Iranian Journal of Chemistry and Chemical Engineering
Volume:42 Issue: 8, Aug 2023

The application of bioactive natural oils in the food industry is limited due to their instability and poor solubility in hydrophilic media. This study aimed to investigate the effect of alginate microcapsules of linseed and black oil on microbial and sensorial properties of chocolate ganache during 28 days of storage. The results showed that both evaluated oils had considerable antibacterial effects against tested microorganisms (Salmonella Typhimurium, Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans) and gram-negative than gram-positive bacteria were more resistant to linseed oil. Therefore, Black seed oil showed higher antibacterial activity and both linseed and black seed oil microcapsules had lower antibacterial effects than their free form. The incorporation of encapsulated oils in chocolate ganache was not significantly different from the control samples. Although, the free form has shown higher antibacterial activity, due to the characteristics of protecting the bioactivity of oils from undesirable conditions, controlled release, and marketability of the product, loading the oils in an alginate bead is a suitable way for the application of black seed and linseed oil in food products.

In this paper, CoMoO4 Porous NanoSheets (PNSs) were successfully fabricated on a carbon cloth substrate by a low-temperature water bath method. Through morphological characterization and phase analysis, the synthesized product is CoMoO4 nanosheet, which has a porous structure with a diameter of about 400 nm and a thickness of about 100 nm. Through the electrochemical performance test, the synthesized product has good electrochemical performance. Under the condition of 1 A/g, the specific capacitance of CoMoO4 PNSs is 1800 F/g, and after 10000 cycles of charging and discharging, the capacity maintenance rate is 99.6%. CoMoO4 PNSs is a positive electrode, and activated carbon (AC) is a negative electrode. The device is assembled, and its theoretical voltage window reaches 1.6 V. After 8000 cycles of charging and discharging, the specific capacitance decreased from 121 F/g to 113 F/g, retaining 93.38% capacitance. In addition, we further studied the photocatalytic degradation of dyes on the synthetic materials. The degradation rates of Methyl orange (MO), Rhodamine B (RhB), and Congo Red (CR) dyes were 94.2%, 98.1%, and 96.4%, respectively. We further explored the cyclic stability of the material for RhB dye degradation. After 5 cycles of testing, it was found that the stability is very good, and can maintain 98.6%. The excellent electrochemical and photocatalytic properties of CoMoO4 PNSs are mainly attributed to the special porous sheet structure and CoMoO4 material. This work provides a new strategy and method for preparing excellent electrode materials and photocatalyst materials.

MicroPlastics (MPs) are plastic materials of micro-size dimension, often between the ranges of 1μm to 5mm. MPs are potential carriers that can adsorb metal ions in aquatic environments due to their specific surface areas. MPs and their associated contaminants can reach humans in many ways and are found in drinking water sources, foods, and beverages. The metal ions associated with MPs on their surfaces can desorb into the food materials and enter humans. The current research investigates the physicochemical parameters (pH, temperature, time, and type of plastic) affecting the desorption of metal ions from MPs into aqueous solutions using Inductively Coupled Plasma-Mass-Spectrometry (ICPMS). The MP surface characterization was studied using Fourier Transform Infrared (FT-IR) spectroscopy, X-Ray Diffraction (XRD), and The Brunauer-Emmett-Teller (BET) analysis. An experiment was conducted on three metal ions Lead, Cadmium, and Chromium on PET (polyethylene terephthalate), PP (polypropylene), PS (polystyrene), and PVC (polyvinyl chloride). In this work, PP showed the highest desorption efficiency, while PVC was the lowest one. Acidic pH 3.0 favored the desorption process and with an increase in temperature and time of contact with metal ions, the desorption efficiency also increased. The Scanning Electron Microscopic (SEM) characterization of MPs disclosed the presence of wrinkles and pits which encouraged both adsorption and desorption. The BET analysis revealed the role of high specific surface area (10.6±0.3 m2/g) and higher total pore volume (Vtotal) 1.58±0.09 cm3/g in significant adsorption and desorption of metal ions on PP.  The study findings provide a better perception of the desorbing efficiency of metal ions in the surrounding environment and the optimal conditions favoring this process.

