A green and efficient synthesis of 2-thioxoquinazolinone derivatives in water using potassium thiocyanate

Green chemistry is one of the most important routes for the synthesis of heterocyclic compounds. In this regard, the synthesis of 2-thioxoquinazolinone derivatives was achieved by condensation of versatile materials including isatoic anhydride, amine and potassium thiocyanate in the green medium of water. This convenient and ef?cient method affords the desired products with good to excellent yields.     

APPLICATION OF GENETIC ALGORITHM FOR OPTIMIZATION OF SEPARATOR PRESSURES IN MULTISTAGE PRODUCTION UNITS

In this article, a genetic algorithm is used to optimize the separator pressures in a multistage crude oil and multistage gas condensate production unit with four and three separators respectively. This leads to the generation of more accurate results for the quality and quantity of oil remaining in the stock tank for both crude oil and gas condensate production units. Genetic-based optimized pressures for crude oil separators resulted in 1.8% and 2% enhancement in oil remaining in the stock tank for summer and winter respectively. API gravity of the stock tank oil was improved 2.4% in summer and 2.2% in winter. For the gas condensate production unit, optimized pressures can enhance by 8.6% and 8.1% the oil remaining in the stock tank for summer and winter respectively. The API gravity of stock tank liquid also increased by 2.6% for both summer and winter.     

Removal of Reactive Orange 12 from aqueous solutions by adsorption on tin sulfide nanoparticle loaded on activated carbon

In the present study, tin sulfide nanoparticle loaded on activated carbon simply was synthesized and characterized using different techniques such as SEM, XRD and UV-analysis. Then, this new efficient adsorbent was used for Reactive Orange 12 (RO-12) adsorption. To improve the efficiency of adsorption effect of variables viz. pH, mass of SnS-NP-AC, initial dye concentration, contact time and temperature were examined and optimized. The adsorption mechanism and rate of processes was investigated by analyzing time dependency data to various conventional kinetic models such as pseudo-first-order and second order, Elovich and intra-particle diffusion models. Among them it was found that adsorption followed the pseudo-second-order kinetic model with good agreement between the equilibrium experimental and expected adsorption data. High fitting with the Langmuir models shows heterogeneous surface and mono-layer nature adsorption of Reactive Orange 12 on the SnS-NP-AC. Thermodynamic parameters such as enthalpy (ΔH), entropy (ΔS), activation energy (E_a), of sticking probability (S^*) and Gibb's free energy changes (ΔG) were also calculated. It was seen that the proposed adsorbent has high tendency and adsorption capacity for RO-12 adsorption in a feasible, spontaneous and endothermic fashion.     

Design of an efficient uranyl ion optical sensor based on 1′-2,2′-(1,2-phenylene)bis(ethene-2,1-diyl)dinaphthalen-2-ol

A new optical uranyl (IV) selective sensor by incorporation of 1,1′-2,2′-(1,2-phenylene)bis(ethene-2,1-diyl)dinaphthalen-2-ol (PBED), dibutyl phthalate (DBP) and sodium tetraphenylborate (Na-TPB) in the plasticized poly vinyl chloride membrane matrices has been constructed. In the proposed optode, PBED functions as both ionophore and chromoionophore while DBP has synergistic effect on the complexation of uranyl ion (UO₂²⁺) by PBED. Following the optimization of influences of variables, the proposed sensor due to its high stability, reproducibility and relatively long lifetime has good selectivity and sensitivity for uranyl ion over a large number of alkali, alkaline earth, transition, and heavy metal ions. The response of the proposed optode is linear over the concentration range of 3.99 × 10^? 6 up to 8.06 × 10^? 5 mol L^? 1 of UO₂²⁺ within a detection limit of 9.99 × 10^? 7 mol L^? 1 and response time less than 10 min. The proposed optical sensor was applied successfully for the determination and evaluation of UO₂²⁺ ion content in water samples.     

