wet process phosphoric acid solution formed from uncalcined phosphate rocks generally contains about 600 grams/liter of H3 PO4, about 0.2 gram/liter of uranium, about 1 gram/liter of calcium, about 9 grams/liter of iron, about 28 grams/liter of sulfate and about 30 grams/liter of fluorine. The phosphoric acid solution also contains varying amounts of arsenic, magnesium, aluminum, and humic acid impurities.