Iranian Journal of Chemistry and Chemical Engineering
Volume:41 Issue: 10, Oct 2022

Flutamide is used with a luteinizing hormone-releasing hormone agonist, a type of hormonal injections such as leuprolide, goserelin, or triptorelin to treat certain types of prostate cancer. Flutamide is in a class of medications called nonsteroidal antiandrogens. Ethyleneimine  is used in polymerization products; as a monomer for polyethyleneimine; as a comonomer for polymers and in paper and textile chemicals, adhesives, and binders. This study applied ethyleneimine to modify Flutamide as an anti-cancer drug. Therefore, an investigation of the adsorption behavior and electronic properties of carbon nanotubes and nanocones against flutamide @ ethyleneimine was carried out by calculation of the density functional theory. The N atom of flutamide @ ethyleneimine helps its adsorption on the nanotubes and nanocones, showing adsorption energies of around - 30.1 and - 20.5 kcal/mol, correspondingly. Chemical activities of the nano complexes were specified through electronic parameters such as electronegativity, electron affinity, softness, and hardness. All calculated data obtained good behavior of flutamide @ ethyleneimine with nanotubes and nanocones adsorption as carriers.

In this work, Aspergillus niger pectinase was immobilized on hydrophilic silica aerogel and its magnetic nanocomposite by adsorption method, and the performance of these supports in pectinase immobilization was compared. Physical and chemical properties of supports and the immobilized pectinase were characterized by Brunauer–Emmett–Teller (BET) analysis, Field Emission Scanning Electron Microscope (FESEM), Fourier Transforms InfraRed (FT-IR) spectroscopy, and Vibrating Sample Magnetometer (VSM). The results showed that the pectinase was successfully immobilized onto both supports. The kinetics of the immobilized pectinase followed the Michaelis–Menten model. The maximum reaction rate (Vmax) and affinity of immobilized pectinase to the substrate (Km) in pure silica aerogel were higher than in magnetic silica aerogel. The maximum monolayer adsorption capacity of the pure silica aerogel (qmax=129.17 mg/g) was higher than magnetic silica aerogel (qmax=53.42 mg/g) based on Langmuir isotherm. The thermal stability of the immobilized pectinase was improved toward free pectinase. The reusability tests of immobilized pectinase showed that magnetic silica aerogel had better operational stability than pure silica aerogel because of higher mechanical resistance and retained 57% of its initial activity after 10 repetitive cycles.

In this work, Ni NPs have been in-situ synthesized using hydrazine as a reducing agent and immobilized on nanofibrillated cellulose (Ni/NFC) and magnetic nanofibrillated cellulose (Ni/Fe3O4@NFC) as green supports. The structure and morphology of the Ni/Fe3O4@NFC nanocomposite clarified high purity single-phase spherical-shaped Ni nanoparticles of about 30 nm distributed on the surface of nanocellulose as compared to the larger size of star shape particles in Ni/NFC. The catalytic activity of both nanocomposites was investigated for the reduction of 4-nitrophenol (4-NP), Methyl Orange (MO), and Methylene Blue (MB). The results demonstrated high catalytic efficiency toward the removal of water pollutants in a short reaction time. The reduction rate constants (k) of freeze-dried Ni/Fe3O4@NFC catalyst were 30 ×10-3 s-1, 17.3×10-3 s-1, and 6.9 ×10-3 s-1, for 4-NP, MO, and MB respectively, which were higher than those of synthesized Ni/NFC and other reported Ni-based catalysts. Moreover, the catalyst could be easily magnetically recoverable and reusable in other cycles.

Phase Change Materials (PCMs) can be used as thermal energy storage systems in the form of latent heat. These materials are commonly enclosed in a suitable container, in order to prevent leakage of the molten PCM into the surrounding environment. In this study, palmitic acid and polyaniline were used as PCM and polymeric shell, respectively, to prepare a form stable composite. SiO2 nanoparticle was added to the composite to improve the thermal characteristics of the composite. The structure and morphology of the prepared form stable nanocomposite were investigated by Fourier Transform InfraRed (FT-IR) spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), and X-Ray Diffract meter (XRD) tests. It was found that the synthesized nanocomposite was fabricated in the form of relatively smooth and compact spherical particles with a size of about 500 nm. Thermal properties of the prepared nanocomposite containing different concentrations of SiO2 nanoparticles were determined using Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA) tests. It was found that the melting temperature and thermal conductivity of the polyaniline/palmitic acid composite increased by about 16% and 62%, respectively, when combined with 2 wt.% SiO2 nanoparticles. The obtained results revealed that the polyaniline/palmitic acid/2 wt.% SiO2 nanocomposite can be considered a suitable option for thermal energy storage applications.

