A design of jet mixed tank

Jet mixing has become alternative to conventional impeller mixing for various applications in process industries. Mixing time is an important design parameter in jet mixing. Many authors have used different parameters like jet velocity, jet diameter, tank height etc to find out the correlation for mixing time. There is no comprehensive review, which tells exclusively about these parameters used for jet mixing. Recently many authors have used CFD in order to overcome experimental limitations for design of jet mixed tanks. A critical analysis of the available literature data has been made and some general conclusions have been drawn concerning the various parameters. This review focuses on the study of various parameters used in experimental and CFD work on jet mixed tanks to get the optimum design procedure

Process intensification of esterification reaction for the production of propyl butyrate by pervaporation

Pervaporation is a membrane separation process vastly used for purification in chemical and allied industries. Esterification reaction can be intensified and enhanced by coupling with pervaporation reactor (PVR). Polyvinyl alcohol (PVA)/polyethersulfone (PES) composite membrane was used for the pervaporation coupled esterification reaction study. Esterification of butyric acid with n-propanol was taken as a model reaction for the study and to test the performance of pervaporation reactor. Catalyst p-toluenesulfonic acid was used for the esterification reaction. The effects of various reaction parameters on conversion of butyric acid such as reaction temperature, initial molar ratio of n-propanol to butyric acid, catalyst loading and reaction time were studied. Experimental results show that the increase of temperature, initial molar ratio, and catalyst concentration enhance the conversion of butyric acid considerably. The highest conversion of 96.41% was obtained at temperature 353 K, molar ratio of 2 and catalyst loading of 2.5%w/w at reaction time of 420 minutes. PVA/PES membrane used in the experiments shows the good activity and hydrophilicity and plays a vital role for enhancing the conversion by selectively removing water. Pervaporation coupled esterification shows the better choice over the conventional route for the production of esters. This technique is environment friendly and energy intensified approach as it reduces pollution and energy requirement

Optimization of adsorptive removal of α-toluic acid by CaO2 nanoparticles using response surface methodology

The present work addresses the optimization of process parameters for adsorptive removal of α-toluic acid by calcium peroxide (CaO2) nanoparticles using response surface methodology (RSM). CaO2 nanoparticles were synthesized by chemical precipitation method and confirmed by Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) analysis which shows the CaO2 nanoparticles size range of 5-15 nm. A series of batch adsorption experiments were performed using CaO2 nanoparticles to remove α-toluic acid from the aqueous solution. Further, an experimental based central composite design (CCD) was developed to study the interactive effect of CaO2 adsorbent dosage, initial concentration of α-toluic acid, and contact time on α-toluic acid removal efficiency (response) and optimization of the process. Analysis of variance (ANOVA) was performed to determine the significance of the individual and the interactive effects of variables on the response. The model predicted response showed a good agreement with the experimental response, and the coefficient of determination, (R2) was 0.92. Among the variables, the interactive effect of adsorbent dosage and the initial α-toluic acid concentration was found to have more influence on the response than the contact time. Numerical optimization of process by RSM showed the optimal adsorbent dosage, initial concentration of α-toluic acid, and contact time as 0.03 g, 7.06 g/L, and 34 min respectively. The predicted removal efficiency was 99.50%. The experiments performed under these conditions showed α-toluic acid removal efficiency up to 98.05%, which confirmed the adequacy of the model prediction

Modeling the adsorption of benzeneacetic acid on CaO2 nanoparticles using artificial neural network

