Modeling and Optimization of Propane Selective Oxidation to Acrylic Acid Over Mo 1 V 0.3 Te 0.23 NB 0.12 O X Catalyst Using Artificial Neural Network and Box-Behnken Design

The prediction capability of response surface methodology (RSM) and artificial neural network (ANN) models for propane selective oxidation to acrylic acid (AA) over Mo1V0.3Te0.23Nb0.12Ox catalyst was investigated in this work. 15 experimental runs based on the Box-Behnken design (BBD) were employed to study the effects of temperature (380 to 500 °C), superficial velocity (33.3 to 66.7 mL (min gcat)-1), (O2)/(C3H8) ratio (1 to 3) and their interactions on propane conversion, AA selectivity and COx selectivity. The quadratic polynomial BBD equations and the feed-forward back propagation ANN models were developed based on the designed experimental data. Statistical analysis; coefficient of determination (R2), mean absolute error (MAE) and analysis of variance (ANOVA) illustrated that there was acceptable adjustment between BBD and ANN predicted responses as compared to experimental data. While, the ANN model showed a clear preference and generalization capability over BBD model in the case of experimental data set which were not used to training the models. In addition the optimum conditions were found to be temperature (461.7 °C), GHSV (51.9 mL (min gcat)-1) and (O2)/(C3H8) ratio (2.1) which were determined by desirability function approach. In these conditions, propane conversion of 15.2%, AA selectivity of 32% and COx selectivity of 44% which obtained experimentally were in reasonable agreement with predicted responses. Chemical Engineering Research Bulletin 21(2019) 1-19

Optimization of Energy Consumption in Acetic Acid and N-Butanol Esterification Reaction with Simultaneous Water Removal Using Novel Microcontroller Based Automated Reactor

This paper focuses on the optimization of energy consumption in esterification of acetic acid wherein the water removal is achieved by using silica gel desiccant in a microcontroller based automated reactor. Esterification reactions are endothermic hence, one can get more product, by increasing the temperature, thus disturbing the equilibrium. Heat of reaction (Hr) was estimated by using the heat capacity data and constants (C). Energy analysis and modelling was developed for the enhancement of process which is the key component of the systems. The mathematical model is validated by experimental results. In this paper, effect of parameters like desiccant weight, regeneration temperature and molar ratio on energy consumption are studied. Trends of energy effectiveness of several parameters are presented in the various regeneration temperatures and molar ratio and desiccant weight which confirmed the linear relationship with hot air flowrate. Decrease of 33% in power consumption was observed by decreasing the hot air flowrate by 10%.This is the conformity of validation of affinity law. The newly invented model was optimized for variables, hot air temperature, molar ratio and silica gel weight. The minimum energy consumption at 1 desirability was reported by software in the given range of parameters. When the hot air temperature, molar ratio and silica gel weight were 67.670C, 3 and 34.32 gm, then the minimum value of energy consumption was 29.59 Watt. Chemical Engineering Research Bulletin 21(2019) 46-57

Statistical Optimization of Lactic Acid Extraction Using Green Solvent and Mixed Extractants (TOA and TOMAC)

Since some previous years, reactive extraction has become more attractive and competitive technique for the separation and purification of lower carboxylic acids from fermentation broth as well as from dilute aqueous streams. This paper shows the results of investigation of reactive extraction of lactic acid (LA) from an aqueous solution using the synergistic mixture of the extractants (TOA (tri-n-octylamine) and TOMAC (Tri-n-octylmethylammonium chloride)) and a non-toxic and biocompatible green solvent (soybean oil). Three-level Box-Behnken design (BBD) under response surface methodology (RSM) was opted for the experimental design and to interpret the mutual effect of seven independent process parameters on the LA distribution coefficient (KD). The maximum values of LA distribution coefficient (KD=2.51) and its extraction efficiency (ηη=71.5%) were obtained for the optimum values of various process parameters such as 0.02 [M] initial LA concentration (CC1), 0.5 (v/v) extractant ratio (α), 28.66% (v/v) mixed extractants concentration (ψ), 2 (v/v) phase ratio (φ), 270C temperature (T), 102 rpm stirring speed (ω), and 63 mincontact time (τ). This present investigation will provide a noble discussion on LA reactive extraction using green solvent and on various influencing process parameters for gaining the enhanced value of LA distribution coefficient (KD). Chemical Engineering Research Bulletin 21(2019) 20-35