While one of the valuable approaches to obtaining a heterogeneous catalyst is supporting them on a high surface area supports, the strategy mainly suffers from the low number of chelating agents on most of the supports to grip the metal cations catalysts. Therefore, loading multidentate compounds susceptible to binding with metal cations is a potent strategy to improve the catalyst stability on the support. In this report, metformin as a multi-dentate ligand was bonded onto graphene quantum dots as a high aspect ratio compound to afford new support susceptible to chelating Co(II). Deposition of Co(II) on graphene quantum dots modified with metformin gave a new sustainable heterogeneous catalyst that was highly active in the oxidation of alkyl arenes. The reactions were performed in solvent-free conditions at 80 ºC with high conversions up to 96%. The organometallic compound is applicable as a recoverable heterogeneous catalyst with recyclability up to 6 times. The modification of graphene quantum dots with metformin also can gain more attention from medicinal researchers.

The present work deals with the synthesis, spectral characterization, DFT calculations, and catalytic activity of the new Hg(II) complexes derived from indazole ligands. The o-amino-ketones were obtained from the reduction of 6H-isoxazolo[4,3-e]indazoles as new heterocyclic ligands. Coordination of the ligands to Hg(II) cation led to the formation of new Hg(II) complexes. The IR, mass, and NMR spectra as well as the elemental analyses confirmed the structures of the new complexes. Furthermore, the DFT calculations at the B3LYP/6-311+G(d,p) level were used to gain further insight into the geometry of Hg(II) complexes. The catalytic activity of Hg(II) complexes as heterogeneous catalysts was studied for the synthesis of biologically active 3,4-dihydropyrimidin-2(1H)-one C5 ester (DHPMs), using classical Biginelli reaction followed by transesterification transformation. The results showed that the presented method gave the products good to excellent yields at reduced reaction time, which might be owing to the increased reactivity of the reactants on the surface area of Hg(II) complexes.

IIn the present study, a Pt(II) complex including 4-Bromo-2,6-bis-hydroxymethyl-phenol (BBHMP) and nicotinamide (NA) was synthesized and structurally analyzed by using spectral and thermal analysis methods. BBHMP and its Pt(II) complex in the presence of BBHMP and NA were investigated for their antimicrobial, cytotoxicity, gene expression, and antioxidant properties. The antimicrobial activity results showed that the platinum complex displayed a significant effect against Staphylococcus aureus and Candida albicans. The cytotoxicity of BBHMP and platinum complex were determined against human prostate adenocarcinoma (DU145) and breast (MCF7) cancer cell lines by applying the MTT assay. Cytotoxicity results suggested that the Pt(II) complex exhibited moderate cytotoxicity against the growth of these cancer cell lines when compared with the reference drug cisplatin is more effective than free BBHMP and NA. Gene expression results proved that the Pt(II) complex is a special bioactive chemical constituent and potential anticancer agent. The results obtained showed that the complex had highly inhibitory effects on gene expression. In addition, Pt(II) complex also displayed effective antioxidant activity.

In the present study, the Schiff base was synthesized [1,1'-((1E,1'E)-((4,5-dimethyl-1,2-phenylene)bis(azanylylidene))bis(methanylylidene))bis(naphthalen-2-ol) ] derived from the reaction of 2-hydroxy-1-naphtha-aldehyde with, 4,5-Dimetyl-1,2-penylenediamine for 4hr. and yield was 90.09%. The prepared compound was identified by C.H.N, UV-Vis, FT-IR 1H–NMR, and mass spectroscopy and was studied also theoretically using Gaussian 09 software based on the DFT method at B3LYP/6-31G (d,p). Quantum chemical calculations were performed to provide further insight into the inhibition efficiencies that were conducted experimentally. The weight loss method was used to measure the efficiency of the prepared compound as a corrosion inhibitor in an acid medium. It was found that the inhibition efficiency was increased with decreasing temperature and the concentration increase of synthesized Schiff base and the highest inhibition efficiency was obtained at an optimum concentration of (1×10-3 M) for inhibitor at 298 K. Moreover, it was found that the adsorption process of the inhibitor on the surface of the brass is obeyed by the Langmuir isotherm of adsorption. The value of the free energy change was found to be -28.28 kJ/mol, which indicates that the prepared compound adsorbed on the surface of the metal. The antioxidant activity of the prepared Schiff base was investigated on the basis of the radical scavenging effect of 1,1-diphenyl-2-picryl-hydrazyl (DPPH)-free radical activity was also studied. The ligand (S1) exhibited excellent activity.