Adsorption of phosgene on the surface of a graphene sheet was studied. The surface of this material was modified through a metamaterial approach using heteroatoms (N and B), the addition of hydrogen atom, and functionalized with four CHO groups at edges to survey the role of defects, Hydrogen Bonding (HB), and Intramolecular Hydrogen Bonding (IHB) interactions on adsorption. Generally, there is repulsion between the π-electron cloud of the graphene sheet and electrons of electronegative atoms on pollutants. However, the addition of hydrogen atoms to the surfaces of this material leads to the formation of attractive HB interactions with pollutants such as phosgene. Also, heteroatoms have helpful effects on the adsorption process. Therefore, the adsorption of phosgene on a modified graphene sheet is better than that of pristine graphene. Results of Molecular Dynamic (MD) simulations expose that van der Waals (vdW) and HB interactions have major contributions to the adsorption of phosgene on modified graphene.

In this study, the structural, spectroscopic, and electronic properties of N-(2,3,5,6-Tetrafluoropyridin-4-yl) formamide compound were investigated theoretically using the DFT/B3LYP method and 6-311++G(d,p) basis set. The obtained results were compared with geometric structure and 1H-NMR data known in the literature and were seen to be compatible. Characters of intermolecular interactions were explained by Hirshfeld surface analysis and molecular electrostatic potential map analysis. Electronic properties of the N-(2,3,5,6-Tetra fluoropyridin-4-yl) formamide compound were calculated considering frontier molecular orbital analysis. ADME study, conducted according to Lipinski's five criteria, revealed drug similarity properties of the N-(2,3,5,6-Tetrafluoropyridin-4-yl) formamide compound. In the last part of this study, the effect of nucleophilic substitution reactions on biochemical interactions between the perfluorinated compound and target protein was tested by molecular docking method using the Carbonic Anhydrase I (4WR7) enzyme.

We report here a new imine compound (Schiff base) with a hydrazide-hydrazone moiety, N'-(5-nitro-2-(piperidin-1-yl)benzylidene)benzohydrazide. The present work deals with synthesis, spectral and structural characterization, in silico drug-likeness, target identification and molecular docking studies of this compound. In this study, structural characterization was performed using complementary spectroscopic techniques, including X-ray, FT-IR, 1H-NMR, and UV-Vis. Surface properties and electronic studies were investigated using the method DFT/B3LYP. Drug-likeness, physicochemical and pharmacokinetic (ADME) properties, toxicity evaluation, and biological target identification were fulfilled using some bioinformatics and cheminformatics web tools. Draggability studies indicated two biological targets for our compound: microtubule-associated protein tau and protease, and docking studies were performed on tau fibrils (5V5C and 3OVL) and Mpro (6LU7) of SARS-CoV-2 accordingly.

In this research, Poly-Naphthalene Sulphonate (PNS) properties and working in concrete are enhanced to get the required workability and high strength of 10000psi. PNS usually does not work in high-strength concrete due to the presence of more cement content in its mix design. PNS dispersing effect in cement particles decreases as the cement content is increased. Therefore, its dispersion property and zeta potential are enhanced to make it compatible with high-strength concrete. Before modification, PNS is optimized in a mixed design of 10000psi concrete. When targeting dispersion, firstly PNS is modified by removing its oligomers which were creating a hindrance for cement particles. The required strength cannot be achieved while the required slump is achieved. In the other trial, sodium sulfate was added to concrete to increase dispersion by increasing sulfate ions in it, this sample did not work due to the presence of silica fume in the mix design. Similarly, many additives are added to increase dispersion like sulphonic acid with the defoaming agent, and by increasing gluconate dosage in the admixture solution. From the gluconate increment, get nearer to the required strength, which was not the exact required one. In the second phase, the hydration of cement is targeted by adding sodium lauryl ether sulfate to increase the viscosity of mixing water by which the active point of cement will increase but it gave the strength failure. Similarly, polytetrafluoroethylene was added which gave a better result but not the required strength. This additive is also tried with a gluconate-incremented sample to target both factors simultaneously. But the strength cannot be achieved and in the last by adding sulfuric acid to the mixing water rate of hydration of cement is slowed down by the water absorption principle and the required strength. The workability was achieved at a very cheap cost.

