Reactions of Ammonium Polyphosphates with Soil Minerals

Abstract

Abstract When suspended in solutions of ammonium pyro‐ or tripoly‐phosphates at room temperature, calcium and magnesium carbonates reacted rapidly and clay minerals and hydrous oxides of iron and aluminum reacted slowly. The precipitated solid products of the reactions included calcium and magnesium ammonium pyro‐ and tripolyphosphates and iron and aluminum ammonium pyrophosphates but no tripolyphosphates; no solid orthophosphates were formed. The condensed phosphates were much less reactive with the soil minerals than are orthophosphates.