The corrosion inhibition effect of Mentha spicata extract has been investigated for mild steel in an acidic medium by using weight loss and thermometric methods. Qualitative and Quantitative analysis of the extract was carried out using GC/MS analysis. Two major phytochemical components were identified by their mass spectra and retention indices. The inhibition capacity of Mentha spicata extract observed was carried at different temperatures (303 K, 313 K, 323K, and 333 K) which were found to increase with increasing concentration but decrease with increasing temperature. As the extract components got adsorbed on the metal surface, inhibition efficiency also increased and finally reached 86.01% at 303 K. The adsorption isotherm and free energy values were also calculated. Results have demonstrated that Mentha spicata is a mixed-type of corrosion inhibitor. Surface analysis by SEM documented the formation of a protective layer on the mild steel surface. Quantum chemical parameters such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), energy gap (ΔE), dipole moment (µ), and Total Energy (TE) were calculated. Quantum chemical calculations were also discussed to support the experimental data and the adsorption of inhibitor molecules onto the metal surface. It has been found that the extract acts as an effective corrosion inhibitor for mild steel in a hydrochloric acid medium. The results obtained show that Mentha spicata extract could serve as an excellent eco-friendly green corrosion inhibitor.

Fruit juices are important drinks, which are a rich source of water, vitamins, minerals, and other nutrients. Juice processing can affect its physicochemical properties and, therefore, change its nutrient value. One of the most important processes in juices is their clarification and concentration. Today, membrane processes such as microfiltration, ultrafiltration, nanofiltration, electrodialysis, membrane distillation, and osmotic distillation are used as new methods for concentrating and clarifying juices. The application of membrane processing has a significant effect on the physicochemical properties of juices such as pH, total solids, color, acidity, vitamins and minerals, phenolic compounds, and antioxidant activity. In this review, the effect of several membrane separation methods (microfiltration, ultrafiltration, nanofiltration, electrodialysis) on the physicochemical properties of fruit juices will be evaluated. Some membrane processes increase the pH of the juice and some do not change this parameter. The membrane clarification process reduces the Total Soluble Solid (TSS), turbidity, polyphenols, and antioxidant activity of fruit juices with different values. In addition, this process can completely remove the suspended solids from fruit juices. Most researchers have suggested that membrane clarification enhances the color value of juices. The effect of membrane processes on the number of organic acids and minerals depends on the type of juice, the type of membrane process, and the type of acid and minerals.

The Pd composite membranes were fabricated by an improved electroless plating procedure. The wetness-impregnation technique was applied for ceramic substrate activation. The adsorption Pd complex on the γ-AlOOH or γ-Al2O3 layer was studied in this work. The obtained results showed that the Pd complexes on the γ-AlOOH layer adsorbed more than the γ-Al2O3 layer. Additionally, the effect of Pd precursor concentration on substrate loading was investigated. The rate of palladium deposition increases at high Pd concentrations. The resulting membrane was characterized by XRD and SEM-EDX analysis. Furthermore, permeation fluxes of the as-synthesized membrane were evaluated for various gases at different H2 Pressure differences. The membrane permeance was determined to be 6.8×10−7 mol/m2.s.Pa at 798 K and 1 bar under pure hydrogen. The hydrogen permeance and selectivity of hydrogen relative to other gases (CH4, CO2, CO, and N2) were evaluated at 773 K. All gases exhibited dilution and inhibiting (especially CO) effects on hydrogen permeation. The prepared membrane does not seem damaged as the permeability recovered after treatment with pure hydrogen.

The effect of pH and the amount of Ca(OH)2 on the precipitation of boron from Eti Maden Kırka Boron Operations’ wastewater that contained 2752 ppm boron was investigated. It was observed that control of pH was the most important parameter and stepwise addition of Ca(OH)2 after adjustment of pH improved the precipitation. The best result was obtained in the two-stage addition of Ca(OH)2 with the initial control of pH and additional use of aluminum sulfate in the second stage which helped both in the reduction of pH and coagulation. Under these conditions, it was possible to lower the boron content in the wastewater to 250 ppm.