Today, the development of PET-based diagnostic radiopharmaceuticals is essential due to their accessibility by generators such as gallium-68 radioisotope. In this study, due to the distinctive properties of the bone-seeking agent of DOTA-ZOL, an effort is created to synthesize this valuable compound and use it in labeling with gallium-68. Further preclinical studies of  68Ga-DOTA-ZOL are performed, and therefore the human absorbed dose after injection of the labeled compound was estimated based on rat biodistribution data. DOTA-ZOL was synthesized and characterized by FT-IR, NMR, and MS analyses. A tin-based in-house 68Ge /68Ga generator was used for labeling studies. To get the simplest labeling condition of DOTA-ZOL, completely different experiments were performed by variable labeling parameters together with concentration, time, pH, and time. The radiochemical purity of the radiolabeled complex was examined using RTLC methodology by totally different solvent systems. The steadiness of the final complex was assessed in PBS and human serum. The biodistribution of the radiolabeled complex as well as 68GaCl3 was evaluated in normal rats up to 120 min post-injection. The human-absorbed dose of the complex was estimated using animal data 68Ga-DOTA-ZOL and was prepared with radiochemical purity of quite 97 at optimized conditions using synthesized DOTA-ZOL and an in-house generator. The complex was stable in both PBS (4 °C) and in human blood serum (37 °C). The biodistribution studies in normal rats showed a high accumulation of 68Ga-DOTA-ZOL injection with the most uptake at 30 min. The human absorbed dose estimation of the radiolabeled compound showed the highest absorbed dose is received by the bone tissue with the equivalent dose of 0.052 mGy/MBq. The results showed the attainable preparation of a new emerging bone-seeking agent of 68Ga- DOTA-ZOL using an in-house generator. Also, the radiolabeled compound is considered an approximately safe radiopharmaceutical in terms of radiation absorbed dose.

Synthesis of 2-amino-thiazoles from Nα-protected bromomethyl ketones obtained from Nα-protected diazomethyl ketones has been reported in this study.N-protected amino acids were converted to diazomethylketones using (Benzotriazol-1-yloxy) tris (dimethylamino) phosphonium hexafluorophosphate (BOP) as carboxylic acid activator and N-nitroso-N-methyl urea (NMU) as diazomethane source. Thus, prepared diazomethylketones were treated with aqueous HBr to get bromomethyl ketones in high yields. The 2-amino-thiazoles of protected-amino acids were prepared by sonicating the bromomethyl ketones with thiourea in acetone, using Hantzsch’s procedure. The products were obtained in good yields and were fully characterized. The purity of the synthesized compounds was analyzed by collecting the RP-HPLC data for two sets of compounds. Kirby Bauer well diffusion technique was employed to test the antibacterial activity of the compounds, Boc-Arg-thiazole, Cbz-Asp-thiazole, Cbz-Trp-thiazole, Fmoc-Phe-thiazole, and Fmoc-Trp-thiazole. The test leads to the promising activity with Streptomycin sulfate as standard and the compound Fmoc-Phe-thiazole was susceptible to Staphylococcus aureus.

An exclusive approach towards the synthesis of indoylquinoline alkaloids has been illustrated, the present article describes the synthesis, in Platelet-derived growth factor receptor and silico molecular docking studies of a new compound 3-indolylquinoline-2,4-diol 4. The synthesis of 4 is initiated by a new, efficient, and solvent-free via a thermal Claisen condensation. The structures of the compounds are established using both spectral and analytical data. An in-silico PASS, Swiss ADME-assisted docking approach is found to be suitable for deriving and synthesizing effective receptor tyrosine kinase agents. Claisen ester condensation reaction resulted in the discovery of inexpensive and user-friendly solvents. Structures of the newly synthesized compounds were characterized by FT-IR, 1H NMR, 13C NMR, and HRMS (FTMS+PESI) analyses.

