Iranian Journal of Chemistry and Chemical Engineering
Volume:42 Issue: 1, Jan 2023

In this study for wastewater remediation, we aimed to prepare Environmentally Sensitive Hydrogels (ESHs) with specific properties to remove copper (Cu2+) from wastewater. ESHs were prepared with inter-complex and amphoteric properties by the free radical polymerization method. We prepared two monomers, vinylpyrrolidone (VP) and Methacrylic Acid (MA). N,N'-methylenebisacrylamide was a cross-linker agent to prepare ESHs for binding Cu2+ to remove from wastewater. To characterize the structural behavior of synthesized ESHs, we used FT-IR. Thermal properties were investigated by using TGA. We used Scanning Electron Microscopy (SEM) micrographs for morphologic studies. Swelling and diffusion studies were performed at different pH, temperatures, and salt solutions. The amphoteric property and inter-complex formation between VP and MA were monitored by UV spectroscopy. In the Cu2+ bindings onto ESH experiments, a Langmuir-type (L) adsorption was observed regarding the Giles classification system. Binding parameters such as equilibrium constant (KL), monolayer coverage (Qm), and maximum fractional occupancy (FO%) were calculated as 0.16 L 1/gESH, 30 MgCu2+1/gESH, and 81%, respectively. We found a powerful electrostatic effect between the ionic part of ESH and cationic Cu2+. These interactions denote the removal of cationic heavy metals and organic toxic wastes for water treatment.

In recent years, a strong interest has emerged in hybrid composites and their potential uses, especially in Chitosan Nanoparticle – MontMorillonite - Titanium dioxide - (CSNP – MMT - TiO2) composites, which have interesting technological properties and applications. Using the Precipitation Method, Chitosan Nanoparticles with TiO2 Nanocomposite (CSNP – MMT - TiO2 Nanocomposite) was created. Analysis using Scanning Electron Microscopy (SEM) revealed that the modified TiO2 Nanocomposite was successfully dispersed into the Chitosan matrix and that the roughness of the Chitosan Nanoparticle - MMT- TiO2 Nanocomposites were significantly reduced. Moreover, X-Ray Diffraction (XRD) and Fourier Transform InfraRed (FT-IR) spectroscopy analyses indicated that the Chitosan interacted with TiO2 Nanocomposite and possessed good compatibility, while a ThermoGravimetric Analysis (TGA) of the thermal properties showed that the Chitosan-MMT-TiO2 Nanocomposites with 0.05% TiO2 Nanocomposite concentration had the best thermal stability. The Chitosan- MMT-TiO2 Nanocomposite exhibited an inhibitory effect on the growth of gram-positive and gram-negative microorganisms.

The goal of this study was to fully utilize sugarcane bagasse, an abundant residue from the Vietnamese sugar industry that is also known as a potential source of lignocellulosic. The biomass material was used as a raw material to produce cellulose pulp followed by a hydrogen peroxide bleaching process. On the one hand, the unbleached cellulose pulp was used to make paper sheets with basis weights of around 100 g/m2. The bleached cellulose, on the other hand, was chemically and mechanically transformed into nano cellulose via a limited hydrolysis procedure. The obtained nano cellulose possessed a high crystallinity of 80.11% and was used for paper sizing to improve the mechanical and barrier properties of the paper. The ability of sugarcane bagasse nano cellulose-coated paper sheets to produce biodegradable containers for food and beverage applications was investigated.

Hydrotreating heavy naphtha using highly active NiMo catalysts on walnut shell activated carbon (NiMo-WAC) nanocatalysts is a new technology for clean fuel production. In this research, pyrolysis of the walnut shell as a scalable, low-cost, and high-yield method was used to synthesize chemically activated carbon in the presence of ZnCl2, as activating agent. To enhance the catalytic conversion, walnut shell active carbon was functionalized with HCL, HNO3, and H2SO4 to prepare NiMo-WAC1, NiMo-WAC2, and NiMo-WAC3 respectively. These nanocatalysts were synthesized through the incipient wetness impregnation method and characterized by X-Ray Diffraction (XRD), Fourier Transform InfraRed (FT-IR) spectroscopy, Inductively Coupled Plasma-atomic emission (ICP) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Brunauer–Emmett–Teller (BET) surface area, Temperature-Programmed Desorption (TPD) and Temperature-Programmed Reduction (TPR) techniques. CHNS (Eager 300 for EA1112) was used to study elemental analysis of the walnut shell feedstock used for active carbon synthesis. Different operating parameters including temperature, pressure, LHSV, and H2/feed (heavy naphtha) ratio for hydrodesulfurization (HDS) reactions were explored by evaluating NiMo-WAC nanocatalysts catalytic activity. HDS of heavy naphtha with 2491 ppm of sulfur in the operation condition of temperature: 290 °C, pressure: 30 bar, H2/oil: 100 NL/L, and LHSV: 3.3 h-1 showed considerably higher activity of NiMo-WAC2 nanocatalyst, less than 10 ppm in the product, than NiMo-γAl2O3 as a commercial and reference catalyst, maximum 104 ppm in the product, and this is economically valuable.