Mercury is one of the most important heavy metal elements of environmental pollution, and it is very important for its control. MesocCllular Foam (MCF) silica was prepared by hydrothermal method, and the prepared material was characterized by Powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), 77 K low-temperature nitrogen gas adsorption-desorption. Herein, the authors aimed to improve the adsorptive performance of MCF against mercury ions through a functionalization using disodium ethylenediaminetetraacetate (EDTA-Na2). Our novel material was then used in the batch adsorption of Hg2+, where the maximum conditions were reached after 35 minutes of contact time at pH 3 with the adsorbent weight of 0.1 g. The maximum adsorption amount of Hg2+ in the aqueous phase was 139.64 mg Hg2+ / g (modified MCF). The maximum desorption ratio of Hg2+ was 75.23% achieved by using 0.1 mol/L hydrochloric acid solution. The process for the adsorption of Hg2+ conforms to the quasi-second-order adsorption kinetics and Langmuir adsorption isotherm. The results of the low-temperature N2 adsorption-desorption curve at 77 K showed that Hg2 + had entered the MCF pore channels. This novel material is effective in removing Hg2+ from the water medium via batch adsorption.

In the present work, iron-doped particle Carboxymethylchitosan nanocomposite cross-linked with epichlorohydrin (CMC-EPC/INC) were prepared, by a chemical precipitation method, characterized and evaluated for the removal of As(v) from an aqueous solution. The adsorbent was characterized by FT-IR, XRD, and SEM. Key parameters, including adsorbent dosage, pH, temperature, initial ion concentration, and contact time were investigated and found to be 0.4g, pH 4, 308K, 10 mg/L, and 120 min, respectively. Mechanism study reveals the availability of amino groups in biopolymer, which act as active adsorption sites towards the arsenic anion. On evaluating isotherm models of Langmuir, Freundlich, Temkin, Elovich, Redlich-Peterson, and Dubbin-Radushkovich, it was found that the Langmuir isotherm model fitted better compared to other models having a maximum adsorption capacity of 28.99mg/g, a high regression coefficient value of 0.9988, least chi-square value of 0.1781 and validated by D-R isotherm also. The process was found to follow monolayer adsorption and pseudo-second-order kinetics. Thermodynamic parameters such as ∆S, ∆H, and ∆G indicated the spontaneous, endothermic, and physisorption nature of adsorption. Competing anions did not cause a significant reduction in the adsorption behavior of arsenic. Successful regeneration of the adsorbent implies its applicability to the removal of arsenic from real-life wastewater.

This study initially investigated sugar production through a Formose Reaction (FR) using methanol as a solvent and an aerosil (fumed silica) as a catalyst. The products observed in the reaction medium were 2,3-dihydroxypropanal (glyceraldehyde) and 1,2-ethanediol (ethylene glycol). The results showed that if the target of the reaction is to produce glyceraldehyde (GA) and ethylene glycol (EG), the aerosil is a better option as a catalyst in the FR. Finally, the Molecular Dynamic (MD) simulation of 2,3-dihydroxypropanal adsorption was investigated on montmorillonite (MMT) as a mineral adsorbent. MD simulation indicated that the adsorption of GA molecule at the MMT-water interface occurred due to the oxygen of the carbonyl group. The Radial Distribution Function (RDF) of the solvent around the main atoms of GA and the Root-Mean-Square Deviation (RMSD) were calculated from the MD simulation results using Gaussian and LAMMPS software. The RDF results showed a weak hydrogen bond between oxygen atoms of the hydroxyl group and solvent molecules. Moreover, the solvent molecules had no significant influence on the behavior of tetrahedral carbons of GA, indicating that the oxygen atom of the carbonyl group had a higher ability to form a hydrogen bond with water compared to the other atoms. The RMSD of carbonyl oxygen, carbonyl carbon, hydroxyl oxygen, and tetrahedral carbon increased during a simulation time of 20 ns, respectively. Evaluation of the mean distance of calcium atom at the surface of MMT and different atoms of GA showed that the GA molecule was chemically adsorbed on the surface of MMT by oxygen of carbonyl. The mean distances of C-tetrahedral, C-carbonyl, O-hydroxyl, and O-carbonyl in the GA structure from the surface of MMT (distance from calcium ions) were estimated to be 3.8, 3.2, 3.0, and 2.6 Å, respectively.