The fabrication of potato starch-olive oil-graphene oxide bio-composite films was prepared via casting films-forming emulsion by adding Graphene Oxide (GO) to the Potato Starch-Olive Oil (PS/OO) matrix. The effects of olive oil and various amounts of graphene oxide on the performance of potato starch films were studied. Based on the results a combination of olive oil and GO was applied to diminish the Water Vapor Permeability (WVP) of the controlled films. Meantime, water solubility and moisture content decreased with olive oil incorporation and further decreased with increasing graphene oxide content. The addition of GO and olive oil into the films decreased the wettability of films. The mechanical strength was increased by the increment of GO and decreased with olive oil incorporation. The color properties and UV transmittance of the neat film were affected by adding olive oil and GO. XRD proved that the GO layers were intercalated in the PS/OO emulsion structure and FT-IR demonstrated that new interactions were formed between PS/OO/GO. Scanning Electron Microscope (SEM) demonstrated the dispensation of GO sheets inside the emulsion network. The surface roughness of films increased by adding GO and olive oil. Dynamic mechanical tests revealed that the incorporation of GO improves the thermal resistance, and storage modulus of the films, and diminished with olive oil incorporation.

In the present study, attempts are made to enhance the corrosion resistance in underground storage tanks. For this purpose glass fiber reinforced unsaturated polyester was used to coat the underground storage tank. The coating was applied by the hand layup technique. Multiple layers of glass fiber reinforced coating were applied, with the matrix composition of 97% polyester, 2% hardener, and 1% cobalt as an accelerator. Better corrosion resistance was observed when tested for the corrosion activity of the reinforcing steel with applied coating. It also provides better mechanical properties. For impact energy, the Izod test was performed. The mechanical properties and corrosion resistance were increased as increasing the fiber layers in the composite. This research is very helpful for future use as it provides a more cost-effective and better mechanical properties solution for the coating of the underground storage tank.

The inhibiting effect of Lavendula stoechas extract on the corrosion of Monel alloy 400 in 0.5 M sulfuric acid at different temperatures (298–328 K) was evaluated by mass loss measurements and electrochemical techniques, including Electrochemical Impedance Spectroscopy (EIS) and potentiodynamic polarization. The corroded surfaces of metal samples were examined using an atomic force microscope (AFM). Experimental results revealed that the inhibition efficiency increases with increasing inhibitor content and decreases with increasing temperature. The maximum inhibition efficiency was approximately 90.81%, and was reached in the presence of 0.25 g/L inhibitor at 298 K. The inhibitory action of Lavendula extract was realized via the adsorption of phytochemical constituents on the metal surface. The adsorption follows the Langmuir adsorption mechanism. Thermodynamic parameters suggested that the adsorption was spontaneous at different temperatures, supporting a mixed physisorption and chemisorption mechanism. Electrochemical impedance spectroscopy indicated that the inhibitor ameliorates the film formed at the metal/solution interface. Potentiodynamic polarization studies reveal that the inhibitor behaves as a mixed-type inhibitor,  with a predominantly anodic tendency. AFM studies confirmed the adsorption of Lavendula extract on the Monel alloy surface.

An accurate and dependable evaluation of the State of Charge (SOC) is required to maximize battery life and safety. The primary goals of this research are to identify dual-polarization parameters and estimate SOC. Dynamic identification of model parameters and estimation of battery SOC is achieved by co-estimating recursive Chicken Swarm Optimization (CSO) and Grey Wolf Optimization (GWO) algorithms from real-time current and voltage measurement data. A dual-polarization model's projected voltage is nearly the same as the actual voltage to better depict the dynamic properties of the battery and the identification process. Adaptive noise variance updating techniques applied to the extended improved SOC estimates. As a result, the proposed technique is validated using Dynamic Stress Test (DST) data and a Federal Urban Driving Schedule (FUDS). During FUDS testing, an estimated error of less than 2% and a root-mean-square error of less than 0.01085 are observed. We discovered that the approach can withstand erroneous beginning SOCs and other measurement noise covariance in the robustness study.

