Biodesulfurization of fossil fuels is a promising method for treating the sour oil due to its environmental friendliness and ability to get rid of the recalcitrant organosulfur compounds. In this ...study, many types of microorganisms such as Ralstonia eutropha, Rhodococcus erythropolis, Acidithiobacillus ferrooxidans, and Acidithiobacillus thiooxidans applied on a sour heavy crude oil (sulfur content was 4.4%). Also, a colony isolated from the crude oil and oil concentrate was examined by supplying it with PTCC 106. The various official and famous mediums were significantly evaluated such as (PTCC 2, PTCC 105, PTCC 106 (9K), PTCC 116, PTCC 123, PTCC 132), sulfur-free MG-medium, basal salts medium, and mineral salts. It was found that Rhodococcus erythropolis and Acidithiobacillus ferrooxidans from microorganisms and SFM and the medium PTCC 105 were selected as the higher desulfurization efficiencies of crude oil equaling 47 and 19.74% respectively. The bioreactions depend on the treated fluid, targeting sulfur compounds as these represent the environmental status (amounts and types of nutrients), and the type of biotreaters whether microorganism are septic, semiseptic, or aseptic. The optimum operation conditions have been designed by using Definitive method such as mixing speed, temperature, surfactant dose, OWR, acidity. The optimum efficiencies obtained here are better than the previous efforts even though those gained by bioengineering. Biodesalination was a simultaneous process with the BDS.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The influence of dissolution of hydrocarbons extracted by different solvents from oily sludge on petroleum products was studied by ASTM quality control tests. The results indicated that utilizing a ...shaker provided a higher extraction percentage than a mixer. Besides, chloroform held the highest extraction of total petroleum hydrocarbons (TPH). The extracted TPH by solvents had almost an undesired effect on the color quality index. After dissolving the extracted TPH in the initial gas oil, no significant change was observed in the density of gas oil. The influence of the dissolution of extracted TPH by solvents was greater than their effect on the specific gravity of the initial gas oil. It can be concluded that mixing the extracted petroleum hydrocarbons was suitable for re‐addition to gas oil.
The influence of dissolution of hydrocarbons extracted from oily sludge by using four solvents and their combinations on petroleum products was investigated by ASTM quality control tests. The total petroleum hydrocarbons extracted by solvents were not suitable for dissolving in petrol, whereas they were proper for mixing with gas oil. The shaker method provided the highest hydrocarbon extraction.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Rhamnolipids are a group of the extracellular microbial surface-active molecules produced by certain Pseudomonas species with various environmental and industrial applications. The goal of the ...present research was to identify and optimize key process parameters for Pseudomonas aeruginosa PTCC 1074s synthesis of rhamnolipids utilizing soybean meal in solid state fermentation. A fractional factorial design was used to screen the key nutritional and environmental parameters to achieve the high rhamnolipid production. Response surface methodology was used to optimize the levels of four significant factors.
The characterization of biosurfactant by TLC, FT-IR and H-NMR showed the rhamnolipids presence. In the optimum conditions (temperature 34.5 °C, humidity 80%, inoculum size 1.4 mL, and glycerol 5%), the experimental value of rhamnolipid production was 19.68 g/kg dry substrate. The obtained rhamnolipid biosurfactant decreased water's surface tension from 71.8 ± 0.4 to 32.2 ± 0.2 mN/m with a critical micelle concentration of nearly 70 mg/L. Additionally, analysis of the emulsification activity revealed that the generated biosurfactant was stable throughout a broad pH, temperature, and NaCl concentration range.
The current study confirmed the considerable potential of agro-industrial residues in the production of rhamnolipid and enhanced the production yield by screening and optimizing the significant process parameters.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this research, silver nanoparticles (SNPs) were synthesized through bio-reduction of silver ions using the Spirogyra varians. The procedure used is simple and sustainable making it suitable for ...economic production of SNPs. The structure and morphology of SNPs were characterized by UV–visible spectroscopy, X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and Fourier Transform Infra-Red (FTIR). These nanoparticles indicated an absorption peak at 430nm in the UV–visible spectrum. The crystallite average size was estimated about 17.6nm and SEM image confirmed synthesis of relatively uniform nanoparticles. The antibacterial effect of SNPs was also tested on several micro-organisms by measuring the inhibition zone, MIC and MBC. The results confirmed that SNPs can act as a powerful antibacterial agent against various pathogenic bacteria.
