Sulfonic acid-functionalized silica: A remarkably efficient heterogeneous reusable catalyst for the one-pot multi-component synthesis of amidoalkyl naphthols

A novel, efficient and one-pot method for preparation of amidoalkyl naphthol derivatives is reported using sulfonic acid-functionalized silica as an effective heterogeneous catalyst under thermal solvent-free conditions. This method has the advantages of high yields, a cleaner reaction, simple methodology, easy work-up and greener conditions. The catalyst is easily prepared, stable (up to 300 C, reusable and efficient under the reaction conditions. Keywords: Amidoalkyl naphthols; Multicomponent synthesis; Solid acid; Sulfonic acid-functionalized silica; Heterogeneous recyclable catalys

MoO3-SiO2 as an efficient and reusable heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles

An efficient method for the preparation of 5-substituted 1H-tetrazole derivatives is reported using MoO3-SiO2 as an efficient heterogeneous catalyst. This method has the advantages of high yields, simple methodology and easy work-up. This catalyst could be recycledAn efficient method for the preparation of 5-substituted 1H-tetrazole derivatives is reported using MoO3-SiO2 as an efficient heterogeneous catalyst. This method has the advantages of high yields, simple methodology and easy work-up. This catalyst could be recycled very easily, which makes this methodology environmentally benign. Keywords: 5-substituted 1H-tetrazole, [2+3] cycloaddition, MoO3-SiO2, solid aci

Nano TiO2 as an efficient and reusable heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles

Nano TiO2 is an effective heterogeneous catalyst for the [2+3] cycloaddition of sodium azide with nitriles to afford 5-substituted 1H-tetrazoles in good yields. This method has the advantages of high yields, simple methodology and easy work-up. The catalyst is recovered and reused for several cycles with consistent activity. Keywords: 5-substituted 1H-tetrazole, [2+3] cycloaddition, nano TiO2, heterogeneous catalys

Solid silica-based sulfonic acid: A remarkably efficient heterogeneous reusable catalyst for the one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-triones

A novel, efficient and one-pot method for preparation of 2H-indazolo [2,1-b] phthalazine-trione derivatives is reported using solid silica-based sulfonic acid as an effective heterogeneous catalyst under thermal and solvent-free conditions. This method has the advantages of high yields, a cleaner reaction, simple methodology, easy work-up and greener conditions. The catalyst is easily prepared, stable (up to 300 C), reusable and efficient under the reaction conditions. Keywords: Dimedone, 2H-indazolo[2,1-b]phthalazine-trione, indazolophthalazine, solid silica-based sulfonic aci

Synthesis, characterization, and assessment of a CeO2@Nanoclay nanocomposite for enhanced oil recovery

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. In this paper, synthesis and characterization of a novel CeO2 /nanoclay nanocomposite (NC) and its effects on IFT reduction and wettability alteration is reported in the literature for the first time. The NC was characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), energy-dispersive X-ray spectroscopy (EDS), and EDS MAP. The surface morphology, crystalline phases, and functional groups of the novel NC were investigated. Nanofluids with different concentrations of 100, 250, 500, 1000, 1500, and 2000 ppm were prepared and used as dispersants in porous media. The stability, pH, conductivity, IFT, and wettability alternation characteristics of the prepared nanofluids were examined to find out the optimum concentration for the selected carbonate and sandstone reservoir rocks. Conductivity and zeta potential measurements showed that a nanofluid with concentration of 500 ppm can reduce the IFT from 35 mN/m to 17 mN/m (48.5% reduction) and alter the contact angle of the tested carbonate and sandstone reservoir rock samples from 139◦ to 53◦ (38% improvement in wettability alteration) and 123◦ to 90◦ (27% improvement in wettability alteration), respectively. A cubic fluorite structure was identified for CeO2 using the standard XRD data. FESEM revealed that the surface morphology of the NC has a layer sheet morphology of CeO2/SiO2 nanocomposite and the particle sizes are approximately 20 to 26 nm. TGA analysis results shows that the novel NC has a high stability at 90◦C which is a typical upper bound temperature in petroleum reservoirs. Zeta potential peaks at concentration of 500 ppm which is a sign of stabilty of the nanofluid. The results of this study can be used in design of optimum yet effective EOR schemes for both carbobate and sandstone petroleum reservoirs

Insight into nano-chemical enhanced oil recovery from carbonate reservoirs using environmentally friendly nanomaterials

The use of nanoparticles (NPs) in enhanced oil recovery (EOR) processes is very effective in reducing the interfacial tension (IFT) and surface tension (ST) and altering the wettability of reservoir rocks. The main purpose of this study was to use the newly synthesized nanocomposites (KCl / SiO2 / Xanthan NCs) in EOR applications. Several analytical techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM) were applied to confirm the validity of the synthesized NCs. From the synthesized NCs, nanofluids were prepared at different concentrations of 100-2000 ppm and characterized using electrical conductivity, IFT, and ST measurements. From the obtained results, it can be observed that 1000 ppm is the optimal concentration of the synthesized NCs that had the best performance in EOR applications. The nanofluid with 1000 ppm KCl / SiO2 / Xanthan NCs enabled reducing the IFT and ST from 33 and 70 to 29 and 40 mN/m, respectively. However, the contact angle was highly decreased under the influence of the same nanofluid to 41° and the oil recovery improved by an extra 17.05 % OOIP. To sum up, KCl / SiO2 / Xanthan NCs proved highly effective in altering the wettability of rocks from oil-wet to water-wet and increasing the cumulative oil production