The present work reported a method for removal of benzeneacetic acid from water solution using CaO2 nanoparticle as adsorbent and modeling the adsorption process using artificial neural network (ANN). CaO2 nanoparticles were synthesized by a chemical precipitation technique. The characterization and confirmation of nanoparticles have been done by using different techniques such as X-ray powder diffraction (XRD), high resolution field emission scanning electron microscope (HR-FESEM),transmittance electron microscopy (TEM) and high-resolution TEM (HRTEM) analysis. ANN model was developed by using elite-ANN software. The network was trained using experimental data at optimum temperature and time with different CaO2 nanoparticle dosage (0.002-0.05 g) and initial benzeneacetic acid concentration (0.03-0.099 mol/L). Root mean square error (RMS) of 3.432, average percentage error (APE) of 5.813 and coefficient of determination (R2 ) of 0.989 were found for prediction and modeling of benzeneacetic acid removal. The trained artificial neural network is employed to predict the output of the given set of input parameters. The single-stage batch adsorber design of the adsorption of benzeneacetic acid onto CaO2 nanoparticles has been studied with well fitted Langmuir isotherm equation which is homogeneous and has monolayer sorption capacity

Enhancement of esterification conversion using pervaporation membrane reactor

In the present study, the esterification reaction of propionic acid with isobutyl alcohol to produce isobutyl propionate and water was studied. The performance of esterification reaction was compared by using the batch process and the pervaporation assisted hybrid process which performs the reaction and separation simultaneously. A polyvinyl alcohol-polyethersulphone (PVA-PES) hydrophilic polymeric membrane was used in the study to separate water and also to shift the equilibrium. The influence of process parameters such as catalyst loading, molar ratio of acid to alcohol, reaction temperature and ratio of membrane area to initial reaction volume (S/V) was studied. The results showed that the pervaporation assisted esterification process gave more conversion than the batch process of esterification. The membrane showed high selectivity to the removal of water in the propionic acid, isobutyl alcohol, isobutyl propionate and water mixture. Moreover, the conversion of propionic acid was enhanced by enhancing the catalyst amount, molar ratio of acid to alcohol, reaction temperature and S/V ratio

Liquid-Liquid Extraction of Itaconic Acid from the Aqueous Phase Using Natural and Chemical Solvents

Itaconic acid, also known as methylene succinic acid, is a colorless, crystalline substance that is found in nature. Due to its two functional carboxylic acid forms and - unsaturated bond, it can be used in a variety of sectors (plastics, super-absorbents, biopolymers, anti-scaling agents, etc.). Itaconic acid can be produced via thermally decarboxylating citric acid, catalysing the condensation of succinic acid derivatives with formaldehyde, decarboxylating aconitic acid, and fermentation utilizing Aspergillus terreus and other microbes. It is quite expensive and harmful to extract itaconic acid from the fermentation broth. In the present study, Iso-butanol, iso-octanol, groundnut, soybean, mustard, and rice bran oil were incorporated as solvents for separating itaconic acid from their solutions in distilled water. Liquid-liquid extraction experiments were conducted over the range of 0.08-0.533 mol.L-1 of itaconic acid. The results thus obtained were defined as the separation efficiency (E) and distribution coefficient (KD). Separation was observed at maximum efficiencies of 69.33%, 47.8%, 12.93%, 17.9%, 15.625% & 14.18% with iso-butanol, iso-octanol groundnut, soybean, mustard, and rice bran oil respectively. Since the solvents used in this study were natural and chemical, it can be helpful to make the process more eco-friendly and the efficiency of the process can be further increased with the help of reactive extractants

Synthesis, Characterization and Application of 1-Butyl-3 Methylimidazolium Chloride as Green Material for Extractive Desulfurization of Liquid Fuel

The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, 1H-NMR, and 13C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency

Reactive extraction of propionic acid using Aliquat 336 in MIBK: Linear solvation energy relationship (LSER) modeling and kinetics study

708-713This study presents linear solvation energy relationship (LSER) modeling of reactive extraction of propionic acid using Aliquat 336 in MIBK as diluent. Reaction was slow in Aliquat 336 + MIBK with rate constant at 0.0079 (m3/kmol)0.55 s-1.Order of reaction with respect to acid and Aliquat 336 was 1 and 0.9 respectively. Modeling of reactive extraction equilibria using LSER was carried out and predicted a close resemblance of experimental data