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GEOZS, IJS, NUK, OILJ, SBJE, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the current study, the leaching conditions of chalcopyrite/pyrite concentrate were optimized by sulfuric acid and hydrogen peroxide using response surface methodology (RSM). The optimal leaching ...conditions were found to be a sulfuric acid concentration of 150 g/L, a hydrogen peroxide volume of 350 mL, a temperature of 80 °C, a leaching time of 8h and a solid-liquid ratio of 0.52 g/mL. After analysis of variance (ANOVA), the sulfuric acid concentration and temperature were the most significant process variables for the leaching concentrations of both copper and iron. Under the optimum conditions, the recovery of copper and iron was 81.83% and 67.57%, respectively.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Abstract
Biodesulfurization of fossil fuels is a promising method for treating the high sulfur content of crude oils and their derivatives in the future. This method is environmentally friendly and ...can desulfurize recalcitrant organosulfur compounds. Bioreactions depend on the treated fluid, targeted sulfur compounds, and the biotreaters applied. Various analytical methods support this treatment, including measurement of total sulfur and speciation of organosulfur compounds (HCS). Monitoring of intermediates, end products, biomass growth, and identification using methods such as genes, DNA, and hydrocarbons is also possible. Additionally, testing the occurrence of desired and undesired products is important. This history review summarizes these methods.
Lactic acid fermentation is an end product inhibited reaction. In situ separation of lactic acid from fermentation broth using ion exchange resins was investigated and compared with conventional ...fermentation system. Amberlite resin (IRA-400, Cl
−
) was used to separate lactic acid from fermentation broth and pH was controlled online with an automatic pH controller. The effect of process variables on lactic acid production by
Lactobacillus casei
in whey permeate was studied. The maximum productivity was obtained at pH = 6.1,
T
= 37 °C and impeller speed = 200 rpm. The maximum concentration of lactic acid at optimum condition was found to be 37.4 g/L after 38 h of fermentation using in situ separation system. The productivity of in situ separation system was five times increased in comparison with conventional system.
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CEKLJ, DOBA, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Biodesulfurization (BDS) of fossil fuels is a promising method for treating the high content of sulfur in crude oils and their derivatives in the future, attributed to its environmental-friendly ...nature and the technical efficient ability to desulfurize the organosulfur compounds recalcitrant on other techniques. It was found that the bioreaction rate depends on the treated fluid, targeting sulfur compounds, and the microorganism applied. Also, many studies investigated the operation conditions, specificity, and biocatalysts modification to develop BDS efficiency. Furthermore, mathematical kinetics models were formulated to represent the process. In this review, the previous studies are analyzed and discussed. This review article is characterized by a clear picture of all BDS's experimental, industrial, procedural, theoretical, and hypothetical points.
In this study, mechanical behavior of multilayer corrugated core laminated composite sandwich panel subjected to quasi-static three-point bending is investigated experimentally as well as ...numerically. Parameters such as contact force, energy absorption and specific absorbed energy (unit mass energy) for different geometries of corrugated core (rectangular, trapezoidal and triangular) are studied during loading process and failure. Composite plates and corrugated cores have been manually made using ML506 epoxy resin with 15% hardener and 45% volumetric woven glass fibers. Experimental results show that multilayer sandwich composite panels not only strengthen the structure in the quasi-static three-point bending process, but also make the absorbed energy to grow significantly by increasing the contact force and displacement up to the complete failure. The main mechanisms of damage and failure of sandwich panel specimens during load bearing process are matrix cracking, fiber breakage, delamination, local indentation, global bending, crushing and buckling of cell walls and face sheet and core de-bonding. Rectangular geometry of corrugated core, in terms of energy absorption and specific energy exhibits better results in comparison to other shapes. Numerical simulation using ABAQUS FEA package led to results, which are in good agreement with experimental ones and make it possible to use simulation instead of costly tests for analysis and design.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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