Experimental Investigation of Reactive Extraction of Levulinic Acid from Aqueous Solutions

The separation of levulinic acid from aqueous solutions is costly and non-ecofriendly in many cases. The major concerns are the low concentration of levulinic acid in fermentation broths and industrial downstreams. In this study, reactive extraction of levulinic acid from aqueous phase is proposed and its efficacy was investigated. Various extractants viz. tri-n-butyl phosphate, trioctylamine, and trioctylmethylammonium chloride along with i-octanol as a diluent were used. The extent of separation was investigated and various performance parameters like extraction efficiency, distribution coefficient, equilibrium complexation constant, and loading ratio were estimated. The number of transfer units, diffusivity, and mass transfer considerations were also discussed in the reactive separation system. Finally, the conceptual method was provided for the separation of levulinic acid using efficient reactive separation. This work is licensed under a Creative Commons Attribution 4.0 International License

Reactive Extraction of Propionic Acid Using Aliquat-336 in 2-Octanol: Linear Solvation Energy Relationship (LSER) Modeling and Kinetics Study

Reactive extraction is an important recovery method for extraction of propionic acid from dilute streams, providing numerous advantages like high selectivity and recovery. Equilibrium and kinetic study of reactive extraction is essential to choose a proper extractant-diluent for acid recovery and ascertain the kinetic parameters essential for design of the process. In this paper, the linear solvation energy relationship (LSER) modeling of reactive extraction of propionic acid using Aliquat 336 in 2-octanol as diluent was presented to obtain the model parameters. Also, the kinetics of extraction in stirred cell was presented to explain the progress of reactive extraction of propionic acid using Aliquat 336 in the diluent. The reaction was found to be fast pseudo first order. To design the reactor to carry out reactive extraction, the kinetic parameters evaluated are essential. Modeling using LSER model predict a close resemblance of experimental data

Recovery of Acrylic Acid Using Calcium Peroxide Nanoparticles: Thermodynamics and Continuous Column Study

The thermodynamic parameters (DGº, DHº, and DSº) for adsorption of acrylic acid on CaO2 nanoparticle were estimated in the temperature range of 300.15 – 313.15 K, which helps to evaluate the feasibility of adsorption process, nature of adsorption process, and affinity of adsorbent toward solute molecule. A dynamic adsorption study in a fixed-bed column was performed using CaO2 nanoparticle for the recovery of acrylic acid from aqueous stream. The breakthrough curves of adsorption system were obtained for different process variables, such as initial acrylic acid concentration (2882–7206 mg L–1), flow rate (5–9 mL min–1), and bed height (10–20 cm). The bed-depth service time model, Thomas model, Yoon-Nelson model, and deactivation kinetic model were applied to the experimental data to predict the column performance. The data were in good agreement with the deactivation kinetic model. The presented results may be useful for the design of adsorption system using nanoparticles, which can be further extended to other systems. This work is licensed under a Creative Commons Attribution 4.0 International License

Reactive Crystallization of Calcium Oxalate: Population Balance Modeling

Reactive crystallization of calcium oxalate has been studied to determine particle size distribution for calcium oxalate precipitation using population balance model with method of moments. The model is formulated and tested for single feed semi-batch reactive crystallization of calcium oxalate with reactants calcium chloride and sodium oxalate with literature data. The simulated results include local supersaturation distribution, number of particle distribution, mass of particle crystallized, particle size, nucleation and growth rate during the process. The model results are in good agreement with available experimental data from literature. This work is licensed under a Creative Commons Attribution 4.0 International License

Recovery of Acrylic Acid Using Calcium Peroxide Nanoparticles: Synthesis, Characterisation, Batch Study, Equilibrium, and Kinetics

Recovery of acrylic acid from aqueous solution using low-cost CaO2 nanoparticles was investigated. CaO2 nanoparticles were synthesized by co-precipitation technique and characterised using XRD and FTIR. A mechanism was proposed for adsorption of acrylic acid onto CaO2 nanoparticles based on FTIR analysis. Acrylic acid recovery is highly dependent on contact time, CaO2 nanoparticle dosage, initial acrylic concentration, and temperature. Langmuir, Freundlich, Dubinin-Radushkevich, Tempkin, Hill, Redlich-Peterson, Sips and Toth isotherms were used and well represented by Redlich-Peterson isotherm (R2 = 0.9998) as compared to other isotherms. Kinetic studies revealed pseudo-second-order kinetics (k2 = 1.962·10–4 g mg–1 min–1) for adsorption of acrylic acid onto CaO2 nanoparticles. CaO2 nanoparticles exhibited high acrylic acid recovery over varied concentration ranges. The acrylic acid can be regenerated by desorption from the surface of adsorbent and utilised for numerous applications. The presented results may be useful for the design of adsorption system using nanoparticles, which can be extended to other systems. This work is licensed under a Creative Commons Attribution 4.0 International License

Reactive Extraction of Propionic Acid Using Tri-N-butyl Phosphate in Petroleum Ether: Equilibrium Study

In present paper, the recovery of propionic acid from aqueous phase by reactive extraction was studied using tri-n-butyl phosphate (TBP) in petroleum ether. Extraction using pure diluent was found to be poor. Using the mixture of extractant-diluent the extraction was significantly improved. Results were presented in terms of distribution coefficient, equilibrium complexation constant, loading ratio and extraction efficiency. Propionic acid and TBP were found to form (γ = 1:1) complex with no overloading

Stoichiometric and Spectroscopic Study of Reactive Extraction of Phenylacetic Acid with Tri-n-Butyl Phosphate

Phenylacetic acid is widely used in the pharmaceutical industry for production of antibiotics. The recovery of phenylacetic acid from dilute aqueous waste with tri-n-butyl phosphate in methyl isobutyl ketone and petroleum ether has been attempted, and the results are presented in terms of distribution coefficient, extraction efficiency, apparent equilibrium constant, and loading ratio. The mechanism of reactive extraction was analyzed and the stoichiometric ratio of phenylacetic acid to tri-n-butyl phosphate in methyl isobutyl ketone and petroleum ether was found to be 1:0.5 and 1:1.2. Mass action law was used to represent the reactive extraction equilibrium for phenylacetic acid−tri-n-butyl phosphate−diluents which satisfied much in the present study. FTIR spectroscopy was studied for confirmation of the formation of a complex between acid and extractant. Further relative basicity approach has been extended to represent the experimental results. The model is best suited to experimental results

Reactive Separation of Gallic Acid: Experimentation and Optimization Using Response Surface Methodology and Artificial Neural Network

Gallic acid is a major phenolic pollutant present in the wastewater generated from cork boiling, olive mill, and pharmaceutical industries. Experimental and statistical modelling using response surface methodology (RSM) and artificial neural network (ANN) were carried out for reactive separation of gallic acid from aqueous stream using tri-nbutyl phosphate (TBP) in hexanol. TBP has a more significant effect on extraction efficiency as compared to temperature and pH. The optimum conditions of 2.34 g L–1, 65.65 % v/v, 19 oC, and 1.8 of initial concentration of gallic acid, concentration of TBP, temperature, and pH, respectively, were obtained using RSM. Under optimum conditions, extraction efficiency of 99.45 % was obtained for gallic acid. The ANN and RSM results were compared with experimental unseen data. Error analysis suggested the better performance of ANN for extraction efficiency predictions