Hydrotreating of heavy naphtha using highly active NiMo catalysts on Walnut shell Activated Carbon (NiMo-WAC) nanocatalysts is a new technology for clean fuel production. In this research, pyrolysis of the walnut shell as a scalable, low-cost, and high-yield method was used to synthesize chemically activated carbon in the presence of ZnCl2, as activating agent. To enhance the catalytic conversion, walnut shell active carbon was functionalized with HCL, HNO3, and H2SO4 to prepare NiMo-WAC1, NiMo-WAC2, and NiMo-WAC3 respectively. These nanocatalysts were synthesized through the incipient wetness impregnation method and characterized by X-Ray Diffraction (XRD), Fourier Transform InfraRed (FT-IR) spectroscopy, inductively coupled plasma-atomic emission spectroscopy (ICP), Field Emission Scanning Electron Microscope (FESEM), Brunauer–Emmett– grammed Reduction (TPR) techniques. CHNS (Eager 300 for EA1112) was used to study elemental analysis of the walnut shell feedstock used for active carbon synthesis. Different operating parameters including temperature, pressure, LHSV, and H2/feed (heavy naphtha) ratio for hydrodesulfurization (HDS) reaction were explored by evaluating NiMo-WAC nanocatalysts catalytic activity. HDS of heavy naphtha with 2491 ppm of sulfur in the operation condition of temperature: 290 °C, pressure: 30 bar, H2/oil: 100 NL/L, and LHSV: 3.3 h-1 showed considerably higher activity of NiMo-WAC2 nanocatalyst, less than 10 ppm in the product, than NiMo-γAl2O3 as a commercial and reference catalyst, maximum 104 ppm in the product, and this is economically valuable.

In this study, a new environmentally friendly method for the synthesis of technical Fenitrothion is offered. Apart from using ionic liquid as the innocuous and recoverable solvent, this methodology offers sonochemical-assisted synthesis. Technical Fenitrothion has been obtained from the reaction of 3-methyl-4-nitrophenol as a critical intermediate in this green method. According to this methodology, m-cresol is nitrated by ferric nitrate as the nitrating agent in the presence of triethyl ammonium nitrate ionic liquid as a recoverable protic solvent under ultrasonic irradiation, in short reaction time and high yield. Ionic liquid caused more para selectivity of nitration by steric hindrance through hydrogen bond formation with phenolic oxygen, which inhibited ortho substitution of the aromatic ring, and 4-isomer obtained as the major product. The developed process provided task-specific ionic liquid preparation from by-products and the possibility of recycling the ionic liquid for five consecutive runs, which has the benefit of eliminating waste products generated out of this procedure following green chemistry principles.

Regarding the importance of targeted delivery of pharmacies, a novel drug delivery system was designed by mesalazine (Mes) anchoring on Graphene Oxide (GO) modified with polyethylene glycol (PEG) to obtain 2.6 mmol Mes on 1 g of GO-PEG. The new compound was produced through esterification reactions of GO with PEG and subsequent esterification with Mes. The nano drug was characterized with common analysis methods including Raman, FT-IR, UV-Vis, Energy Dispersive X-ray, X-ray Diffraction, and Transmission Electron Microscopy. The in vitro Mes releasing from the composite was evaluated at two pHs of 3.5 and 7.4 for simulation of the gastric and intestine conditions. It was found that the compound is more stable in acidic media and slowly releases Mes at pH=4. The reason for this phenomenon is considered the ester bonds are produced in acidic media and have not been hydrolyzed in these conditions. The initial results of in vitro experiments indicated that the new drug would be a promising candidate for use in vivo.