Lipids discharged into the yeast homogenate following the cell disruption process have a deleterious impact on the performance of chromatography columns during downstream processing. In this study, the removal of lipids from Pichia pastoris crude extract was investigated using various chemicals at varied concentrations. After treatment of the sample with 0.05 M borax and 1.5% PEI, a lipid reduction of about 52% and 79% was respectively obtained in the flocculated protein. The addition of PEG 6000 to the sample at a final concentration of 20% led to 57% lipid removal. A lipid reduction of 67%–70% was observed when protein precipitation was performed by 20%–40% ammonium sulfate. The efficiency of acetone and diethyl ether for lipid reduction was greater than that of isopropanol, and substantial lipid removal (95%–100%) was demonstrated after feedstock treatment with 0.5%–5% acetone and diethyl ether. After conducting detergent lipid dissolution experiments, it was revealed that non-ionic detergents (Triton X-100 and Tween 20) at a concentration of 0.1% were able to eliminate 100% of lipids in the feedstock. Overall, these findings suggest that such chemical treatment strategies may be considered to be used for pre-treating process streams and facilitating related research and applications in downstream processing.

A magnetic tragacanth gum-grafted poly(acrylic acid) hydrogel (TG-g-PAA/Fe3O4) was applied for the removal of Malachite Green (MG), basic yellow 28 (BY28) and rhodamine 6G (Rh6G) dyes form industrial simulated wastewater. The most important parameters (e.g., initial dye concentrations, adsorbent dosage, pH, and contact time) were optimized in all single, binary, and ternary systems. The adsorption processes were better fitted with the Langmuir model than the Freundlich model which revealed the linearity of the processes. Maximum adsorption capacities (Qm) for MG, BY28, and Rh6G in the ternary system were obtained as 626.5, 568.2, and 459.7 mg/g, respectively. Kinetic studies exhibited that the removal of all dyes in all systems was best fitted with the pseudo-second-order model, which proved the rate-limiting step might be the chemical adsorption. The hydrogel was regenerated by the desorption process after the loading process and reused several times. As a result, the removal efficiency of the adsorbent almost remains the same for the first four cycles.

In the present work, the sorption isotherms of tomato slices (TS) are obtained by the gravimetric method at different temperatures (50, 60, and 70 °C). After fitting the desorption curves, the Guggenheim-Anderson-de Boer (GAB) model is chosen as the most appropriate model for the experimental data of tomato slice desorption isotherm.  The isosteric heat of desorption is then determined by the Clausius-Clapeyron equation. Modeling of the convective drying kinetics is performed by experimental study of the effects of aerothermal conditions, such as temperature and hot air velocity. The drying characteristic curves are then fitted using MATLABR 2013 nonlinear regression- functions.  The parabolic model was found to be the most appropriate model for the experimental results of kinetic drying of tomato slices, with the highest R² correlation coefficient average value (0.9983) and the lowest RMSE average value (0.0119). The effective moisture diffusivity and the activation energy are tested by the second Fick's law. The values of effective moisture diffusivity ranged from 2.028 10-7 to 5.071 10–7 m²/s. The activation energy was calculated to be 42.140 kJ/mol.

