Phosphogypsum Two-Step Ammonia-Carbonation …
Phosphogypsum Two-Step Ammonia-Carbonation Resulting in Ammonium Sulfate and Calcium Carbonate Synthesis: Effect of the Molar Ratio OH−/Ca2+ on the Conversion …
Effect of maleic acid and pH on the preparation of α-calcium sulfate …
Phosphogypsum (PG) is a by-product of the wet-process phosphoric acid process, which causes serious environmental issues. In this work, PG was taken as raw material to …
Process Optimization and Mechanism Study for Sulfur
More than 97.44 wt % of sulfur could be recovered with a C/S molar ratio of 0.5–0.8 at 1300 °C or above in the molten state, and the molten slag was an amorphous …
Role of polyacrylamide in the removal of soluble phosphorus …
Phosphogypsum, an industrial solid waste produced in wet phosphoric acid production, is difficult to be utilized due to the harmful impurities such as phosphorus and …
A Novel Process to Recover Gypsum from Phosphogypsum
In this study, we investigated a coarse phosphogypsum containing 49.63% SO3, 41.41% CaO, 10.68%, 4.47% SiO2, 1.28% P2O5, 0.11% F, CaSO4·2H2O purity of 80.65%, and whiteness …
Studying the Process of Phosphogypsum …
Phosphogypsum is a product formed during the decomposition of raw phosphate materials with sulfuric acid using an extraction method. As a rule, extraction of phosphorus from raw materials is carried out with mineral acids …
Sustainable Approach for Recovery of Sulfur from …
It also shows that the thermochemical decomposition of calcium sulfate is not complete and that the sulfur present in the residue exists in the form of sulfate and calcium …
Preparation of Anhydrous Calcium Sulfate Whiskers from Phosphogypsum …
The anhydrous calcium sulfate (AH) whiskers were prepared in H 2 O-H 2 SO 4 autoclave-free hydrothermal system by using phosphogyp- sum (PG) as raw materials. The …
Utilization of phosphogypsum for the preparation of …
Utilization of phosphogypsum for the preparation of α-calcium sulfate hemihydrate in chloride-free solution under atmospheric pressure. Yang Mi, . School of Materials Science …
Utilization of phosphogypsum for the preparation of α‐calcium sulfate …
Utilization of phosphogypsum for the preparation of α-calcium sulfate hemihydrate in chloride-free solution under atmospheric pressure. Yang Mi, . School of Materials Science …
Recovery of Sulfur From Phosphogypsum: Conversion …
The first step in the conversion scheme involves reduction of phosphogypsum to calcium sulfide. Effects of temperature, catalyst, reaction time, and type of reductant (carbon monoxide and
Recovery of sulfur from phosphogypsum: conversion of calcium sulfate …
The experiments carried out in this investigation have enabled us to recover sulfur in the form of SO2 using appropriate additives such as silica, alumina, clay, and charcoal as reducing agents …
Recovery of Sulfur From Phosphogypsum: Conversion of …
The first step in the conversion scheme involves reduction of phosphogypsum to calcium sulfide. Effects of temperature, catalyst, reaction time, and type of reductant (carbon monoxide and
Energy conservation and carbon emission reduction of cold …
It employs phosphogypsum as its primary base material and incorporates additives such as cement, water, and a curing agent. Phosphogypsum, sourced from chemical plant …
Preparation of α-Calcium Sulfate Hemihydrate by Reaction …
Direct preparation of α-calcium sulfate hemihydrate out of sulfuric acid solution by reaction with lime under atmospheric pressure conditions is systematically investigated. Two …
Utilization of phosphogypsum for the preparation of α-calcium sulfate …
BACKGROUND This work aims to investigate the possibility of recycling by‐product phosphogypsum (PG) as raw material for preparing α‐calcium sulfate hemihydrate (α‐CSH) in …
Utilization of phosphogypsum for the preparation of …
This work aims to investigate the possibility of recycling by-product phosphogypsum (PG) as raw material for preparing α-calcium sulfate hemihydrate (α-CSH) in chloride-free salt …
Utilization of phosphogypsum for the preparation of α‐calcium sulfate …
This work aims to investigate the possibility of recycling by-product phosphogypsum (PG) as raw material for preparing α-calcium sulfate hemihydrate (α-CSH) in chloride-free salt …
Sustainable Approach for Recovery of Sulfur from …
It seems that bentonite clay is an adjuvant that promotes, in a remarkable way, the decomposition of calcium sulfate. It follows from these tests that, through appropriate …
Studying the Process of Phosphogypsum Recycling into a Calcium …
Phosphogypsum is a product formed during the decomposition of raw phosphate materials with sulfuric acid using an extraction method. As a rule, extraction of phosphorus …
Recovery of calcium and sulphur from phosphogypsum with …
The lab-scale preparative vertical-flow electrophoresis (PVFE) system with supporting media achieved successful recovery of calcium and sulphur from phosphogypsum …
Gradient removal of Si and P impurities from phosphogypsum …
Phosphogypsum (PG) is a solid waste generated during the production of wet -process phosphoric acid.The silicon and phosphorus impurities in PG greatly affect its …
Recovery of CaO from CaSO4 via CO reduction
Calcium sulfate dihydrate was used as a model compound for gypsum; it was mixed with solid carbon and heated to a terminal temperature of 1100 degrees C. CaO was produced …
Recovery of Sulfur From Phosphogypsum: Conversion …
RECOVERY OF SULFUR FROM PHOSPHOGYPSUM: CONVERSION OF CALCIUM SULFATE TO CALCIUM SULFIDE By Margaret M. Ragin 1 and Donald R. Brooks2 ABSTRACT In a …
Process Optimization and Mechanism Study for …
More than 97.44 wt % of sulfur could be recovered with a C/S molar ratio of 0.5–0.8 at 1300 °C or above in the molten state, and the molten slag was an amorphous magnesium–calcium–aluminosilicate. The PGI desulfurization …
A novel method for purification of phosphogypsum
Nearly 90% calcium was converted into calcium sulfate dihydrate (CaSO4·2H2O) in about 15 min, and after impurity separation the CaSO4·2H2O with about 90% whiteness …
Study on hydration kinetics and characteristics of high …
The predominant chemical constituent of PG is calcium sulfate dihydrate (CaSO 4 ·2H 2 O), accompanied by minor impurities such as fluorine, phosphorus ... A novel and …
Recovery of sulfur from phosphogypsum: conversion of …
The experiments carried out in this investigation have enabled us to recover sulfur in the form of SO2 using appropriate additives such as silica, alumina, clay, and charcoal as reducing agents …
Recovery of calcium and sulphur from phosphogypsum …
The lab-scale preparative vertical-flow electrophoresis (PVFE) system with supporting media achieved successful recovery of calcium and sulphur from phosphogypsum …
(PDF) Conversion of phosphogypsum to sodium sulfate and calcium …
For the Moroccan phosphogypsum, [12] and [13] presented a heterogenous composition of PG which consists mainly of calcium sulfate both dihydrate and hemihydrate …
Effect of CO partial pressure on phosphogypsum …
Phosphogypsum (PG) is a byproduct of phosphoric acid production and consists mainly of calcium sulfate (CaSO4). PG management is a critical concern in the phosphoric …