The molecularly dispersed BiP1-xVxO4/SiO2 supported oxides, with x varying from 0 to 1, were prepared by impregnation of Bismuth, Phosphorus, and Vanadium on silica. Their structures have been characterized by different techniques: X-ray diffraction, Raman spectroscopy, Temperature-Programmed Reduction of catalysts in H2 (H2-TPR), and methanol oxidation reaction. This very sensitive technique provided us with relevant information on the nature of the active sites (acid-base and redox) on the surface of the catalysts. The results of the characterization show the structural evolution of the vanadium species of the isolated crystallites from V2O5 for x =0.3 and x =0.5, to BiVO4, with the disappearance of BiPO4, with the increase of the vanadium content from x=0.5 to x = 1. The oxidation of methanol showed the basic properties of the BiPO4/SiO2 catalyst, by the formation of carbon dioxide as the major product of the reaction. The substitution of phosphorus with vanadium promotes the formation of formaldehyde, confirming the presence of redox sites on these substituted catalysts. These catalysts were examined in the Oxidative dehydrogenation (ODH) of propane. For x ≥ 0.5, the dispersed BiVO4 exhibited significant activity in propane ODH than the BiPO4 and V2O5 crystallites, with good selectivity to propylene and acrolein, consistent with their high reducibility confirmed by H2-TPR, and the presence of redox sites shown by the oxidation of methanol. The catalyst with x = 0 was less selective for propylene due to the favorable combustion of propylene during its formation. Such an understanding of the intrinsic catalytic properties of the BiP1-xVxO4/SiO2 oxides and in particular, the BiPO4 and BiVO4 crystallites provides new information on the structural requirements of the propane ODH reaction, beneficial for the design of more efficient Bi-P-V-O based catalysts for propylene and acrolein production.

A large amount of sugar beet pulps are produced annually as waste which causes environmental pollution. However, the composition of sugar beet pulp indicates the possibility of producing several value-added products. In this study, high-quality α-cellulose was extracted from sugar beet pulp. The purity and optical properties of α-cellulose significantly affect its application in various industries, such as the production of napkins or a variety of papers. The bleaching step has a significant effect on the quality of cellulose. So bleaching conditions including the concentration of NaClO (4.5-1 % w/w), temperature (25-60 °C), and time (15-45 minutes) were optimized based on response surface methodology. The results showed good optical properties, low Kappa number, and high cellulose content (yield) could be achieved when the operating parameters were controlled. Severe bleaching conditions such as higher NaClO concentration or longer bleaching time caused cellulose oxidation and reduced efficiency. Optimal bleaching conditions for SBP were determined as 3.28% (w/w) NaClO at 25 °C for 45 minutes. These conditions led to the production of α-cellulose with a 69.38% of whiteness index, a Kappa number of 1.02, and a yield of 23.16%. The structure of the samples was investigated by SEM and FT-IR analysis. Therefore, the pulping and bleaching process has led to value-added products with industrial applications from sugar beet pulp.

The exploration of indigenous raw materials that are pure and simple to process for ceramics is a scalable option for locally-made ceramics products. This study involves the characterization of unexplored silica-rich sand deposits at Iva-pottery, Enugu North local government area in Enugu state Nigeria for their ceramic industrial potential. The physicochemical properties of Iva-pottery silica-rich sand were determined. The crystalline phase components and elemental compositions of the oxide were investigated with an X-ray diffractometer and an X-ray fluorescence spectrophotometer respectively. The silica was used in ceramics composition as a filler and glaze formulation as glass former.  The results obtained showed mainly a siliceous crystalline phase with a minor amorphous phase and contains 74.55% SiO2, 13.02% Al2O3, and 0.55% Fe. The grain size in the raw form is in the range of 0.18 mm to 0.075 mm (100 mesh to + 200 mesh range) without involving ceramic raw materials processing equipment such as a ball mill as well as a high percentage of alumina (13.02) contents as compared to conventional silica with alumina 0.02% to 0.5% range. The high alumina that forms mullite at sintering temperature brings about a low thermal coefficient and hence, suitable chemical stability and resistance to thermal shock.  These rare qualities make the Iva-pottery silica-rich sand an emergent material suitable for glaze formulation and filler in ceramic bodies. Thus, it is recommended that the Iva-pottery silica-rich sand deposits in their raw form be exploited for the formulation of varied glaze temperature ranges and also for the refractory industry. Iva-pottery silica-rich deposits in their raw form, do not meet the requirements of high tech- ceramics applications.

