The effect of sodium sulfate (Na2SO4) and sodium carbonate (Na2CO3) addition on the reduction-roasting process of titania iron sandAgung Nugraha, Bambang Priyono, Ahmad Maksum, Haidir Juna and Johny Wahyuadi SoedarsonoE3S Web Conf., 67 (2018) 03054DOI: https://doi.org/10.1051/e3sconf/20186703054