The chitosan was extracted from a whiteleg shrimp shell (Litopenaeus vannamei (by the deacetylation of chitin, which is carried out using 45% NaOH at 110 ºC for 6 h. The prepared chitosan was characterized by using the Fourier Transform InfraRed (FT-IR) spectroscopy, X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDXS), and ThermoGravimetric Analysis (TGA). The physicochemical property of this extracted polysaccharide, including the degree of deacetylation, apparent viscosity, molecular weight, Water Binding Capacity (WBC), and Fat Binding Capacity (FBC) from whiteleg shrimp shell was evaluated. The current study contrasted the characteristics of chitosan with the commercial type. Accordingly, to obtain the degree of deacetylation, the titration method and elemental analysis were considered, while the viscometric methods were used to achieve the molecular weight. The SPSS software was used for the analysis of the obtained data. Based on the comparison between the studied chitosan and commercial one, some behaviors were observed, including increased deacetylation and viscosity, decreased molecular weight, and higher water and fat binding capacities. The degree of deacetylation was determined as 86% for the titration method and 83% for elemental analysis. WBC and FBC of chitosan from shrimp were reported as 673.58 and 491.32, showing that all chitosan properties experienced a good improvement compared with the commercial type.

In this study, the Liquid-Liquid Extraction (LLE) method was used to demonstrate the extraction of Methylene Blue (MB) from aqueous solutions using 4.48 ´10(-1) mol/L Phenyl Propiolic acid benzene. The operating parameters like the changes brought by varying pH (liquefied solution pH), diluents, the concentration of extractant, and stripping reagents were evaluated with fixed reaction conditions. A maximum recovery of MB was obtained at pH 7±0.1. Similarly, the maximum stripping efficiency of MB was achieved by the use of 1 N H2SO4. The optimized parameter obtained for the recovery of MB from the LLE process was implemented in the Bbulk Liquid Membrane (BLM) technique. The separation and procurement of MB were performed in a single step is called the protraction process. The role of pH in the aqueous donor phase, the effect of phenyl propiolic acid concentration in the membrane phase, and the effect of stripping reagents concentration were evaluated in detail to understand the transport mechanism of MB from the aqueous phase to interface and interface to stripping solution.

The present study aimed to evaluate the physicochemical properties (refractive index, acid value, peroxide value, conjugated dienes, Fatty acid composition) and level of aflatoxins (AFB1, AFB2, AFG1, and AFG2) in the sesame oils (cold press) consumed in Iran. In total, 30 sesame oil samples were collected from factories (n=20; industrial) and traditional mills (n=10; non-industrial). No significant differences were observed between the industrial and non-industrial sesame oil samples in terms of the physicochemical properties and AF contamination and therefore, it is not possible to prefer the consumption of one of the oils (industrial or non-industrial) to another. According to the physicochemical examination, the mean peroxide value was 2.93±1.59 and 1.95±1.24 meq/kg, the acid value was 0.86±0.82 and 1.12±0.58 mg KOH/g, the refractive index was 1.4,706±0.0002 and 1.4,705±0.0001 at 28°C, and the conjugated diene value was 12.13±3.25 and 10.02±1.43 μmol/g in the industrial and non-industrial sesame oil, respectively. In addition, the fatty acid profile of the industrial and non-industrial sesame oil indicated high levels of unsaturated fatty acids (84.5% and 83.49%, respectively), with the main fatty acids determined to be oleic acid and linoleic acid. The fatty acid profile of the sesame oil samples indicated no adulteration with other vegetable oils. The mean contamination with AFB1, AFB2, and AFG1 in the non-industrial sesame oil was estimated at 0.06±0.26, 0.02±0.67, and 0.15±0.18 µg/kg, while the mean contamination with AFB1, AFB2, and AFG1 was 0.04±0.84, 0.03±0.61, and 0.17±0.16 µg/kg in the industrial sesame oil. Moreover, the AFB1 and AFs levels in all the sesame oil samples were significantly lower than the Iranian legislation limits (5 and 15 µg/kg, respectively) and the European Union (2 and 4 µg/kg, respectively). Risk assessment based on the margin of exposure revealed the risk of AFB1 and AFG1 exposure through industrial and non-industrial sesame oil consumption and AFB2 exposure through industrial sesame oil consumption.

