In this research work, a new magnetic Schiff's base-chitosan-Benzil/zinc oxide/Fe3O4 nanocomposite (Cs-Bz/ZnO/Fe3O4) was developed to be a promising and recoverable adsorbent for Remazol Brilliant ...Blue R dye (RBBR) removal from the aquatic environment. Parametric optimization by Box–Behnken design was made to optimize the synthesis condition (loading ZnO nanoparticles into polymeric matrix of Cs) in addition to adsorption operation parameters (adsorbent dose, solution pH, temperature, and contact time). The obtained results show that the fast RBBR removal (98.8%) can be achieved by loading 25% ZnO nanoparticles into polymeric matrix of Cs (Cs-Bz/ZnO-25/Fe3O4), and at optimum adsorption operation parameters (adsorbent dosage of 0.04 g, solution of pH 4, temperature of 60 °C, and contact time of 10 min). At these optimum conditions, the maximum adsorption capacity was found to be 620.5 mg/g. The best isotherm and kinetic models were Freundlich model and pseudo-second-order kinetic model, respectively. The probable RBBR dye adsorption mechanism can be assigned to various types of physicochemical interactions (i.e; electrostatic, n-π, π-π interactions) in addition to hydrogen bonding and Yoshida H-bonding. The output of this research confirms that Cs-Bz/ZnO-25/Fe3O4 is a superior, recoverable, and environment friendly biohybrid nanocomposite adsorbent. The remarkable output of this research can open a window for other possible significant applications such as tenement of real waste water, removal of heavy metal ions, and reduction of chemical oxygen demand.
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•A magnetic Schiff's base-chitosan-Benzil/ZnO/Fe3O4 (Cs-Bz/ZnO/Fe3O4) was synthesized.•The synthesis condition of Cs-Bz/ZnO/Fe3O4) was optimized by Box–Behnken design.•The adsorptive removal of RBBR dye by Cs-Bz/ZnO/Fe3O4 was optimized by Box–Behnken design.•The adsorption capacity for RBBR was 620.5 mg/g.
•Investigated suitability of rotating packed beds for heat transfer applications.•Used response surface method to generate regression equation for outcomes.•Achieved cooling effectiveness of up to ...0.59 and Merkel number up to 1.88.•Studied feasibility of rotating packed bed as an alternative to cooling tower.
Cooling towers play a crucial role in various industries to dissipate the heat of circulating water. This process involves the direct contact of atmospheric air and hot water from the condenser within a porous packed bed. The cooling towers suffers from their large size which results in escalating construction and maintenance expenses. In the present work, a rotating packed bed has been investigated experimentally for its evaporative heat transfer performance and is proposed as an alternative to cooling towers. In the chemical and processing sectors, rotating packed beds are being explored as a potential alternative to conventional distillation towers due to their process intensification capabilities. The principal reason behind this adaptation is the enhanced mass transfer rates achievable by rotating packed beds in a compact size. The aim of this study is to lay the foundation for rotating packed beds to achieve similar process intensification in various heat transfer applications. For this purpose, the parameters that describe the performance of a cooling tower such as air pressure drop, cooling range, heat rejection rate from water, cooling effectiveness, and Merkel number were selected to assess the performance of the rotating packed bed. The effect of various factors such as mass flow rate of air, mass flow rate of water, water inlet temperature, and rotational speed on the performance parameters was observed. Response surface methodology was used for the design of experiments, development of the regression equations, and optimization of the performance parameters of rotating packed bed. The cooling effectiveness value of up to 0.59 and the Merkel number of up to 1.88 were achieved in the rotating packed bed.
•DES is a new generation of environment-friendly solvent with unique physicochemical properties.•DES is an efficient and convenient solvent for polysaccharides extraction from bladder-wrack.•Response ...surface methodology (RSM) was used for optimizing the extraction conditions.•Antioxidant and anticancer activity of polysaccharides from bladder-wrack in vitro was evaluated.