In this research, wheat bran and waste coffee without any chemical treatment are used as low-cost biosorbents for the removal of zinc ions from an aqueous solution. Parameters such as contact time, adsorbent dose, initial concentration, and pH were studied. To describe adsorption equilibrium, Langmuir and Freundlich isotherms were used. Experimental results confirm that the adsorption of zinc ions on waste coffee fits well with the Langmuir isotherm while Freundlich isotherm is a better fit for wheat bran. The maximum capacity of zinc ions adsorbed, with the Langmuir model for wheat bran is a bit higher (qmax= 9.01 mg/g) than waste coffee (qmax= 6.41 mg/g). The thermodynamic parameters, enthalpy (ΔHo), entropy (ΔSo), and Gibbs free energy (ΔGo), provide that the adsorption process is exothermic, spontaneous, and favorable for both used biosorbents. The structure of both biosorbents was analyzed by the pH of the point zero charge (pHPZC) and FT-IR spectra.

Our work is related to the use of adsorption as an effective physical method for water treatment contaminated with toxic dyes generated by various industries. We focused on the adsorption/removal of Methyl Orange (MO) dye from an aqueous solution using a new hybrid organometallic-based material constructed via In-Situ polymerization of Zinc-building units connected by coordination bonds to 4,4'-Carbonyldiphthalic acid (H4CDPA) as a flexible multidentate organic ligand under solvothermal conditions with an amount of Maghnite-H+, an acid-exchanged montmorillonite clay to obtain Zn-CDP/Mag-H+ extremely stable thermally with an onset temperature of degradation upper to 460°C as shown by ThermoGravimetric Analysis (TGA). The structure of this material is confirmed by Fourier Transform InfraRed (FT-IR) spectroscopy and X-Ray Diffraction (XRD). The effect of different parameters such as adsorbent mass, initial dye concentration, contact time, and pH of solution on the adsorption capacity of this material is investigated using UV-Visible spectroscopy. The kinetic study shows that the adsorption process of MO is very fast and well described by the pseudo-second-order model. The adsorption isotherms of the adsorbent/adsorbate systems are in agreement with the Langmuir equation showing an adsorption capacity of 147.05 mg/g for this material. The thermodynamic parameters calculated at various temperatures indicate that MO adsorption on Zn-CDP/Mag-H+ is an endothermic reaction (∆H° > 0) and spontaneous (∆G° < 0) process.

Several methods have been implemented to eliminate antibiotics from wastewater. Serious issues are associated with the disposal of antibiotics into the aqua resources, resulting in the contamination of these systems. The utilization of natural adsorbents, like clays and naturally derived adsorbents, has been tried to solve this problem. Red mud was examined as an adsorbent for multiple pollutants in this regard. This work reports the utilization of the Iraqi red mud as a priceless and effective adsorbent for eliminating the Rifampicin antibiotic from its aqueous solution after being activated with 10 % HCl to enhance its surface area. BET surface area, Field Emission Scanning Electron Microscope, Fourier infrared spectroscopy, Energy Dispersive X-ray, and X-ray diffraction of both the raw mud and its activated sample were determined. The BET surface area of the Iraqi red mud rose from 30.99 m2/g to 60.96 m2/g because of the acid treatment. The influence of the adsorption operative factors, including the solution pH, Rifampicin initial concentration, adsorbent dosage, temperature, and contact time, on Rifampicin elimination by the activated red mud, was inspected. The typical adsorption capacity of Rifampicin by the activated red mud was 217.93 mg/g utilizing 0.20 g of the activated red mud at 328 K for 180 minutes contact time in an acidic medium (pH = 4.0). The Langmuir model best described the adsorption behavior of Rifampicin over the activated red mud due to its higher correlation coefficient value (R2 = 0.9928) than that of the Freundlich model (R2 = 0.9117). Rifampicin adsorption by the activated red mud followed the pseudo-second-order kinetic model. Thermodynamic analysis revealed that the adsorption of Rifampicin favored high temperatures, suggesting that the adsorption is endothermic in nature and spontaneous. Finally, the activated red mud is an eco-friendly and reusable adsorbent to remove antibiotic pollutants.

