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Engis, Belgium

Belboom S.,University of Liege | Szocs C.,Prayon SA | Leonard A.,University of Liege
Journal of Cleaner Production | Year: 2015

This paper undertakes an environmental evaluation of phosphoric acid production, using industrial data from Prayon SA in Belgium. Phosphoric acid is produced using the wet di-hemihydrate process also called Central Prayon process. Both grades of phosphoric acid are evaluated: fertilizer and purified grades. Specificities of this plant are highlighted and improvements of the process in terms of energy and facilities integration through years are quantified as environmental benefits. The implementation on site of two sulphuric acid production facilities and their energetic integration allow a reduction of climate change impact of 80%. Results also show the importance of phosphogypsum valorisation which is sold for the main part in this case study. Concerning the purified grade, this specific process has been compared to the thermal process, using Best Available Techniques (BAT) values for the modelling. It shows a reduced environmental impact for the wet process in the majority of categories studies. © 2015 Elsevier Ltd. Source

Mahy J.G.,University of Liege | Leonard G.L.-M.,University of Liege | Pirard S.,University of Liege | Wicky D.,AC&CS CRM GROUP | And 5 more authors.
Journal of Sol-Gel Science and Technology | Year: 2016

Abstract: A process has been developed to enable the large-scale production of pure TiO2 films deposited on 316L stainless steel in order to get an easy-to-clean surface. This large-scale process requires an easy aqueous sol–gel procedure for the synthesis of the TiO2 sol. This synthesis has been simplified to facilitate the extrapolation toward an industrial scale. Results of TEM, photocatalytic properties, film hydrophilicity and texture obtained with the simplified aqueous sol–gel synthesis (IsoP–TiO2 synthesis) show similar properties to those obtained with the standard aqueous sol–gel synthesis of TiO2 (HAc–TiO2 synthesis) developed previously. Only, X-ray diffraction patterns showed differences, with the presence of anatase-brookite phases in IsoP–TiO2 synthesis while anatase phase only was observed in HAc–TiO2 synthesis. Both the aqueous sol–gel synthesis of pure TiO2 and the film deposition on steel by roll-coating have been successfully extrapolated to a larger scale. The photocatalytic activity and the hydrophilicity of the film were found to be unchanged when compared to films produced at a laboratory scale, thus validating the production of an efficient easy-to-clean material. Although some problems are still to be solved, this study is a hopeful first step in the development of a large-scale process for self-cleaning steel production. Graphical Abstract: [Figure not available: see fulltext.] © 2016 Springer Science+Business Media New York Source

Kohn G.,University of Liege | Delvaux D.,University of Liege | Lakaye B.,University of Liege | Servais A.-C.,University of Liege | And 7 more authors.
PLoS ONE | Year: 2012

Background: We recently characterized a specific inorganic triphosphatase (PPPase) from Nitrosomonas europaea. This enzyme belongs to the CYTH superfamily of proteins. Many bacterial members of this family are annotated as predicted adenylate cyclases, because one of the founding members is CyaB adenylate cyclase from A. hydrophila. The aim of the present study is to determine whether other members of the CYTH protein family also have a PPPase activity, if there are PPPase activities in animal tissues and what enzymes are responsible for these activities. Methodology/Principal Findings: Recombinant enzymes were expressed and purified as GST- or His-tagged fusion proteins and the enzyme activities were determined by measuring the release of inorganic phosphate. We show that the hitherto uncharacterized E. coli CYTH protein ygiF is a specific PPPase, but it contributes only marginally to the total PPPase activity in this organism, where the main enzyme responsible for hydrolysis of inorganic triphosphate (PPPi) is inorganic pyrophosphatase. We further show that CyaB hydrolyzes PPPi but this activity is low compared to its adenylate cyclase activity. Finally we demonstrate a high PPPase activity in mammalian and quail tissue, particularly in the brain. We show that this activity is mainly due to Prune, an exopolyphosphatase overexpressed in metastatic tumors where it promotes cell motility. Conclusions and General Significance: We show for the first time that PPPase activities are widespread in bacteria and animals. We identified the enzymes responsible for these activities but we were unable to detect significant amounts of PPPi in E. coli or brain extracts using ion chromatography and capillary electrophoresis. The role of these enzymes may be to hydrolyze PPPi, which could be cytotoxic because of its high affinity for Ca2+, thereby interfering with Ca2+ signaling. © 2012 Kohn et al. Source

Ach D.,CNRS Automation and Process Engineering Laboratory | Briancon S.,CNRS Automation and Process Engineering Laboratory | Dugas V.,University Claude Bernard Lyon 1 | Pelletier J.,CNRS Automation and Process Engineering Laboratory | And 2 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2015

Complex coacervation between whey proteins isolate (WPI) and Acacia gum was investigated in order to disclose the roles and the contributions of each component of WPI to the formation of the complex coacervate. The main aim was to establish the balance of the main components of WPI, β-lactoglobulin and α-lactalbumin, during the phase separation of complex coacervate. The complex coacervation of Acacia gum and pure β-lactoglobulin, pure α-lactalbumin, and WPI have been investigated and compared together by means of macroscopic observations and capillary gel electrophoresis analyses performed along pH scans from basic to acidic medium. Coacervate composition was influenced by the protein/polysaccharide (Pr:Ps) ratio and pH. An optimum pH for best coacervation yield was found for each Pr:Ps ratio. Non-negligible concentrations of β-lactoglobulin and α-lactalbumin remain in solution in most instances. β-lactoglobulin undergoes complex coacervation stronger than α-lactalbumin in their competitive coacervation of WPI and Acacia gum. © 2015 Elsevier B.V. Source

Prayon Sa | Date: 2013-05-16

A process for manufacturing a composite material comprising a functionalization of the substrate, which comprises treatment of said substrate with at least one first alcoholic solvent, functionalization of a first powder and formation of a first colloidal sol of said functionalized first powder in a second solvent, at least one application of a layer of said first colloidal sol of said first powder to the substrate, drying of said layer of said first colloidal sol and formation of a layer of first coating formed by said first colloidal sol, adherent to said substrate, by heating at a temperature above 50 C. and below 500 C.

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