Palladium,silver, and zinc oxide nanoparticles loaded on activated carbon as adsorbent for removal of bromophenol red from aqueous solution

The adsorption of bromophenol red (BPR) onto three adsorbents including palladium, silver and zinc oxide nanoparticles loaded on activated carbon (Pd-NP-AC, Ag-NP-AC and ZnO-NP-AC) in a batch system has been studied and the influence of various parameters has been optimized. The influence of time on removal of BPR on all adsorbent was investigated and experimental data were analyzed by four kinetic models including pseudo first and second-order, Elovich and the intraparticle diffusion equations. Following fitting the experimental data to these models, the respective parameters of each model such as rate constants, equilibrium adsorption capacities and correlation coefficients for each model were investigated and based on well known criterion their applicability was judged. It was seen that the adsorption of BPR onto all adsorbents sufficiently described by the pseudo second-order equation in addition to interparticle diffusion model. The adsorption of BPR on all adsorbent was investigated at various concentration of dye and the experimental equilibrium data were analyzed and fitted to the Langmuir, Freundlich, Tempkin, Dubinin, and Radushkevich equations. A single stage in batch process was efficient and suitable for all adsorbents using the Langmuir isotherm with maximum adsorption of 143 mg g^?1 for Pd-NP-AC, 250 mg g^?1 for Ag-NP-AC and 200 mg g^?1 for ZnO-NR-AC. Thermodynamic parameters such as ΔG°, ΔH°, and ΔS° for Pd-NP-AC adsorbent were calculated.     

SYNTHESIS AND CHARACTERIZATION OF CADMIUM SULFIDE NANOPARTICLE–LOADED ACTIVATED CARBON AS A NOVEL ADSORBENT FOR EFFICIENT REMOVAL OF REACTIVE ORANGE 12

The objective of this study was to evaluate the adsorption potential of cadmium sulfide nanoparticle–loaded activated carbon (CdSN-AC) for removal of reactive orange 12 (RO-12) dyestuffs from aqueous solutions. The characterization of CdSN-AC was performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM) techniques. The effects of experimental parameters such as initial solution pH, contact time, initial RO-12 concentration, amount of CdSN-AC, and temperature on the adsorption process were evaluated in detail. The kinetic studies indicated that the adsorption process was best described by the pseudo-second-order kinetics model. The experimental data were analyzed by the Langmuir, Freundlich, and Tempkin isotherm models, and the monolayer adsorption capacity of CdSN-AC was found to be 150.0 mg g^?1 by using the Langmuir isotherm model. The thermodynamic parameters indicated that the adsorption of RO-12 onto CdSN-AC was feasible, spontaneous, and endothermic in nature.     

Isolation of a novel mutant strain of Saccharomyces cerevisiae by an ethyl methane sulfonate-induced mutagenesis approach as a high producer of bioethanol

In order to obtain mutant strains showing higher bioethanol production than wild-type strains, a commercial Saccharomyces cerevisiae type was subjected to mutagenesis using ethyl methane sulfonate (EMS). After adding EMS to a shaken yeast suspension, the viability of yeast cells was assessed by diluted sample inoculation to solid yeast-extract peptone glucose (YEPG) medium at 15-min intervals. At 45 min, the viability of yeast cells was estimated to be about 40%. Mutagenized cells were recovered from YEPG broth after incubation at 30 degrees C for 18 h. After this period, EMS-treated yeast cells were grown on solid aerobic low-peptone (ALP) medium containing 2-12% (v/v) ethanol. All plates were incubated at 30 degrees C for 2-6 d in order to form colonies. The mutant strains that tolerated high concentrations of ethanol were selected for bioethanol production in microfuge tubes containing fermentation medium. Formation of bioethanol in small tubes was detected by the distillation-colorimetric method. In addition, trehalose content and invertase activity were determined in each mutant strain. Among many isolated mutant strains, there were six isolated colonies that grew on ALP medium supplemented with 10% (v/v) ethanol and one of them produced bioethanol 17.3% more than the wild type.     