Numerical Solution of MHD Nanofluid Over a Stretching Surface with Chemical Reaction and Viscous Dissipation

The main objective of this paper is to focus on a numerical study of chemical reaction and viscous dissipation effects on the steady state boundary layer flow of MHD nanofluid past the horizontally stretching sheet with the existence of nanoparticles. A proper similarity transformation is utilized to convert the boundary layer equations into the nonlinear and coupled ordinary differential equations. These ODEs are sorted out numerically by applying the shooting mechanism. Graphical representations are also included to explain the effect of evolving parameters against the above-mentioned distributions. Significance of different physical parameters on dimensionless velocity, temperature and concentration are elaborated through graphs and tables. For increasing values of Eckert number, the temperature profile increases whereas the chemical reaction parameter increases, the boundary layer thickness decreases. Chemical Engineering Research Bulletin 21(2019) 36-45

Production and Performance Evaluation of Noble Fire Extinguishing Foam Suspensions Using Locally Available and Environmentally Friendly Natural Mineral Raw Materials

The main goal of this research is the fabrication of halogen free, environmentally friendly fire-extinguishing powders using local mineral raw materials and the development of technological processes for producing highly efficient fire-extinguishing foam-suspensions on the basis of the produced powders. Fire-extinguishing powders are made by mechanical treatment and mixing of raw materials: zeolite, clay shale, perlite and ammophos. The process does not need introduction of expensive, halogen-containing, hydrophobizators and ensures the cost-effective production of fire-extinguishing powders. The obtained fire-extinguishing powders are characterized by high performance properties, high fire-extinguishing capacity and coefficient of atomic oxygen recombination. Thus, they are characterized both by homogeneous and heterogeneous inhibition of combustion processes. The efficiency of the produced powders is not inferior to that of standard powders of common production. In addition, in contrast to their traditional analogs they are halogen free, environmentally friendly and cheaper (1.2-2 times cheaper). The obtained powders, unlike the ones of conventional production, have good compatibility with water and foam. Our foam-suspensions are prepared just by mechanical mixing of fire-extinguishing powders with water and surface-active substances – foamers. The process does not require chemical treatment of materials. Thus, the developed technology is simple and cost-effective. The foam-suspensions produced on the basis of the obtained powders have higher heat capacity, permeability, wetting effect like water and foam and unlike them, they allow for homogeneous as well as heterogeneous inhibition of the burning process. Thus, the so produced foam-suspensions will have higher extinguishing effect than water, foams or powders, taken separately. Based on the above, it can be suggested that the produced powders can be used for extinguishing all types of fires, including large-scale ones in a combination with water and foams. Chemical Engineering Research Bulletin 21(2019) 58-64

Influence of amino acid additives on solution behaviour of L-alanine

<p>The solubility experiment of L-alanine solution was performed in a 250ml jacketed glass crystallizer without and with amino acid additives at temperature from 15^oC to 75^oC by means of gravimetric method. On the whole, L-leucine additive significantly altered the solubility of L-alanine and Glycine additive caused an erratic pattern on the solubility data of L-alanine. The hydrophobic methyl side chain of L-leucine additives is believed to contribute to the formation of water clathrate in the solution which affected the interaction of L-alanine molecules in water solvent and thus modified the solubility of L-alanine. Finally, thermodynamic data analysis of L-alanine solution was extensively assessed. The negative deviation of L-alanine from the ideal solution is as a result of high solute-solvent interaction, which is due to the hydrophobicity and clathrate phenomenon of the water molecules in the solution.</p><p>Chemical Engineering Research Bulletin 20(2018) 23-29</p>