Application of a novel green nano polymer for chemical EOR purposes in sandstone reservoirs: Synergetic effects of different fluid/fluid and rock/fluid interacting mechanisms

In this research, a novel natural-based polymer, the Aloe Vera biopolymer, is used to improve the mobility of the injected water. Unlike most synthetic chemical polymers used for chemical-enhanced oil recovery, the Aloe Vera biopolymer is environmentally friendly, thermally stable in reservoir conditions, and compatible with reservoir rock and fluids. In addition, the efficiency of the Aloe Vera biopolymer was investigated in the presence of a new synthetic nanocomposite composed of KCl-SiO2-xanthan. This chemically enhanced oil recovery method was applied on a sandstone reservoir in Southwest Iran with crude oil with an API gravity of 22°. The Aloe Vera biopolymer’s physicochemical characteristics were initially examined using different analytical instruments. The results showed that the Aloe Vera biopolymer is thermally stable under reservoir conditions. In addition, no precipitation occurred with the formation brine at the salinity of 80,000 ppm. The experimental results showed that adding ethanol with a 10% volume percentage reduced interfacial tension to 15.3 mN/m and contact angle to 108°, which was 52.33 and 55.56% of these values, respectively. On the other hand, adding nanocomposite lowered interfacial tension and contact angle values to 4 mN/m and 48°, corresponding to reducing these values by 87.53 and 71.42%, respectively. The rheology results showed that the solutions prepared by Aloe Vera biopolymer, ethanol, and nanocomposite were Newtonian and fitted to the Herschel-Bulkley model. Finally, core flooding results showed that the application of a solution prepared by Aloe Vera biopolymer, ethanol, and nanocomposite was effective in increasing the oil recovery factor, where the maximum oil recovery factor of 73.35% was achieved, which could be attributed to the IFT reduction, wettability alteration, and mobility improvement mechanisms

Applying artificial neural network and response surface method to forecast the rheological behavior of hybrid nano‐antifreeze containing graphene oxide and copper oxide nanomaterials

In this study, the efficacy of loading graphene oxide and copper oxide nanoparticles into ethylene glycol-water on viscosity was assessed by applying two numerical techniques. The first technique employed the response surface methodology based on the design of experiments, while in the second technique, artificial intelligence algorithms were implemented to estimate the GO-CuO/water-EG hybrid nanofluid viscosity. The nanofluid sample’s behavior at 0.1, 0.2, and 0.4 vol.% is in agreement with the Newtonian behavior of the base fluid, but loading more nanoparticles conforms with the behavior of the fluid with non-Newtonian classification. Considering the possibility of non-Newtonian behavior of nanofluid temperature, shear rate and volume fraction were effective on the target variable and were defined in the implementation of both techniques. Considering two constraints (i.e., the maximum R-square value and the minimum mean square error), the best neural network and suitable polynomial were selected. Finally, a comparison was made between the two techniques to evaluate their potential in viscosity estimation. Statistical considerations proved that the R-squared for ANN and RSM techniques could reach 0.995 and 0.944, respectively, which is an indication of the superiority of the ANN technique to the RSM one.https://www.mdpi.com/journal/sustainabilitydm2022Mechanical and Aeronautical Engineerin

Simulation of nanofluid flow in a micro-heat sink with corrugated walls considering the Effect of Nanoparticle Diameter on Heat Sink Efficiency

In this numerical work, the cooling performance of water–Al2O3 nanofluid (NF) in a novel microchannel heat sink with wavy walls (WMH-S) is investigated. The focus of this article is on the effect of NP diameter on the cooling efficiency of the heat sink. The heat sink has four inlets and four outlets, and it receives a constant heat flux from the bottom. CATIA and CAMSOL software were used to design the model and simulate the NF flow and heat transfer, respectively. The effects of the Reynolds number (Re) and volume percentage of nanoparticles (Fi) on the outcomes are investigated. One of the most significant results of this work was the reduction in the maximum and average temperatures of the H-S by increasing both the Re and Fi. In addition, the lowest Tmax and pumping power belong to the state of low NP diameter and higher Fi. The addition of nanoparticles reduces the heat sink maximum temperature by 3.8 and 2.5% at the Reynolds numbers of 300 and 1800, respectively. Furthermore, the highest figure of merit (FOM) was approximately 1.25, which occurred at Re 1800 and Fi 5%. Eventually, it was revealed that the best performance of the WMH-S was observed in the case of Re 807.87, volume percentage of 0.0437%, and NP diameter of 20 nm.Taif University, Taif, Saudi Arabiahttp://www.frontiersin.org/Energy_Researcham2022Mechanical and Aeronautical Engineerin