Reducing settling rate of post-precipitate in fertilizer solution by chloride addition
AssigneeMississippi Chemical Corporation
InventorCharles W. Weston
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Abstract
Precipitate settling in ammonium polyphosphate liquid fertilizer solutions containing magnesium, iron, aluminum compound impurities, prepared by concentrating and ammoniating wet process orthophosphoric acid, is impeded by addition to the ammonium polyphosphate, prior to precipitate formation, a source of Cl.sup.- in amounts sufficient to alter the morphology of the precipitate crystals such that the length-to-width ratio of the crystals formed is increased by at least 200%, as compared to the ratio for crystals formed in the absence of Cl.sup.- addition. Since there is little propensity for the longer and thinner crystals to settle out of solution, the crystals remain innocuously suspended in the solution.
Claims15
A method of impeding the formation and the settling of precipitate crystals in liquid ammonium polyphosphate containing fertilizer solutions prepared by concentrating and ammoniating wet process phosphoric acid which comprises adding within 120 hours of completing the preparation of said ammonium polyphosphate containing solution a quantity of chloride ions to the liquid fertilizer solution in amounts sufficient to alter the morphology of the precipitate crystals such that the length to width ratio of the crystals formed is increased by at least 200% as compared to the ratio for crystals formed in the absence of Cl.sup.- addition.
Dependencies are inferred from the claim text.