The phosphoric acid (PA) industry is essential for global food security, but it generates toxic and challenging wastewater (WW) of environmental concern. PA is the primary P source of the chemical fertilizer industry . With an estimated 46 million tonnes (Mt) of global demand in 2019/20 and steady growth of P output, global PA fertilizer production is expected to reach ~52.5 Mt in 2025/26 . PA is currently produced mainly by the "wet process" utilizing concentrated H2SO4 to dissolve phosphate ore comprising mainly hydroxy/fluor-apatite . Large volumes of water are required to facilitate the dissolution reaction and other tasks such as slurry transport, washing, and hydraulic pressurization .