Process for recovering carboxylic acids from sugar cane industry by-products

Food industry by-products such as molasses and vinasses may provide an important source of organic acids. The aim of this study is to compare three processes, precipitation, chromatography and liquid-liquid extraction, for the recovery of carboxylic acids from sugarcane molasses from Réunion Island. Precipitation was performed with different temperatures by addition of calcium chloride. The results revealed that precipitation can recover aconitic acid efficiently from molasses. Liquid-liquid extraction was carried out with TBP in n-dodecane. The results indicated that the selectivity depends on solution pH. Extraction with molasses is hindered by the appearance of a third phase. Chromatography was performed on ion exchange resin (Amberlite IRA 900 Cl) from Rohm & Haas. The extraction yields were low in the synthetic solutions and the recovery of carboxylic acids from molasses was impossible due to their high viscosity

Urban Wastewater Treatment by Catalytic Ozonation

This study focuses on the catalytic ozonation of organic matter recalcitrant to usual water treatment technologies. Experiments aimed to investigate the efficiency of the process TOCCATA®, which uses a granular catalyst coupled with ozonation. Comparison was made between single ozonation, single adsorption onto the catalyst and catalytic ozonation. Adsorption was proven to contribute to decreased dissolved organic carbon. Catalytic ozonation enhanced organic matter removal and ozone transfer compared to single ozonation. Catalytic ozonation was modeled with global apparent first-order kinetics and single adsorption with pseudo–second-order sorption kinetics

Vapor-liquid equilibria measurements of bitter orange aroma compounds highly diluted in boiling hydro-alcoholic solutions at 101.3 kPa

In this work, experimental vapor−liquid equilibria (VLE) of water + ethanol + five aroma compound (two monoterpene hydrocarbons, α-pinene and D-limonene, and three oxygenated compounds, linalool, citral, and linalool oxide) mixtures were measured at boiling point at 101.3 kPa for ethanol molar fractions ranging from 0.0140 to 0.8389. The five aroma compounds were selected for their strong contribution to the aroma of the distillate of bitter orange essential oil. First, the thermodynamic consistency of the experimental VLE data was validated. Then the NRTL and Henry's law type models were tested to correlate the experimental data. Good agreement was obtained with both models to predict the phase equilibrium of the oxygenated compounds, and a better agreement was obtained with Henry's law type models for the monoterpene hydrocarbons in this kind of mixture

Two industrial examples of coupling experiments and simulations for increasing quality and yield of distilled beverages

The aim of this study was to check the ability of ProSim® software to model both continuous and batch distillations of two specific industrial units in order to obtain both a better understanding of the behaviour of aroma volatile components and a tool to optimise the still's operation. Simulations of multistage continuous distillation to produce neutral spirit from raw alcohol and of batch distillation to produce bitter orange distillate from bitter orange peels macerate were carried out with ProSimPlus and BatchColumn software. Simulations were compared with distillations performed in two industrial plants. For each case, the industrial plants were studied to determine all the operating parameters and the behaviour of certain compounds selected for their high concentration or quality impact. Then, the NRTL and Henry's law thermodynamic models were chosen. Simulation results of particular compositions of the selected compounds in the different extractions were analysed and compared with experimental measurements. Simulations represented faithfully the behaviour of compounds in the industrial plants. Therefore, it was possible for two totally separated cases to illustrate the interest of simulation software; for neutral spirit production to determine new operation set points in order to maximise productivity and improve quality for neutral spirit production and for bitter orange distillate production, to explain the choice of different cuts and the role of the presence of peels during distillation

Extraction par solvant (étude et modélisation du système tributylphosphate-acides monocarboxyliques)

This work concerns the study of the liquid-liquid extraction as a method of recovery and valorization of the carboxylic acids in agro-industrial's effluents. The feasibility of such a process can be established only by investigating all the equilibria involved during the process of extraction. Initially, a detailed study of the mechanism known as reaction at the interface made it possible to touch the limits of application of this model when the operational parameters change, thus, this criticism led to a revision of the assumptions on which this model is founded. Taking into account the solubility of Tributylphosphate in aqueous phase, a model known as of reaction in the aqueous phase was proposed. It was applied successfully to five monoacids with a broad area of initial concentration of acid, three solvent ratios and eight concentration of extractant (TBP) diluted in dodecane. Finally, the model was extrapolated and validated on liquid-liquid equilibrium data with two carboxylic acids extracted at the same timeTOULOUSE-ENSIACET (315552325) / SudocSudocFranceF

Study of the degradation of pesticides on loaded seeds by ozonation

International audienceEvery year in France, seed producers must downgrade more than 12,000 tons of seeds. These seeds are currently incinerated in cement factories at seed producers’ expenses and non-available for the processes of valorization of renewable resources, due to their significant pesticide content. Consequently, the quantity of pesticides present in the seed loading must be reduced before a subsequent valorization of the downgraded seeds. The purpose of this work is thus to develop a process for the decomposition of a large amount of the pesticides present in the seed loading. Ozonation was proved to be efficient in wastewater treatment for the removal of pesticides of interest, usually present in the seed loading. Consequently, ozone was applied to soft wheat seeds loaded with Gaucho Ble´ loading solution, in a fixed bed reactor. The humidification of seeds before ozonation, the concentration of ozone in the inlet gas and the ozonation time were revealed to be the predominant factors to accelerate the kinetics of degradation of pesticides in the seed loadings. Using optimal conditions (determined by a Box–Behnken experimental design), pesticides were successfully decomposed (respectively 99 and 90% for the degradation of imidacloprid and bitertanol), within 96 min of treatment. The kinetic laws for the ozonation reactions of both pesticides were also determined and the partial orders of the reaction were 1 for both ozone and the pesticide. The subsequent application of this process for the treatment of other loaded seeds showed good degradation yields for all the studied pesticides and demonstrated the interest of such a process for the removal of pesticides on loaded seeds

Étude de la décomposition de produits phytosanitaires par l'ozone (Application au traitement des semences déclassées)

Thèse confidentielleThèse confidentielleTOULOUSE-INP (315552154) / SudocSudocFranceF

Extraction d'un acide organique à partir de co-produits issus de l'industrie de la canne à sucre

Thèse confidentielleThèse confidentielleTOULOUSE-INP (315552154) / SudocSudocFranceF

Detailed investigation of lactic acid extraction with tributylphosphate dissolved in dodecane

International audienceThe aim of the present study was to Study the extraction of lactic acid with tributylphosphate (TBP) dissolved in a diluent (dodecane) over a broad range of acid concentrations and solvent compositions, to determine the apparent equilibrium constants and the number of reacting extractant molecules, and to elucidate the influence of different factors (preliminary washing of organic phase, change of phase volumes, pH at equilibrium, acid concentration) oil the extraction of the acid. It was found that the change of phase volumes after extraction should be taken into account For the calculation of different process parameters. The preliminary washing of the extractant does not significantly affect the overall distribution coefficients