Based on natural deep eutectic solvents (DESs), microwave-assisted green extraction was applied for production of polysaccharides from bladder-wrack (Fucus vesiculosus). In this study, nine different combinations of deep eutectic solvents were evaluated for extraction of polysaccharides from bladder-wrack, and the results showed that DES system composed of choline chloride and 1,4-butanediol with molar ratio of 1:5 possessed the optimal extraction efficiency for polysaccharides. A three-level and four-variable Box-Behnken design (BBD), a specific design of response surface methodology (RSM), was used to determine the optimum extraction conditions for the maximum yields of polysaccharides from bladder-wrack by using DESs. The maximum yields of polysaccharides attained 116.33 mg/g within DES water content of 32%, extraction time of 35 min, extraction temperature of 168 °C and solid–liquid ratio of 39 mg/mL. After partial separation and purification of the polysaccharides extracted by DESs, antioxidant activity and anticancer activity in vitro were evaluated. The results revealed that polysaccharides extracted from bladder-wrack exhibited excellent antioxidant activities in vitro including DPPH and ABTS radical-scavenging activity. For human cervical cancer HeLa cells, the polysaccharides possessed a strong inhibition effect on the growth rate. So these results indicate that deep eutectic solvent, as an environmentally-friendly solvent, can be applied to extract polysaccharides from multifarious plant materials.
In this study, response surface methodology (RSM)–artificial neural network (ANN) approach was used to optimise/model disperse dye removal by adsorption using water treatment residuals (WTR). RSM was ...first applied to evaluate the process using three controllable operating parameters, namely WTR dose, initial pH (pHinitial) and dye concentration, and optimal conditions for colour removal were determined. In the second step, the experimental results of the design data of RSM were used to train the neural network along with a non-controllable parameter, the final pH (pHfinal). The trained neural networks were used for predicting the colour removal. A colour removal of 52.6 ± 2.0% obtained experimentally at optimised conditions (pHinitial 3.0, adsorbent dose 30 g/L and dye concentration 75 mg/L) was comparable to 52.0% and 52.2% predicted by RSM and RSM-ANN, respectively. This study thus shows that optimising/predicting the colour removal process using the RSM–ANN approach is possible, and it also indicates that adsorption onto WTR could be used as a primary treatment for removal of colour from dye wastewater.
•Water treatment residual (WTR) is a potential sorbent for colour removal.•Up to 52% colour removal can be obtained with WTR at optimum conditions.•Optimisation with RSM-ANN approach is possible.
In the present work, (ZnNi) coatings were pulsed-plated over a mild-steel (MS) substrate from an acidic chloride electrolyte. The coating's morphology, topography, chemical composition, and phase ...composition were evaluated by scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) techniques. Electrochemical methods such as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests were conducted to assess the coating's corrosion behavior in brine solution. With the help of a Box-Behnken design, the coating's electrochemical performance was assessed under the effect of three electroplating variables: bath temperature (A), plating current density (B), and stirring rate (C). The statistical model found the optimum electroplating variables to be A = 45 °C, B = 100 mA.cm−2, and C = 0 rpm, yielding corrosion rate and polarization resistance values of 0.61 (± 0.10 mm.year−1) and 445.52 (±20.23 Ω), respectively.
•Optimization of electrodeposition parameters by response surface methodologies.•ZnNi nanocrystalline coatings are deposited over mild steel.•Statistical model for processing reproducible high-corrosion resistant coatings.•ZnNi coatings for corrosion protection of steel components in coastal environments.
Environmental pollution is increasing worldwide due to population and industrialization. Among the various forms of pollution, water pollution poses a significant challenge in contemporary times. In ...this study, we synthesized CuO-decorated montmorillonite K30 (MK30) nanosheets via a simple ultrasonication technique. The structural, morphological, compositional, and optical properties of the synthesized nanocomposites were evaluated using advanced instrumentation techniques. The morphology of CuO was cubic and cubic CuO evenly designed on the MK30, which was proved by Field Emission Scanning Electron Microscopy (FESEM). The adsorption photocatalytic activity of the synthesized cubic CuO/MK30 composites was examined through the degradation of MB under visible light irradiation. The apparent reaction rate constant of 20% CuO/MK30 was 12.5 folds higher than that of CuO. These conditions included a catalyst dosage ranging from 5 to 15 mg, a pH level ranging from to 3-11, and a pollutant concentration ranging from 5 to 20 mg/L. The optimal conditions for MB dye removal were determined using response surface methodology (RSM). A scavenger study of the composite was conducted and verified that •O2- and •OH radicals play an important role in the degradation process. This investigation addressed the process of adsorption and potential removal pathways, with a particular emphasis on the role of functional groups. The environmentally friendly CuO/MK30 nanocomposites exhibited potential as photocatalysts for efficiently absorbing and degrading MB dye and TC drug pollutants. They represent promising candidates for the treatment of industrial wastewater, aiming to mitigate the environmental threats posed by organic pollutants.