This study aimed to investigate the effect of type of solvent (1: ethanol and 2: water), time (3, 6, 9 min), and power (100, 200, 300 W) of ultrasound assist in the extraction rate of flavonoids, anthocyanins, Ic50 as well as the antimicrobial effect of the extract of Punica granatum. Var. Pleniflora (PGP). In order to design treatments, analysis, and optimization of dependent variables the full factorial design is used.  The result of multiple optimizations of independent variables revealed that the highest amount of flavonoids in PG) extract (9.0502 mg/ml) and the amount of anthocyanin (5.3669 Μmol/g) and the lowest Ic50 value or the highest rate of free radical scavenging in (PGP) (8.0452 mg/ml) with 88.97% desirability were observed at 300 w for 9 min by using methanol as a solvent. The highest mean values of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of PGP extract obtained by ultrasound pretreatment were 625 and 3750 μg/ml respectively against Clostridium perfringens. The optimized predicted treatment by ultrasound pretreatment had a greater antimicrobial effect on Staphylococcus aureus with the largest diameter of the growth inhibition zone (14 mm) compared to E. coli and C. perfringens. The results showed that the extract obtained from PGP could be introduced as an antioxidant source in marketable foods

This study investigated the effects of the microencapsulation of Lactobacillus acidophilus La-5 along with Spirulina platensis on bacterial survival in sour cherry juice containing synbiotic capsules. S. platensis powder was used as a prebiotic and the microencapsulation of bacteria and S. platensis was conducted using the spray dryer method. S. platensis and bacteria were encapsulated in maltodextrin and cross-linked alginate. Bacterial survival, thermal tolerance, morphology, efficiency, and resistance under simulated gastric and intestinal conditions in sour cherry juice were examined. The results showed a decrease in probiotic bacterial death in sour cherry juice containing bacteria and algae encapsulated at 4°C on the 28th day of storage (7.9 ± 0.10) (Log CFU/mL) as well as an increase in temperature resistance in fruit juice containing bacteria capsules and S. platensis. The results of Scanning Electron Microscopy (SEM) analysis revealed that the capsules contained L. acidophilus La-5 and S. platensis with round shapes and had an average diameter of 12.80 ± 1.43 µm. The examination of bacterial encapsulation efficiency indicated that the highest and lowest values for bacteria encapsulated with Spirulina and bacteria capsules without Spirulina were 81.9% and 79.86%, respectively. In addition, organoleptic analysis of sour cherry juice at 4°C and at the end of storage duration in the refrigerator demonstrated the highest general acceptance (4.60 ± 0.10) for the juice, containing bacteria and Spirulina compared to other bacterial groups (p<0/05). L. acidophilus La-5 capsules containing Spirulina showed the largest viability during the 0-10 min period and 60-80°C temperature (p<0/05). Moreover, bacteria encapsulated with Spirulina exhibited the highest survival rate under simulated gastric and intestinal conditions over a 0-120 min incubation time. Overall, using S. platensis as a prebiotic can significantly stimulate the growth of L. acidophilus La-5 as a beneficial probiotic, which results in the production of healthier and more nutritious sour cherry juice.   

The flow behavior of bubbles in the expansion of the microchannel is studied. Four stable flow patterns are observed: Double-Layer-Bubble Coalescence (DLBC), Hamburger-Double-Layer-Bubble Coalescence (HDLBC), Hamburger Flow Coalescence (HFC), and Non-Coalescence Hamburger Flow (NCHF). With the increase of gas velocity, the flow pattern changes gradually from DLBC to HDLBC, HFC, and UHFC. The experimental results show that the liquid film drainage time increases with the bubble length. The location of bubble coalescence is away from the inlet with the increase of bubble length and bubble velocity but moves towards the inlet with the increase of liquid slug length. A prediction equation of bubble coalescence position is proposed, which has a good prediction effect.

Proton-exchange membrane fuel cells consume hydrogen and air and have high efficiency and power density. The present study three-dimensionally investigates the performance of PEMFCs with different geometries under different operating conditions. The computational fluid dynamics approach was adopted to solve the governing equations. In CFD, the finite volume method is employed to discretize and solve equations. A serpentine gas injection channel and a parallel gas injection channel of the same size were examined. The proposed approach was validated by simulating the base model at 0.6 V and three reference current densities. The present work primarily sought to improve the performance of PEMFCs. Also, the concentration diagram indicated that the water concentration rose on the cathodic side, implying reasonable water transfer management was reasonable. Moreover, the oxygen concentration declined on the cathodic side. The serpentine model was found to have a higher current density and output power than the parallel model. Liquid water production was lower in the serpentine model than in the parallel model. This prevented immersion and fuel cell interruption. Water accumulation in the middle of the PEMFC with the parallel channel hindered uniform temperature and current density distributions. The parallel model underwent a lower pressure drop than the serpentine model. Therefore, lower power was required to pump the gases through the parallel channel. A rise in the reference current density reduced liquid water production and overpotential and improved the current density distribution and temperature distribution in both serpentine and parallel models.