In this work, the heat transfer coefficient in the pool boiling process was investigated for different alcoholic solutions. To exact evaluation, the bubble dynamic including bubble departure diameter, bubble departure frequency, and active nucleation sites’ density were studied. The results showed that with increasing isopropanol concentration (20 V.% - 80 V.%), bubble departure frequency and active nucleation sites increased while bubble departure diameter decreased. The bubble dynamic cannot be effective in any amount and must be optimized to reach an optimum heat transfer coefficient. Isopropanol concentration of 20 V.% was reported as an optimum state and lower decrease versus deionized water (11.892%). This result confirmed that the bubble departure diameter played a significant role in promoting the heat transfer coefficient. Finally, to predict the experimental data, a Genetic Algorithm (GA) based correlation (power-law function) was developed. The optimization procedure revealed that the GA model had a good agreement with the experimental data (R2=0.968, AAD= 0.0288). In addition, this approach was compared with conventional models (Palen, Stephan, Unal, Fujita, and Inoue).  The GA and the Stephan models presented the best and worst performance, respectively.

Recently, the pseudo lattice theory has been used to derive a simple linear correlation for the prediction of the surface tension of pure ionic liquids and their mixtures. That linear equation includes the parameters of coulomb interactions and the short-range interaction between the ions. In this work, a new correlation was derived for the solutions of ionic liquids in molecular solvents. The obtained correlation, predicts that the difference between the experimental surface tension and an approximated surface tension without including ion-solvent interaction, ( ) is a function of -5/3 order of molar volume.  can be calculated by using thermophysical experimental data. The linearity of the plots of  versus V-5/3 for mixtures of ionic liquids and solvents (alcohols and water) confirms the applicability of the pseudo lattice theory for these systems. The slope of the obtained lines, Bmix, is a measure of ion-solvent interaction and is independent of the temperature and mole fraction. Finally, an empirical linear relationship between Bmix and pure ionic liquid properties was extracted for each solvent. The equation of the last linear correlation is valuable for approximating and consequently, the surface tension of solutions at a varied range of temperatures and mole fractions.

Looking for the development of new food ingredients, the Box-Behnken design was employed to determine the effect of two different oleogels, elaborated with a celluloses mixture or with candelilla wax, as oil fraction, on the textural properties of emulsion-filled gels with egg white as emulsify/gelling agent, at different ionic strength conditions. Compression test parameters were determined on both samples (force, work, and modulus) to analyze the effect of the variables on texture. Emulsion-filled gels with candelilla wax oleogel resulted in firmer and more difficult to compress, as compared to cellulose oleogel, with a less hard and softer texture. The increase in protein concentration resulted in a stiffer texture, but when the oil fraction (oleogel proportion) increased, the emulsion-filled gel texture turned more squishable. No major effect was observed by the employed ionic strength conditions. The model predictions for textural parameters in both samples were closely correlated to the experimental results obtained. The use of different ingredients that can be employed as oil fractions with different textures that can be manipulated, distinct oleogel formulations -as the type of organogelator agent, a type of edible oil- allows the designing of textural and thermal properties of emulsion-filled gels, with great potential as fat replacers in processed foods.

Growing attention to the Geothermal Heat Pump (GHP) system highlights the necessity of using the technology in an optimized way. Since geographic and meteorological conditions have substantial effects on the efficiency of GHP, a technical and economic feasibility study on a regional scale was performed on residential buildings using R600a as a natural refrigerant. The investigation consists of numerical modeling and enhancement of Horizontal Geothermal Heat Pump Systems (HGHP) by a meta-heuristic algorithm, spatial cooling/heating design load calculation, and regional data exploration to attain a priority map based on economic factors of 96 geographical points in Iran as a case study. The modeling and optimization approach validation was investigated by comparing the computed results with those published in references. Particle Swarm Optimization (PSO) was used as an optimization tool due to its simplicity and accuracy. The effects of geographical factors, including heating & cooling load, cooling to heating load ratio, and different soil types on the objective function, and Total Yearly Cost (TYC) were presented in a table and investigated to have a better picture in a general exploration study. Finally, Iran's HGHP priority map was accurately presented in this study to help policymakers with decisions concerning technology subsidization. This map helps the investigators to have a better picture of the total affecting parameters on GHP system installation.

