Chemical Engineering
Mohammadreza Khosravi-Nikou; Ahmad Shariati; Mohammad Mohammadian; Ali Barati; Adel Najafi-Marghmaleki
Abstract
This study presents a robust and rigorous method based on intelligent models, namely radial basis function networks optimized by particle swarm optimization (PSO-RBF), multilayer perceptron neural networks (MLP-NNs), and adaptive neuro-fuzzy inference system optimized by particle swarm optimization methods ...
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This study presents a robust and rigorous method based on intelligent models, namely radial basis function networks optimized by particle swarm optimization (PSO-RBF), multilayer perceptron neural networks (MLP-NNs), and adaptive neuro-fuzzy inference system optimized by particle swarm optimization methods (PSO-ANFIS), for predicting the equilibrium and kinetics of the adsorption of sulfur and nitrogen containing compounds from a liquid hydrocarbon model fuel on mesoporous materials. All the models were evaluated by the statistical and graphical methods. The predictions of the models were also compared with different kinetics and equilibrium models. The results showed that although all the models lead to accurate results, the PSO-ANFIS model represented the most reliable and dependable predictions with the correlation coefficient (R2) of 0.99992 and average absolute relative deviation (AARD) of 0.039%. The developed models are also able to predict the experimental data with better precision and reliability compared to literature models.
Chemical Engineering
Seyede Leila Ebrahimi; Mohammadreza Khosravi-Nikou; Seyed Hassan Hashemabadi
Abstract
In this research, the effects of important parameters, including the molar ratio of acetic acid to sulfur(S) , sonication time, temperature, and hydrogen the molar ratio of peroxide to sulfur on the performance of ultrasound-assisted oxidative desulfurization were studied using the response surface method ...
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In this research, the effects of important parameters, including the molar ratio of acetic acid to sulfur(S) , sonication time, temperature, and hydrogen the molar ratio of peroxide to sulfur on the performance of ultrasound-assisted oxidative desulfurization were studied using the response surface method (RSM). To this end, a model fuel containing n-decane and dibenzothiophene at a concentration of 1000 ppm was used. It was found out that the temperature and acetic acid/S molar ratio were the most influencing parameters affecting the conversion of sulfur compound. The synergistic effects of the parameters were also investigated, and it was discovered that the maximum conversion of dibenzothiophene reached 98.59% when H2O2/S, acetic acid/S, temperature, and sonication time were set to 167, 330, 80 °C, and 30 min respectively. Finally, the apparent kinetics of dibenzothiophene oxidation and the activation energy of reaction were presented.
mirroozbeh jamei; mohammad khosravi nikou
Abstract
This research reported a new method of removal of Pb+2from water by using a nano zero valent iron (nZVI) assisted ultrasonic wave. At first, nZVI was synthesized by an ultrasound assisted method. Particles morphology and surface composition were characterized by FESEM, XRD, and EDX. The XRD patterns ...
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This research reported a new method of removal of Pb+2from water by using a nano zero valent iron (nZVI) assisted ultrasonic wave. At first, nZVI was synthesized by an ultrasound assisted method. Particles morphology and surface composition were characterized by FESEM, XRD, and EDX. The XRD patterns showed that the crystallinity of the nZVI prepared using ultrasonic conditions was higher than the conventional method. According to the EDX pattern, 67% of particle composition was nZVI. The synthesized nanoparticles were then utilized as a Fenton-like catalyst for the removal of Pb+2from water using an ultrasound assisted method. In the present study, ultrasound power, temperature effects, nZVI, and reaction time were optimized. From the studies, it has been observed that removal does not increase indefinitely with an increase in ultrasound power, but it instead reaches an optimum value and decreases with a further increase in the ultrasound power. The removal of Pb+2increased with increasing temperature, nZVI, and H2O2 concentration. The result indicated that the efficiency of hydrocarbon removal by this novel method was 97.87%.