Production of a homogeneous solution is of great interest for Lab-on-a-Chip (LOC) applications. Since the fluid flow in microchannels is laminar, the LOC devices have low mixing efficiency in passive mixers. The present study proposes a novel electroosmotic micromixer in which the electrodes have a fin-shaped structure in the mixing chamber. In other words, the combined effect of obstacle and electro-osmosis is evaluated. The effect of various parameters such as electrode angle, electrode height, inlet velocity, alternating current, and frequency on mixing index and pressure drop is investigated. Vortices are formed around the electrodes due to the applied electric field and their fin-shaped structure. It is revealed that the mixing index is an increasing function of applied voltage. The results demonstrate that there is an optimal value for the parameters, including frequency, electrode height, inlet velocity, and electrode angle. An increase in the mixing efficiency is accompanied by an enhancement in the pressure drop. It is revealed that the maximum efficiency is achieved when the electrode height is 5 μm and the electrode angle is 60°. The coefficient of performance of the proposed micromixer is more than that of the reference mixer when the electrode height is 2.5 μm and the electrode angle is 90°.

Myrtus communis L. (Myrtle) is an evergreen shrub and its fruit is used in traditional medicine in hypoglycemic, oral, and stomach disease therapy. To the best of our knowledge, there is no report on microwave drying of it. Therefore, this study is aimed to evaluate the effect of microwave power and fruit thickness on drying kinetics, effective moisture diffusivity, activation energy, specific energy consumption, and quality characteristics of Myrtus communis L.. Thus, four thicknesses (5, 7, 9, and 11 mm) of the fruit were dried at microwave power levels of 450, 600, and 750 W. The kinetics study revealed that the Midilli et al. model exhibited the best microwave drying behavior of the samples. Moreover, increasing microwave power and decreasing fruit thickness resulted in a substantial (P<0.05) reduction in drying time and an increase in drying rate. Fruit thickness also showed a significant effect (P<0.05) on effective moisture diffusivity and specific energy consumption, which ranged from 0.453×10-7 to 8.91×10-7m2/s and 6.98 to 18.13 MJ/kg water, respectively.  In addition, the less fruit thickness, the more moisture diffusivity, and the less activation energy. The calculated activation energies were in the range of 11.46 to 21.76 W/g. Moreover, as the thickness of the fruit was reduced and the microwave power was increased, the shrinkage ratio of the samples was reduced and their rehydration abilities were enhanced. Finally, it was determined that a microwave power of 750 W and a fruit thickness of 5 mm made better results in terms of quantity and quality parameters. a significant effect (P<0.05) on effective moisture diffusivity and specific energy consumption, which ranged from 0.453×10-7 to 8.91×10-7 m2/s and 6.98 to 18.13 MJ/kg water, respectively. In addition, the less fruit thickness, the more moisture diffusivity, and the less activation energy. The calculated activation energies were in the range of 11.46 to 21.76 W/g. Moreover, as the thickness of the fruit was reduced and the microwave power was increased, the shrinkage ratio of the samples was reduced and their rehydration abilities were enhanced. Finally, it was determined that a microwave power of 750 W and a fruit thickness of 5 mm made better results in terms of quantity and quality parameters.

 In this work, the real case study of the energy quality of the natural gas liquid recovery plant 800 is evaluated via exergy, exergy economy, and exergy environmental methods. The corresponding simulation is carried out using Aspen HYSYS V10 software and Matlab. Sensitivity analysis will evaluate energy consumption, environmental impact, and the economics of inefficient equipment. The exergy analysis results show that the compressor (K103) and the heat exchanger (E101) with the highest exergy destruction are 510 and 629 kW, respectively. Improving the performance of these equipment can reduce exergy destruction and increase exergy efficiency. Furthermore, the results indicate that the main improvement priority belongs to the compressor (K103). According to the results of the exergoeconomic evaluation, the maximum value of the exergoeconomic factors belongs to the heat exchanger (E103). It should be replaced by a cheaper one. Furthermore, E100 and K102 have the potential for economic improvement in terms of their high exergy destruction and the relative cost difference. Furthermore, their low values of exergoeconomic factors show dominance in the exergy-related cost part. Improving the performance of these devices will significantly reduce the overall cost rate by up to 40%. The results show that the main improvement priority based on the exergoeconomic concept belongs to the compressor (K102). The highest value of the exergoenvironmental factor belongs to the heat exchanger (E-103) by 99%. This shows its high LCA environmental impact. The total impact rate may be reduced by up to 97 percent by optimizing the equipment's operating and maintenance parameters. Environmental results show that E101 and P100 have the potential for improvement. Improving the performance of these devices will significantly reduce the overall environmental impact by up to 40%. Furthermore, the main priority for improvements based on the exergoenvironmental concept belongs to the heat exchanger (E101).