Application of copper sulfide nanoparticles loaded activated carbon for simultaneous adsorption of ternary dyes: Response surface methodology

Copper sulfide nanoparticles were synthesized and loaded on activated carbon (CuS-NPs-AC) for ternary dye removal. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX) were used to characterize the synthesized materials. The performance of the materials was subsequently evaluated for simultaneous ultrasound assisted adsorption of Disulphine Blue (DB), Eosin Yellow (EY) and Safranin O (SO) dyes in ternary solution under different conditions that include variation in solution pH, initial concentrations of dyes, sonication time and adsorbent dosage. Response surface methodology (RSM) using central composite design (CCD) was employed to obtain the optimum experimental conditions. The maximum removal efficacies (88.39%, 68.49% and 55.69% for DB, EY and SO, respectively) were found at the optimum conditions: 3.63 min of sonication time, 0.02 g of CuS-NPs-AC, 7.76mg L^-1 of DB, 8.89mg L^-1 of EY, 9.87mg L^-1 of SO and pH 6.5. Very high adsorbent capacities of 198.12, 165.0, 139.58mg g^-1 for DB, EY and SO, respectively, were yielded from Langmuir isotherm as best fitted model. Kinetic study indicated that the pseudo-second-order kinetic model was well fitted to the experimental data of ternary adsorption process. The results of the study display very good adsorption efficiency of the synthesized adsorbent for dye removal with high adsorption capacity under optimum conditions.     

Preconcentration and separation of trace amount of copper (II) on N, N-bis(4-fluorobenzylidene)ethane-1,2-diamine loaded on Sepabeads SP70

A sensitive and simple method for the preconcentration of copper (II) ions has been reported. The method is based on the adsorption of copper ion N¹, N²-bis(4-fluorobenzylidene)ethane-1,2-diamine loaded on Sepabeads. The sorpted copper content was eluted by 8 ml of 4 M nitric acid in acetone. The influences of the analytical parameters including pH and sample volume were investigated. The interference effects of matrix ions on the retentions of the copper (II) ions were also examined. The recovery of understudy analyte was generally higher than 95%. The method has been successfully applied to the evaluation of copper contents in some real samples including water samples, vegetable samples and milk samples.     

Hydrophilic polymeric membrane supported on silver nanoparticle surface decorated polyester textile: Toward enhancement of water flux and dye removal

A novel mixed matrix nanofiltration membrane was constructed by coating a casting solution containing polyvinylidene fluoride(PVDF), polyethylene glycol(PEG) as hydrophilic agent, zeolitic like framework-67(ZIF-67), ethylenediamine as cross-linking agent on Ag-nanoparticle-decorated polyester textile(PT) support(PT/AgNPs/PVDF-PEG/ZIF-67). PT/Ag-NPs/PVDF-PEG/ZIF-67 morphology, crystalline structure, surface chemical composition and hydrophilicity of PT/Ag-NPs/PVDF-PEG/ZIF-67 were fully characterized by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR) and water contact angle technique, respectively. PT/Ag-NPs/PVDF-PEG/ZIF-67 was applied in cross module set-up for removal of contaminated water containing rose bengal(RB) dye. The effect of operational parameters such as dye concentration,solution pH and flow rate on performance of PT/Ag-NPs/PVDF-PEG/ZIF-67 were investigated and optimized by central composite design(CCD). Casting solution containing 0.5 wt.% ZIF-67 as optimum value showed the good wettability, high pure water flux(PWF; 35.8 L·m~(-2)·h~(-1)), flux recovery ratio(FRR;90%), dye removal efficiency(96.41%). The selectivity factor of 12.72 and 14.42 was found to be for RB in the presence of amido black and methylene blue as interferent dyes, respectively, which showed a good selective recognition ability for RB dye.