Hadi Zareei; Mohammadreza Khosravi Nikou; Ahmad Shariati
Abstract
A consequence analysis was performed in one of the gas refineries in Iran to investigate the risks andpotential losses resulted from accidents. Specifically, the consequences of an explosion in LPGspherical tanks were modeled using PHAST and MATLAB software. In this paper, three methods ofcalculation ...
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A consequence analysis was performed in one of the gas refineries in Iran to investigate the risks andpotential losses resulted from accidents. Specifically, the consequences of an explosion in LPGspherical tanks were modeled using PHAST and MATLAB software. In this paper, three methods ofcalculation of PHAST software TNT, multi-energy, and BST were used. The results showed thatmulti energy method is the best method to evaluate overpressure. It was 0.150 bar and 0.159 bar in adistance of 1000 m far from the blast using PHAST and MATLAB respectively. This overpressurecan damage a wall with 30 cm thickness. It also affects the human threshold (1%) ruptured eardrum.Finally, it was found that 100% lethality in a minute happened at 285.5 m and 37.5 kW/m2 when theexplosion happened.
Sina Rashidi; Mohammad Reza Khosravi Nikou; Bagher Anvaripour; Touba Hamoule
Abstract
The performance of MSU-S and its forms modified with phosphotungstic acid (HPW) and nickel (Ni) for the desulfurization and denitrogenation of model diesel fuel were studied. According to the results of the characteristic tests (N2 adsorption-desorption, XRD, SEM, and NH3-TPD), heteropoly acid incorporation ...
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The performance of MSU-S and its forms modified with phosphotungstic acid (HPW) and nickel (Ni) for the desulfurization and denitrogenation of model diesel fuel were studied. According to the results of the characteristic tests (N2 adsorption-desorption, XRD, SEM, and NH3-TPD), heteropoly acid incorporation causes higher acidity along with a negligible loss of structural aspects, while Ni impregnation leaves a drastic negative effect on mesoporous structure, crystalline phase, and particle shape along with a positive impact on surface acidity. With both modifications (HPW and Ni), the maximum increase of 33.18% and 6.88% was occurred for the adsorption loading of total sulfur and total nitrogen respectively. The adsorption loading and selectivity of all the adsorbents for total nitrogen were slightly more than those for total sulfur (the selective adsorption of nitrogen over sulfur). The pseudo-second order model can best fit the kinetics data and Freundlich model can best describe the equilibrium isotherm for all the species over Ni/HPW-MSU-S.
Mir Roozbeh Jamei; Mohammadreza Khosravi Nikou; Bagher Anvaripour
Abstract
A new method for the synthesis of nano zero-valent iron (nZVI) was developed in the present study. Ultrasonic waves, as a novel method, were used to synthesize the nanoparticles. The morphology and surface compositions of the particles were characterized by using FESEM, XRD, BET, and particle size analyzer. ...
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A new method for the synthesis of nano zero-valent iron (nZVI) was developed in the present study. Ultrasonic waves, as a novel method, were used to synthesize the nanoparticles. The morphology and surface compositions of the particles were characterized by using FESEM, XRD, BET, and particle size analyzer. The synthesized nanoparticles were then utilized as a Fenton-like catalyst to degrade of hydrocarbon contaminants of soil. The effect of using ultrasonic waves in combination with nZVI for hydrocarbon degradation was also investigated. The effects of ultrasonic power, nZVI concentration, pH, hydrogen peroxide concentration, and temperature on remediation were studied. It was found that the new nZVI synthesized by an ultrasound-assisted method had high efficiency in soil remediation. The results indicated that the efficiency of removing hydrocarbons by nZVI was 98.57%. Finally, the optimum conditions of degradation were obtained when pH, ultrasonic power, nZVI concentration temperature, and hydrogen peroxide concentration were respectively equal to 3.5, 500 W, 0.4 gr.l-1, 40 °C, and 30 mM.