The phase behavior of a new ternary aqueous two-phase system (ATPS) based on [1-Dodecyl-3-Methyl-Imidazolium][Dicyanamide] ionic liquid and an inorganic salt of KH2PO4 was investigated at two different salt concentrations and different temperatures of 288.15, 298.15, and 308.15 K, all under atmospheric pressure (0.1 MPa). This surface-active ionic liquid was chosen due to its similar properties to cationic surfactants and its widespread use in separation processes. The chemical structure of the synthesized ionic liquid was investigated using Fourier Transform InfraRed (FT-IR), Nuclear Magnetic Resonance (NMR), Diffuse Reflection Spectroscopy (DRS), residual chlorine test, and melting point test. The achieved experimental data correlated with the symmetrical local composition model of UNIQUAC-NRF with symmetric Pitzer−Debye−Hückel (PDH) theory. The results showed a minor influence of temperature on the separation process, and the salt ability in phase separation was increased at higher concentrations. A good agreement between correlated data and the experimental results was also found.

Worldwide economic growth and rising urban population, along with rapidly growing urbanization and industrialization, have led to the unrelenting production of municipal solid wastes (MSW). The concerns of rapid increase of energy demand consumption also concentrate the scientific attention on how to reuse the solid residues for generating bioenergy. The purpose of this article is to develop and introduce a novel MSW-driven plasma gasification system coupled with a carbon dioxide power cycle, organic Rankine cycle, and solid oxide fuel cell (SOFC), aimed at simultaneous waste management and power generation through an efficient and eco-friendly manner. The output of the MSW gasification process was used as a fuel of the SOFC system, and the sensible output heat of the SOFC is conducted to drive a combined power cycle; organic Rankine cycle and trans-critical carbon dioxide cycles. Aspen HYSYS/PLUS and MATLAB programming were used to model the developed structure. The SOFC and MSW plasma gasification process was validated and proved an appropriate approval. The output power generated by the integrated structure was calculated at 404.6 kW with 61.22%, 55.59%, and 21.53% for SOFC overall efficiency, gasification process energy efficiency, and overall thermal efficiency, correspondingly. The plasma energy ratio, Equivalence ratio, and steam-air mass ratio were defined to characterize the MSW plasma gasification process, and sensitivity analysis was applied to investigate the behavior of the system on different pressures, temperatures, air injection, and MSW mass flow rates. The sensitivity study revealed that the overall thermal and gasification process efficiencies increase up to 28.6% and 61%, respectively, when the MSW flow rate decreases from 400 to 250 kg/h.

One of the most common methods of drying is the use of heat. Therefore, high energy consumption has always been of concern in the drying process, and various methods have been tried to reduce high energy consumption. This research evaluated the performance of a thermal dryer with a closed air circulation system using porous metal-organic framework (MOF) nano sorbents. Dryer sections consisted of a crop drying chamber, connecting air pipes, air blowers, a chamber containing MOF nano sorbents, an electric air heater, and measurement and control systems. The performance of the dryer on the mint plant was compared at three temperature levels (40, 50, and 60 °C) and in two open and closed-air circulation methods. Finally, the energy consumption and efficiency were measured and evaluated for the dryer. The results showed that the closed air circulation system reduced energy consumption by 35% and therefore increased dryer efficiency, significantly affecting dryer efficiency and energy consumption. There was no obvious difference in the total color index between the two methods of use and without using nano sorbents. Antioxidant activity increased with increasing temperature. The study results indicated that a closed air circulation system significantly affects the dryer’s energy consumption and output. The highest output of the dryer was achieved at 50 °C when the dryer had been equipped with a closed air circulation system. No significant difference was evidenced in the total color index between the two applied methods when not using nano absorbents. The antioxidant activity was found to increase with the increase in temperature.

The study finds the mass transfer properties of Williamson fluid through permeable exponential stretched surfaces with slip boundary conditions. The two-dimensional flow model of Williamson fluid, along with boundary layer equations and mass transfer, are considered in the present paper. Mass transfer characteristics are studied for two instances, i.e., for Prescribed Exponential order Surface Concentration (PESC) and Prescribed Exponential order Mass Flux (PEMF). Similar variables are adapted to simplify the non-linear partial differential equations to ordinary differential equations, and finally, the resultant equations are resolved numerically. The physical characteristics of the flow model are evaluated graphically, and correlation with the literature reveals a satisfactory improvement in the current results.