Bubble columns are frequently employed as multiphase reactors and gas-liquid contactors. In the bubble column, gas is dispersed into the liquid phase. The dispersion of gas into a liquid is the function of bubble size and its distribution. It also includes the complex process of coalescence and the break up of bubbles. The present research intends to examine the operating parameters' effect, including temperature on bubble characteristics in the ejector-induced downflow bubble column (i. d. 0.05 m X 1.6 m height) via Computational Fluid Dynamics (CFD) and experimental methods. Bubbles inside the column are analyzed and mean bubble diameters are obtained using a photographic technique. The effect of superficial gas velocity (4.25×10−3-9.68×10−3 m/s) and liquid velocity (8.5×10−2-14.11×10−2 m/s) on an average Sauter diameter is studied. The gas holdup variation with temperature (60-80 oC) is also examined. The temperature distribution at different axial locations (0.48-1.35 m) from the top of the column is observed using the CFD model. An empirical model for predicting the temperature, i.e., Tr (T/Tset), is proposed as a function of the Prandtl number, Weber number, Reynolds number, and Froude number.

The ion exchange process was employed to separate zirconium from hafnium in solution. To this end, four effective parameters, involving resin type, HCl concentration, Time, and initial zirconium concentration, were selected as the main variables. The sorption of zirconium and hafnium in the presence of six commercial macroporous anion exchangers of Dowex and Amberlite series and different HCl concentrations of 8-12 M were investigated. Furthermore, the distribution ratio, as a function of time in the range of 0.5-3 h and initial zirconium concentration of 500-3000 mg/L, was studied. The highest separation factor of 10.29 was obtained under equilibrium conditions in the presence of Amberlit CG-400II Ion Exchange Resin (IER) at a concentration of 9.5 M hydrochloric acid. Equilibrium isotherms of the system under optimized conditions were analyzed by Langmuir and Freundlich's adsorption models. The experimental data are well-described by the Langmuir equation for both zirconium and hafnium.

The movement state of contaminated oil in the pipeline is of great significance to the safe operation of oil-using equipment. The dynamic motion characteristics of the oil can be characterized by signals. However, the pressure signal of the oil is time-varying and complex; hence it is a typically non-stationary nonlinear signal. Therefore, the traditional linear analysis method used for the analysis of the oil signal is not suitable. For this reason, the Hilbert-Huang Transform (HHT) method is used to process and analyze the differential pressure signals of oils with different degrees of pollution, to obtain the characteristic frequencies of oil pressure signals, to explore the intrinsic connection of the characteristic frequencies and oils with different degrees of pollution, and to reveal the dynamic movement characteristics of oil in the pipeline. The results show that the characteristic frequencies corresponding to the five groups of oil samples with a pollution degree of 17/12,18/12,19/13,19/13,20/16 (ISO4406 standard) are 20.29 Hz, 10.22 Hz, 6.94 Hz, 17.01 Hz, and 6.81 Hz, respectively; Each Intrinsic Mode Function (IMF) component of the oil signal has obvious frequency modulation characteristics; As the pollution degree increases, the oil frequency of the IMF2-4 component mainly shifts toward the middle of the interval, and the oil frequency of the IMF5-7 component mainly shifts toward the direction of 5.00 Hz, 3.00 Hz, and 1.60 Hz respectively.

In this work, the densities of pure and binary mixtures of 1-pentanol or 1-decanol with 1,2-ethanediol or 1,2-propanediol or 1,3-butanediol or 2,3-butanediol were measured at atmospheric pressure and temperatures between 288.15K and 313.15K. For the considered system, two types of models were applied: black box and phenomenological. The black box model is represented by Artificial Neural Networks (ANNs) optimized with an improved version of Bacterial Foraging Optimization (iBFO). The phenomenological models are represented by Spencer-Danner and Li equations. In addition, in order to better fit the Spencer-Danner and Li equations to the obtained experimental data, the free parameters of these models were included in an iBFO algorithm. The average absolute error of the best ANN obtained was 2.82%, while the new forms of the Spencer-Danner and Li equations had an improvement from 26.31% and 26.51% respectively to 3.51% and 4.01% respectively. These results indicate the flexibility and efficiency of iBFO, which is able to provide good solutions for a variety of cases.

