Purification Of Phosphoric Acid Research Articles

金属抽出におけるリン酸アルキルの役割 （第１報） リン酸アルキルの精製法とその物性

The investigation and experiments were carried out on purification of butyl phosphoric acid, 2-ethylhexyl phosphoric acid and 2-ethyloctyl phosphoric acid. Chemical properties of alkyl phosphoric acids purified by this method were measured, which were distribution ratio between oragnic and aqueous phases, acid dissociation constant and interfacial tension.The distribution ratio of mono-esters is much lower than that of the corresponding di-esters. Values of the distribution ratio are 5.2, 49 and 570 for butyl, 2-ethylhexyl and 2-ethyloctyl phosphoric acids, respectively. The mono-esters are fairly strong acids whose dissociation constants are 10-2.1, 10-2.3 and 10-2.3 for butyl, 2-ethylhexyl and 2-ethyloctyl phosphoric acids, respectively. The mono-esters are more surface active comparedwith the corresponding di-esters, except butyl phosphoric acid which has high solubility in an aqueous solution. The interface coverage of mono-esters is calculated from interfacial tension measurements according to Gibbs' equation.

QUATERNARY LIQUID EQULIBRIUM : WATER—PHOSPHORIC ACID—1— PENTANONE AT 25° C.

ABSTRACT Liquid-liquid equilibrium, solubility and tie-line data, for the quaternary system Water-Phosphoric Acid-l-Pentanol-3-Pentanone, were obtained at 25°C and atmospheric pressure, using an analytical method. 1-Pentanol appears to be more effective than 3-Pentanone as extractant solvent of phosphoric acid. Advantages are not observed with the use of mixed solvents in the purification of wet process phosphoric acid by means of solvent extraction.

PURIFICATION OF WET PROCESS PHOSPHORIC ACID BY SOLVENT EXTRACTION WITH PROPYL ETHERS.

ABSTRACT The distribution data for the impurities (SO= 4, F−, Fe, Al and Mg) during purification of wet phosphoric acid (WPA) with di-n-propy1 ether (DPE), di-n-propy1 ether containing 6. 5% of the isomer n-propylriso-propyl ether (DPE(M)) and di-iso-propyl ether (DIPE) at 25°C are reported. The distribution of phosphoric acid (PA)(SO= 4, F−, Fe, Al and Mg between the conjugated phases has been investigated. The system W-WPA-DIPE shows a three-liquid-phases-at-equilibrium zone with 65.7% of phosphoric acid in the aqueous phase, 43.9% in the heavy organic phase and 4.3% in the light organic phase. The degree of purification increases, for the three solvents studied, when decreasing the PA concentration in the organic phase (except for F−when using DPE}. Purification data for iso-arayl alcohol (1) and these three solvents are compared, showing that di-n-propyl ether with 6.5% of the isomer propyl-iso-propyl ether is the best solvent (from all solvents investigated in these series) for the purification of th...

The Recovery of Uranium during the Purification of Phosphoric Acid by Organic Solvents

When wet process phosphoric acid is purified by extraction with isobutanol, sec-butanol, or tributyl phosphate (TBP), the raffinate is enriched in the impurities. Uranium can be recovered from the raffinate by precipitation with ammonia. An upgraded precipitate can be obtained if the bulk of impurities is first crystallized at 200/sup 0/C. sec-Butanol is a more effective extractant than isobutanol and TBP.

4369168 Regeneration of carbon employed in the wet process production of alkali metal phosphates

In a process for regenerating the activated carbon and in the purification of brown phosphoric acid or alkali phosphates obtained via the so-called wet process employing mineral acid digestion of crushed phosphate rock, the activated carbon used to filter brown H3 PO4 is removed from service, washed with water, the initial washings being recovered to reclaim phosphoric acid, and then steeped in a basic aqueous solution, e.g., aqueous alkali hydroxide, alkali carbonate, ammonium hydroxide, loweralkyl amines or loweralkanol amines. After again water washing the activated carbon, to remove residual base, the activated carbon is either returned to service or steeped in an aqueous solution of mineral acid, e.g., sulfuric, hydrochloric, or nitric acid, again washed with water to remove residual acid and returned to service. Usually, the acid steep need not be employed with every base cycle to maintain good decolorization, although if desired the acid steep can be used with each caustic cycle.

31179 Method of processing waste sludge from wet phosphoric acid purification facilities : Peter Muerer; Martin Hater; Fritz Meininghaus; Rudige Scheel; assigned to Uhde GmbH

31179 Method of processing waste sludge from wet phosphoric acid purification facilities : Peter Muerer; Martin Hater; Fritz Meininghaus; Rudige Scheel; assigned to Uhde GmbH

Purification of phosphoric acid with methanol and ammonia

Purification of phosphoric acid with methanol and ammonia

Liquid-liquid techniques in phosphorus chemistry

Abstract

Purification of phosphoric acid with methanol and ammonia

Purification of phosphoric acid with methanol and ammonia

Neure Entwicklungen auf dem Gebiet der Herstellung und Anwendung anorganischer Phosphorprodukte

Abstract

Liquid-Liquid Equilibria of the System Phosphoric Acid-Water-Diethyl Ketone

To obtain the fundamental data of the purification of phosphoric acid through solvent extraction, solubility curve and tie-lines were determined for the system phosphoric acid-water-diethyl ketone at 25°C.The acid concentration at plait point was obtained from extrapolation of the following correlation line : log yA : (xA-yA) /yAwhere yA is acid concentration (wt %) in organic phase and xA is acid concentration (wt %) in water phase.The equilibrium concentration ratio of the acid xA/yA is always larger than unity for all concentration ranges.

The Purification of Phosphoric Acid by Crystallization.

The Purification of Phosphoric Acid by Crystallization.