The oil extraction from Bauhinia variegata seeds to produce biodiesel was performed using microwave-assisted extraction. About, 9 combinations of solvents were employed, and found that hexane-acetone (80:20 mL) gave a better yield, and the maximum bio-oil yield was found to be 29.03±0.61 % at the optimal condition of 9 min of processing time with a supply of 240 W and 12 mL/g of solvent volume. The presence of functional groups in the Bauhinia variegata seed oil was identified using FT-IR analysis and the fatty acid composition was analyzed using GC-FID. The results reveal a predominant fatty acid (C18:2) present in the group was linoleic (about 43.4%). From scanning electron microscopy analysis it was observed that the microwave treatment promoted rapid extraction of oil, as a structure of raw materials was ruptured. The physicochemical properties of the oil were determined as per ASTM D6751 and found that a free fatty acids value of less than one can be directly treated for the transesterification process. The results from this study suggest that MAE is an efficient and eco-friendly method to extract oil from Bauhinia variegata seeds in bio-diesel production.

This study aimed to compare the effect of different surface treatments on the bond strength of fiber posts to composite core material. Thirty light posts were divided into 5 groups. The control group did not receive surface treatment. The H2O2 group was etched with 10% hydrogen peroxide for 20 min, the HF group was etched with 9.5% Hydrofluoric acid for 60 sec, the APA group was air abraded with airborne particle abrasion, and the ER group was conditioned with erbium-doped yttrium aluminum garnet (Er: YAG) laser (250 mJ, 20 Hz, pulse duration of 100 μs for 1 min). This study aimed to investigate the post-surface preparation by chemical dissolution with materials such as oxygenated water, hydrofluoric acid, or mechanical stress using sandblasting and laser to determine whether these methods lead to increased bond strength. After composite core buildup, each sample was sectioned horizontally to create 1 mm-thick samples. The micro push-out bond strength was evaluated. Data were analyzed by ANOVA, Tukey’s post-hoc, and chi-square tests. The significance=0.05. The control and ER groups indicated the minimum and maximum bond strengths respectively. Interface adhesion was significantly improved in the ER and APA groups compared to the H2O2 group. APA and Er: YAG laser (250 mJ, 20 Hz, pulse duration of 100 μs for 1 min) were more efficacious than H2O2 in boosting the push-out bond strength of composite resin core material to DT-light fiber post.

Technological advances in electronic equipment and the variety-seeking behavior of people in using new equipment and devices have turned the issue of electronic waste (E-waste) into a major dilemma in the world. Electronic waste contains high levels of toxic metals such as lead and cadmium, base metals like aluminum and copper, precious metals such as silver, platinum, and palladium, and non-metallic parts consisting of resin, ceramic, plastic, and glass. There are different methods available to recover precious metals such as gold and platinum from electronic waste. However, the amino acid L-valine was used in this paper as a cheap and non-toxic leaching agent instead of cyanide. The grade of gold and platinum in the sample is 542 and 30 ppm, respectively, In addition, the parameters of L-valine concentration, temperature, pH, pulp solid percentage, and time were assessed by the Design of Experiments (DOE) method using the software. The experiments’ results demonstrated that the parameters of temperature, time, pH, pulp density, and L-valine concentration respectively have greater importance in the gold recovery process due to the lower P and higher F values. The mean percentage of gold recovery was obtained as 81.47% when validating the results under the proposed optimal conditions (L-Valine concentration: 173 g/t, pH: 11, time: 24 hours, temperature: 80 °C, pulp solid percentage: 19%, and constant stirrer speed: 400 rpm).