An Eulerian–Eulerian-based two-dimensional mathematical modeling approach for bubbling fluidized bed gasifier using FLUENT has been proposed to transfer energy, momentum, and mass between two phases namely solid and gas together with the application of the kinetic theory of solid particle flow. The modeling equation involves eight homogeneous and five heterogeneous reactions kinetics. The eddy dissipation model of FLUENT has been used to incorporate homogeneous reaction kinetics and a user-defined code has been developed that describes the kinetics of heterogeneous reactions. The simulation result shows that the exit syngas composition is in line with the experimental one and has a maximum error of around 4.05% for CO and 2.68% for hydrogen. This model has been used to study the variation in hydrogen concentration in the syngas to maximize hydrogen production based on different operating and design parameters.

Nano particles-based catalysts are additives that can be used in green fuels to improve the characteristics of an engine. In the present study, non-edible Aegle marmelos (AM) de-oiled seed cake biomass is used for the production of pyrolysis oil. The copper oxide (CuO) nanoparticles are prepared via the Sol-Gel process and categorized by Scanning Electron Microscopy (SEM), Energy-Dispersive X-Ray Analysis (EDAX), and Fourier Transform InfraRed (FT-IR) Spectroscopy. The CuO nano particles are mixed with pyrolysis oil-diesel opus at a fraction of 30 and 50 ppm. The Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS) tool is employed to attain the optimum engine process parameters. The correlation between cylinder head temperature and exhaust emission was concluded by using an innovative approach to thermography image processing. The outcomes of experimental, TOPSIS, and image processing revealed that modified fuel opus emitted a lesser amount of carbon monoxide, oxides of nitrogen, and unburned hydrocarbon compared with diesel but augmented CO2 (Carbon dioxide) emission. It is found that higher CO2 emission is apparent for the dynamic combustion process. This study confirms that AM bio-oil opus is an affordable alternate fuel for diesel engines for a clean and green environment.

Kalman filter is a classic iterative estimation technique widely used to estimate states and parameters of linear dynamic systems with white Gaussian measurement and process noises. However, if the measurement noises are predominant, resulting in a poor signal-to-noise ratio, the estimator fails to provide allowable error covariance and optimal state estimation. In such circumstances, to enhance the estimation accuracy, measurement constraints need to be incorporated into the estimation routine. Through this work, a Quadratic Program-based Constrained Kalman Estimation (QP-CKE) estimation sequence is proposed and developed to handle the additive measurement noise constraints. This is implemented by incorporating a deconvoluted quadratic program with a modified Kalman estimation paradigm to handle the constraint cost function. Composition estimation in a laboratory binary distillation process for ethanol-water mixture separation under steady-state operating conditions is used as a case study. Noise augmented Two Input Two Output (TITO) linearized dynamic model of the process is established by inferring Gaussian distributed tray temperature measurements and mixture vapor-liquid equilibrium data. The performance of this new estimator is tested for top and bottom composition estimation for step input excitation for reflux rate and reboiler power inputs under feed flow disturbances and the results are compared with that of conventional Kalman and Q adaptive Kalman estimators. The performance of the proposed estimator proves to be competent with reasonable computational speed and improved estimation accuracy. Also, relative volatility and vapor-liquid equilibrium trends are derived from estimated tray composition data, and results are found in good relevance with that of the experimental data.

In this work, the corrosion rate and inhibition efficiency of oleic imidazoline and 2-mercaptobenzimidazole in 1 M HCl were studied on carbon steel samples. The corrosion efficiency of oleic imidazoline and 2-mercaptobenzimidazole at a concentration of 75 ppm was 85.8 and 82.9%, respectively. In addition, a mixture of these reagents at a ratio of 1:1 showed enhanced corrosion inhibition. The optimal concentration of the proposed mixture of reagents was 75 ppm. In this case, the inhibition efficiency was 97.8% (by weight loss method). The synergistic inhibition effect between the components of the proposed mixture was obtained 15.9%. Meanwhile, by increasing the temperature from 298.15 to 373.15 K, the corrosion inhibition of the reagents was not considerably decreased, which was associated with their complete adsorption on the surface of the carbon steel samples. The adsorption of inhibitors followed the Langmuir isotherm. The values of free energy of adsorption in the presence of the corrosion inhibitors ranged from -31.6 to -32.62 KJ/mol, which indicated both physisorption and chemisorption features. Moreover, the results of electrochemical impedance spectroscopy and potentiodynamic polarization tests confirmed that the mixture of reagents at the ratio of 1:1 has a significantly higher inhibitory ability compared to each of the reagents alone. The used reagents behaved as a mixed-type inhibitor and affected both cathodic and anodic reactions.

