Precipitation of impurities in 9-32-0 grade fluid fertilizers
For several years TVA has been studying production of 9-32-0 ammonium polyphosphate suspension produced from ammoniated merchant-grade wet-process orthophosphoric acid. Suspensions containing polyphosphate have an advantage over those that contain only orthophosphate in that they can be stored satisfactorily at much lower temperature. However, the introduction of polyphosphate (pyrophosphate anion) complicates the precipitation of impurities and has yielded inconsistent storage characteristics in 9-32-0 fluid fertilizers. Fluorine also has been shown to affect suspension fertilizer properties. The viscosity of 13-38-0 orthophosphate suspension fertilizers is affected by the atomic ratios F:(Al + Fe + Mg). Addition of fluorine prevents sludges and precipitates in ammonium polyphosphate fertilizer solutions - the proper amount of fluorine is related to the amount of each of the metallic impurities present and also to the fraction of the phosphate present as pyrophosphate. Incorporation of polyphosphate or fluorine or both has been shown to have positive effects on ammoniated wet-process phosphoric acid (WPPA), but they do not report the solubility relationships of the cation impurities (Fe, Al, Mg, and Ca) with respect to the anion constituents (PO/sub 4/, P/sub 2/O/sub 7/, and F). Therefore, a factorial study was developed to determine the solubility relationships of the precipitated metal impurities encountered in 9-32-0 fluid fertilizers. 10 refs., 1 fig., 20 tabs.
- Research Organization:
- Tennessee Valley Authority, Muscle Shoals, AL (USA). Office of Agricultural and Chemical Development
- OSTI ID:
- 6071026
- Report Number(s):
- TVA/OACD-86/6; ON: DE86901143
- Resource Relation:
- Other Information: Portions of this document are illegible in microfiche products. Bulletin Y-194
- Country of Publication:
- United States
- Language:
- English
Similar Records
Polyphosphate-containing fluid fertilizers based on wet-process acid and wet-process acid-sulfuric acid mixtures
Production of high-quality liquid fertilizers from wet-process acid via urea phosphate
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
AMMONIUM PHOSPHATES
IMPURITIES
FERTILIZERS
CHEMICAL COMPOSITION
PRECIPITATION
CHEMICAL PREPARATION
EXPERIMENTAL DATA
FLUORINE
VISCOSITY
AMMONIUM COMPOUNDS
DATA
ELEMENTS
HALOGENS
INFORMATION
NONMETALS
NUMERICAL DATA
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
SEPARATION PROCESSES
SYNTHESIS
400201* - Chemical & Physicochemical Properties