Identification and Quantification of the Organic Matter in the Fouling Industrial of Wet Phosphoric Acid Process

Abstract

The organic matter of rock phosphate has been the subject of numerous studies. The valuation and resolu-tion of some problems, such as fouling, encountered in the industrial production of phosphoric acid are of great interest, and enable better production yields of phosphoric acid. The solid deposits formed in the production of wet process phosphoric acid were characterized and revealed the malladrite, gypsum, trace metals, and the presence of organic matter. The identification of the organic matter was carried out in the fouling samples using FT-IR and Raman spectroscopies. The quantitative determination of the total organic matter content of the fouling samples was performed using the Walkley-Black and calcination methods. The knowledge of the organic matter in the fouling layers allows a better understanding of phenomena in processes.

Effect of Potassium Sulfate on the Portland Cement Pastes Setting Behavior

“…The observed solid phases in the fouling layers are principally composed by the malladrite (Na 2 SiF 6 ) form and gypsum (CaSO 4 .2H 2 O) minerals. 17,18 The FT-IR spectra confirm the presence of mallardite and gypsum phases and reveal a supplementary band that has been assigned to C-O vibrations in acids, esters, or ethers. This appearance indicates the possibility of the organic matter in the fouling layer.…”

“…The deposit was formed during a production cycle of 16 months and appears as a multilayer fouling which covers the entire inner surface of the reactor with considerable thicknesses. 18 The solid phases are formed predominantly of malladrite and gypsum and their chemical composition and some of their physical characteristics evolve over time and are impacted by the nature and quality of the processed phosphate. 19 The preparation of the fouling sample includes all the steps performed in the laboratory to make a sample in a form suitable for chemical analysis.…”

“…In our previous work, the fouling samples were homogenized and prepared on the micro-scale using a particle size fractionation. 18 The mineral deposits during attack-filtration and concentration operations were characterized using complementary techniques XRF, XRD, and IR. The elemental analyses have been performed for the fouling layers.…”

Thermodynamic Properties and Equilibrium Solubility of KH5P2O8(aq) at Different Temperatures, Experimental Study, and Thermodynamic Modeling

“…The result of water activity is presented as a function of molality m in the temperature range from 298. 15…”

“…Inorganic phosphate salts are considered a diverse class of materials with many important industrial uses, such as an ion exchange material, solid electrolytes for batteries, and electrolyte membranes, and they have been devoted to the study of transport properties in a wide class of proton conductors. − Alkali orthophosphates have been widely applied in agricultural production as potassium fertilizers. , Pyrophosphates in aqueous solutions are potential inhibitors of osteoclast activity and are employed to avert bone loss associated with ailments. , Due to the diversity of their applications, their main characteristic resides at the level of the network of hydrogen bonds and their association in solutions. , Previous studies at different temperatures investigated the thermodynamic characteristics of orthophosphate salt aqueous solutions. , The main goal was to comprehend the physicochemical structure and behavior of phosphate solutions, specifically the potential for phosphate complex and ion-pairing formation at high concentrations. However, understanding the behaviors and thermodynamic properties of bisphosphate salt solutions is crucial for a better comprehension of the physicochemical properties governing their practical applications in industry and the environment. − Therefore, the phosphate salts of type MH 5 P 2 O 8 (M = K, Na, Rb, and Cs) in aqueous solutions are of interest to determine thermodynamic properties and different chemical equilibria. , Indeed, in our recent work, the solid phase of potassium pentahydrogendiphosphate was synthesized and characterized in a reproducible manner using various analysis techniques . The qualitative and quantitative analyses of pentahydrogendiphosphate ions in dilute up to concentrated aqueous solutions were examined using Raman spectroscopy.…”