Ngoc Tu Nguyen, Quang Huy Trinh, Thi Thu Ha Nguyen, Van Duc Tran and Thi Thuy Hang Ho 2023. Study on the modification of fly ash as a coagulant. Vietnam Journal of Science, Technology and Engineering. 65, 2 (Jun. 2023), 20-25. DOI:https://doi.org/10.31276/VJSTE.65(2).20-25.