00026DOI: https://doi.org/10.1051/e3sconf/202016800026