CP47 is one of the essential components of photosystem II (PSII) in green plants, green algae, and cyanobacteria; which is involved in the light reactions of photosynthesis. Various studies have shown that the binding of the extrinsic protein of 33 kDa (PsbO) to the large extrinsic loop of CP47 (E loop) is an essential photoautotrophic activity of the PSII complex. Moreover, the deletion of the amino acids between Gly-351 and Thr-365 within loop E failed to assemble stable PSII centers. In this study, using computational methods, the effect of Phenylalanine (Phe) mutation at position 363 on Synechocystis sp. PCC 6803 CP47 was investigated and then the mutant model was compared with the native one. Because the experimental 3D structure of Synechocystis sp. PCC 6803 CP47 and PsbO proteins are not available in the Protein Data Bank (PDB), the 3D structure of these proteins was modeled by homology modeling. After refining and energy minimization, the quality of protein geometry was assessed by different criteria such as PROCHECK and ProSA. Then, structural analysis of mutant and native models was performed with Molecular Dynamic (MD) simulation and docking method. The analysis of results obtained from MD simulation shows that F363R mutation affects the flexibility of some regions and especially leads to an increase in mutation region and changes the conformation of CP47. In addition, the results of docking studies indicate that F363R mutation can decrease buried surface area (BSA) at the interface region and decrease the binding energy of CP47 and PsbO. These data reinforce our hypothesis that an increase of flexibility at the position of F363 in the large extrinsic loop of CP47 may be an important factor in reducing interaction between CP47 and PsbO extrinsic protein and then water oxidation. oxidation.

The current study suggested a thermal treatment as a necessary proactive step in improving the adsorption capacity of bio-waste for contaminants removal in wastewater. This approach was based on the experimental and histological investigation of biowaste pod shells. This investigation showed that these shells composed of parenchyma cells that store secondary metabolites compounds produced from cells were exhibited in the present study. The results also reported that these compounds are extracted directly from the cells as soon as they are exposed to an aqueous solution, hampering their use as an adsorbent material. The increase in the weight of bio-waste adsorbent at unit liquid volume increases the production of secondary metabolites compounds under normal conditions. While thermal conditions accelerate the exit of these compounds from their storage places. After suggested thermal processing, the bio-waste was examined for azo dye removal under different operational conditions (adsorbent weight (1, 0.1 g), contact time (24 and 48 h), and temperature (30, 40, 50, and 60  oC). In general, the experimental data showed a good improvement in adsorption potential. The results presented clearly that the increase in temperature has a positive effect on the performance of pollutant removal. The maximum adsorption capacity was 0.035833 mol/g at a temperature of 40°C, and 0.036417 mol/g at a temperature of 50°C. This behavior may be counterproductive with high temperatures as a result of the release of more secondary metabolite compounds. For other operating conditions, increasing the concentration of the pollutant also improves the efficiency of the process, while this efficiency decreases with the increasing weight of the adsorbent material. For example, the removal capacity was (0.000275, 0.00675 mol/g) with 1 and 0.1 g of the adsorbent weight, respectively. Finally, the present study concluded that the adoption of thermal pre-treatment technology for bio-mass waste is a necessary step in improving the adsorption processes. the adsorption processes.

An experimental approach for the estimation of average shear rate (γav) in a stirred tank bioreactor has been proposed for the turbulent flow regime. Based on the proposed methodology, the correlation for the estimation of γav was obtained as a function of agitation speed (N), superficial gas velocity (Vs), and the rheological properties of the non-Newtonian fluids. The γav estimated by the present method was found to be within the range of values calculated by correlations available in the literature. The γav increased with the increase of agitation and sparging in all the conditions tested. The correlation derived in the present work helps in the estimation of γav as a function of bioreactor geometry along with physical conditions (N and Vs), and rheological properties (n and K) of non-Newtonian fluid in commercially available stirred tank bioreactor.