Naphtha in the presence of steam is cracked to produce ethylene, propylene, and 1,3-butadiene which are important feedstocks in the petrochemical industry. It is important to optimize industrial process conditions to maximize the yield of 16 desired products individually as well as a combination of those based on the market demand. The parameters influencing the naphtha cracking product yield are feed composition, Coil-Outlet Temperature (COT), coil-inlet pressure, residence time/feed flow rate, and Steam-to-Hydrocarbon Feed Ratio (SHFR). In this research, Box-Behnken response surface design has been used to evaluate the effects and interactions among three factors such as COT, SHFR, and feed flow rate on product yields by carrying out 15 experimental test runs. The SHFR, COT, and flow rates varied in the range from 0.38−0.5, 810−824 °C, and 14.8−17.2 tons per hour (tph), respectively. Models for three different naphtha feeds having different heavier hydrocarbon content (C8+) have been developed. Another model has been developed considering 27 experimental test runs with C8+ composition (3.74 wt.%, 6.81 wt.%, and 9.88 wt.%) as the fourth factor. These model results have been validated with Industrial process data on ethylene and propylene yields for ten case studies. The model-predicted yields match excellently well with that of industrial reactor yield. Response optimizer has been developed to optimize process conditions to maximize yields of ethylene, propylene separately, and also combined yield of ethylene+propylene+1,3-butadiene. It has been found that a higher COT has a favorable impact on Ethylene and 1,3-Butadiene yield. The Increased C8+ content results in a lower yield of Ethylene, Propylene, and 1,3-Butadiene. Increased SHFR and feed flow rate reduces the Ethylene yield. The optimized condition has been reported. The optimum was found at COT of 824°C, SHFR  of 0.4919 kg-steam/kg-naphtha, the flow of 14.8 tph, and C8+ contentin a feed of 3.74 wt.%.

This work investigates and compares the effectiveness of chemical advanced oxidation techniques to remediate real refinery wastewater generated from the Al-Samawa refinery plant which has not been treated before by using the present technologies. Real refinery wastewater underwent a batch photo-Fenton oxidation treatment (UV/H2O2/Fe2+) to reduce the oil content. The experiments were designed using a factorial experimental design containing the effects of 30-90 min irradiation time, 25–250 ppm hydrogen peroxide, and 2–8.5 pH. A statistical program was used to analyze the results. The optimum values of these variables were 90 min, 100 ppm H2O2, and pH 3. The effect of solution temperature on the removal efficiency was studied in the range of 20–400 °C. It was found that the temperature notably influences the treatment process, where the highest removal of the organic content of 95.15% was achieved at 30°C. Adsorption equilibrium investigation revealed that the Langmuir model was a more fitted model (R2 = 0.9999) for photo-Fenton elimination of oil content than other isotherm models. Consequently, a comparative study of the treatability of UV-photolysis, Fenton, and photo-Fenton processes has been conducted. The core findings of this comparison showed that the oil content removal by using the UV-photolysis process is (49.2%), the Fenton process (69.6%, while it shows that the photo-Fenton process is the most effective at getting rid of pollutants (92.75%). As observed the photo-Fenton methods are more effective than other studied methods to treat refinery wastewater.

Anaerobic digestion is the most commonly applied process for waste sludge treatment, which enables obtaining energy from the produced biogas. Biogas produced by anaerobic co-digestion of sludge with various additives can be used as an alternative fuel. Mathematical modeling of the Anaerobic Digestion (AD) process can greatly explain and facilitate the full-scale implementation of this process. In this work, a simulation of the process of co-digestion of waste sludge with fruit and vegetable waste was carried out numerically, with Anaerobic digestion model no. 1 model (ADM1) and experimentally. The data used to run the ADM1 model and its verification were obtained in a batch pilot reactor (25 L) and refer to Total Solids (TS), Volatile Solids (VS), Total Chemical Oxygen Demand (TCOD), Total Kjeldahl Nitrogen (TKN), total ammonia nitrogen, volatile fatty acids (VFA), pH value, conductivity, biogas volume produced, and its composition. The verification of the model was performed with experimental data about the biogas production, methane production, and pH value. Also, a sensitivity analysis was performed by variation of 53 parameters, to identify the most sensitive parameters of the ADM1 model for the co-digestion process. The best agreement between experimental and simulated data was obtained for methane production, while the most sensitive parameters are the biochemical hydrogen inhibition constant and the half-saturation constant.