Reduction of P2O5 and F from Phosphogypsum by CaO addition Sri Rachmania Juliastuti, Nuniek Hendrianie, Yumna Dian Pawitra and Irham Raditya Putra MATEC Web Conf., 156 (2018) 03021 Published online: 14 March 2018 DOI: 10.1051/matecconf/201815603021