Derivation of Nanocellulose from Native Rice Husk

<p>Nanocellulose has been in numerous applications and can be obtained from bioresources. This work demonstrates the derivation of nanocellulose from an alternative option i.e. rice husk. The processed rice husk was refined by chemical and mechanical treatments. Nanocellulose was subsequently derived from the refined rice husk through acid hydrolysis followed by centrifugation, dialysis and ultrasonic treatment. Scanning Electron Microscopy ensured the nanoscale diameter while Fourier Transformed InfraRed Spectroscopy confirmed the removal of noncellulosic materials. It is therefore proposed that the native rice husk can also be utilized for manufacturing nanocellulose reducing its adverse environmental impacts.</p><p>Chemical Engineering Research Bulletin 20(2018) 19-22</p>

Modelling and Simulation of a Fluidized Bed Reactor for Minimum Ammonium Nitrate and Reduction of NOx Emissions

<p>Due to the environmental legislations related to the nitrates and their emissions, thermal decomposition of ammonium nitrate (AN) in a fluidized reactor (FR) is regarded one of the most reasonable chemical-free disposal process for an aqueous waste nitrate stream. Therefore, the present study is aimed to improve a mathematical model based on experiments (from the literature) for enhancing the design of such reactor in an environmentally friendly manner. Where, the optimal kinetic parameters of the relevant reactions are firstly obtained employing the optimization technique keeping in mind the goal to construct the model with high exactness. Such design factors are then utilized for the purpose of getting the optimal operating conditions of fluidized bed reactor (FBR) achieving the main target of this process with ammonium nitrate-free content (Nil) at the end of the reactor in addition to reducing the NO<em>_x</em><em> </em>emissions. The model is based on the two-phase theory of a FBR with predicting the concentration behavior along the reaction zone length for all components in the emulsion and bubble phases in addition to the temperature profile of the gas phase. New results related to output conversion of ammonium nitrate as well as NO content at the optimal operating conditions has been obtained in comparison with those reported in the literature.</p><p>Chemical Engineering Research Bulletin 20(2018) 8-18</p>

Determination of Optimum Drying Temperature Profile by Iterative Learning Control (ILC) Method to Obtain a Desired Moisture Content in Tablets

<p>The paper presents an industrial case study example to evaluate the performance of the linear time varying (LTV) perturbation model based iterative learning control (ILC) in a pilot scale batch system. The operating data based strategy applied here is based on utilizing the repetitive nature of batch processes to update the operating trajectories using process knowledge obtained from previous runs and thereby providing a convergent batch-to-batch improvement of the process performance indicator. The method was applied to determine the required drying temperature of Paracetamol granules to obtain desired moisture content at the end of the batch. After granulation operations, Paracetamol granules were dried in a fluid bed dryer in the pilot plant laboratory of GlaxoSmithKline Bangladesh Limited, Chittagong, Bangladesh. These results demonstrate the potential of the ILC approach for controlling batch processes without rigorous process models.</p><p>Chemical Engineering Research Bulletin 20(2018) 1-7</p>

Thermodynamic properties of the dodecylbenzenesulfonic acid-acetone binary liquid mixture using a modified flory theory

<p>Prigogine–Flory–Patterson (P-F-P) theory was applied for the correlation the experimental data of excess molar volume for the binary liquid mixture of DBSA-Acetone at the temperature range of (293.15-303.15 K). The three contribution terms (pressure, interaction and free volume) in the P-F-P equation were compared with the total effect of P-F-P equation. A positive excess molar volume were obtained at all the range of mole fraction and at all the temperatures. The maximum value of excess molar volume was positioned at the 0.4 mole fraction. Eyring-Flory-Huggins theory was found useful in the estimation of the viscosity deviation variation with mole fraction at the same temperature range. A negative deviation was found in the viscosity for all the range of temperature and mole fraction. The maximum deviation in the viscosity was found at the mole fraction of 0.4. The increase in the negative deviation values with temperature was interpreted as a result of the decrease in the attractive forces between the like molecules.</p><p>Chemical Engineering Research Bulletin 20(2018) 30-35</p>