Phosphate Fertilizers by Calcination Process - Action of Silica and Water Vapor on Phosphate Rock

Abstract

Bull., to be published (contains bibliography).

Phosphate Fertilizers by Calcination Process Factors Affecting the Reaction between Water Vapor and Florida Land-Pebble Phosphate

“…Phosphates In confirmation of the data given in a previous paper (8), the results given in this paper shoiv that no significant increase in the citrate solubility of the phosphorus occurred until all of the fluorine in excess of that corresponding to one atom of fluorine (F's) in the fluorapatite equivalent of the total phosphorus was volatilized. From that point the citrate solubility of the phosphorus corresponded approximately to the percentage of F's volatilized, provided the temperature of the experiment exceeded 1300°C.…”

The Basic Calcium Phosphates and Related Systems. Some Theoretical and Practical Aspects.

“…The major problems are (a) how to remove fluorine, as the presence of fluorine has a marked effect in rendering phosphatic materials unavailable (4,5,10,25,104,120,134,180); (b) how to prevent or minimize the formation of hydroxyapatite through reaction with atmospheric moisture during cooling; (c) how to prevent or minimize the transformation of a-tricalcium phosphate to the less soluble (3-tricalcium phosphate during cooling. The Bureau of Chemistry and Soils of the United States Department of Agriculture made a systematic effort to solve these problems, and the results are contained in a series of papers which are remarkable for their thoroughness and soundness (95,142,166,167,168).…”

Fertilizer from Rock Phosphate Conversion by Fusion and Treatment with water Vapor

“…Jacob and his co-workers in the United States Bureau of Chemistry and Soils studied this process on a small scale (3,4,5,6).…”