Bacterial Cellulose (BC) is commonly produced by a static batch culture, which is a time-consuming and low-yield process. Therefore, this study developed a new repeated static batch culture with optimal conditions to reduce production time, increase production value, and thus reduce BC production costs. First, by examining the volume of the surface ratio (depth) of the culture medium at 5 different levels and then the effect of cultivation time on the production efficiency of BC, at the desired depth of 1.6 cm, 5.6 g/L of BC per week was obtained. Then, for more production enhancement of BC, a new repeated static batch culture was developed at the obtained optimal conditions in the previous step. Then, by investigating the effect of the number of feed addition cycles in the repeated-batch culture, the maximum BC production of 13.06 g/L was obtained at the optimum cycle number 4 (7 days per cycle) with aeration. The highest amount of produced BC at the end of the 5th cycle was 41.15 g in a culture volume of 3.5 L at 6 cm depth. Aeration at the rate of 0.1vvm increased BC production in all cycles and decreased overall production time. The highest BC concentration was 13.27 g/L at the end of the third cycle, and the maximum production was 44.2 g at the end of the 4th cycle. A comparison of shear stress and Young's modulus of BC sheets produced in different cycles of the repeated-batch static culture with and without aeration showed that increasing the number of cycles as opposed to aeration makes a significant difference in the mechanical properties of the produced BC sheets.

Recently, microbial surface-active molecules called biosurfactants, have gained significant attention due to their structural diversity, biodegradability, low toxicity, and several environmental and industrial applications. However, despite their advantages, they are not widely used because of high production costs, which can be overcome by bioconversion of agro-industrial wastes as low-cost substrates. The current study aimed to overcome the challenges of biosurfactant production by bioconversion of soybean meal, as a low-cost renewable substrate, and to optimize the significant parameters. Rhamnolipid biosurfactant was produced by Pseudomonas aeruginosa (PTCC 1074) using soybean meal under solid-state fermentation and Response Surface Methodology (RSM) by Central Composite Design (CCD) was employed to optimize the significant parameters. The experimental value of biosurfactant production and Emulsification Index were 17.05 (g/kg dry substrate) and 54 % respectively under the optimal conditions (temperature 33 ºC, Initial substrate moisture 80%, and carbon-to-nitrogen ratio (C/N ratio) 54). Regression analysis with RSM resulted in quadratic models and the coefficient of determination (R2), adjusted R2, and predicted R2 were respectively calculated as 0.9767, 0.9557, and 0.9088, indicating that the model fitted the experimental data well.  An increase in temperature from 25 to 34°C led to a rise in rhamnolipid production, which implies the significant influence of temperature. The results demonstrated that  the production of biosurfactants increased with increasing the initial moisture content at high temperatures and also at low C/N ratios. The current study confirmed the considerable potential of soybean meal for biosurfactant production and also enhanced the production yield by optimizing the significant process parameters.

Excessive use of petroleum-based lubricants and their hazardous disposal has increased environmental pollution; hence the need for eco-friendly lubricants has been increased to meet the requirements of industry and automotive. Due to the oil crisis, the world’s attention has been diverted to producing bio-lubricants from non-edible sources. The use of non-edible sources can overcome the problems of toxicity, hazardous nature, and non-biodegradability. This study discusses the effect of various parameters on transesterification reaction to produce bio lubricant from Neem oil. The dried neem seeds were crushed, and the oil was extracted using the Soxhlet extraction method using n-hexane. The bio lube was produced by a double transesterification process using CaO as a catalyst. The effect of temperature, the molar ratio of ethylene glycol to oil, and catalyst wt% on yield bio lubricant was observed. The temperature varied from 110 to 140 °C, molar ratios of ethylene glycol to oil varied from 2:1 to 8:1, and the catalyst wt% was 0.8 to 1.6%, keeping the reaction time and other conditions constant. During the experimentation, it was observed that the yield was low at 110°C, but as the temperature increased, yield also increased, but no significant change in yield was observed beyond 130°C. The maximum yield observed at 130°C, and 140°C was 93.7% and 94.37%, respectively. Similarly, as the molar ratio increases, the yield of bio lube also increases, and the maximum conversion was 94.3% achieved at ethylene glycol to oil molar ratio of 8:1, but a molar ratio 6:1 may be considered optimum because there is no substantial increase in conversion after 8:1. Moreover, the profile was observed by varying the amount of catalyst and it is evident from the results, as the amount of catalyst increases as the conversion increases from 66% to 95%; however, at a catalyst ratio of 1.6 wt %, a yield was decreased slightly to 94.2. It has been observed that the temperature significantly impacts the production yield of Biolube.