•Successful synthesis of cube-shaped CuO-decorated MK30 nanocomposite using ultrasonication•Examination of photocatalytic removal activity for MB dye and TC drug.•Significant enhancement in reaction rate with 20% CuO/MK30 nanocomposite and it was 12.5 folds higher than CuO.•Determination of optimal conditions for MB dye removal using response surface methodology•The paper discussed the process of adsorption and potential pathways of photodegradation, focusing on the involvement of functional groups.
•The magnetic chitosan/activated carbon bio-nanocomposite was modified with UiO-66 MOFs.•Ultrasound-assisted simultaneous adsorption removal of cobalt (II) ions, malachite green dye, and imidacloprid ...pesticide from aqueous solution.•The maximum adsorption capacity of adsorbent in a ternary model were, 44.5, 62.1, and 25.2 mg g−1 for Co (II), MG, and IMI respectively.•The adsorption process parameters were optimized by response surface methodology based on central composite design (RSM-CCD).•Adsorption results have been analyzed by isotherm, kinetic, and thermodynamic studies.
In this study, the modification of magnetic chitosan/activated carbon bio-nanocomposite (MCS/AC) with UiO-66 MOFs (MCS/AC@UiO-66) was carried out, and the obtained bio-nanocomposite was applied as an efficient adsorbent for the ultrasound-assisted simultaneous adsorption removal of cobalt (II) ions (Co (II)), malachite green (MG) dye, and imidacloprid (IMI) pesticide from aqueous solution. Assessing the possible interaction and optimization of process parameters including pH, sonication time, adsorbent mass and the concentration of adsorbates was carried out by response surface methodology based on central composite design (RSM-CCD). The isotherm experimental data were demonstrated to be great fitted with Langmuir isotherm model, and the maximum capacity values of adsorption in a ternary medium were 44.5 mg g−1, 62.1 mg g−1, and 25.2 mg g−1 for Co (II), MG, and IMI, respectively. A better description of the adsorption process was provided by using pseudo-second-order model, meaning that chemical adsorption controlled the process. In addition, the thermodynamic parameters illustrated that the adsorption of all contaminants occurred spontaneously and endothermically. MCS/AC@UiO-66 demonstrated to be a superb reusable adsorbent with a high adsorption capacity even after four adsorption–desorption cycles for the removal of all contaminants from various real wastewater samples. It was concluded that MCS/AC@UiO-66 with excellent properties, such as eco-friendly, easy synthesis, cost-effectiveness, fast adsorption kinetic, high adsorption efficiency, simple magnetic separation, and excellent reusability, could be considered as a promising candidate to remove a wide range of contaminants from wastewaters.
Recently, due to the increasing demand for energy and the identification of fossil fuels and their pollution, the focus on renewable energy is increasing day by day, so the use of renewable energy ...and energy-saving techniques is very important. PCMs are one of the most effective means of thermal energy storage, whose task is to change phase with increasing temperature, store thermal energy, and release this energy with decreasing temperature. This is one of the applications of these materials in building walls. In this research, the aim is to analyze and investigate the use of phase change materials in addition to thermal insulation. For this purpose, optimization in terms of energy and thermal comfort of residents has been done by the response surface method. Four Iranian cities with different climates—Tehran, Bandar Abbas, Tabriz, and Rasht—have undergone this optimization. According to the results, it can be concluded that the best temperature for the heating thermostat is approximately 20 °C and for the cooling thermostat, approximately 28 °C and 25 °C. Also, the best thermal insulation and PCMs are polyurethane and BioPCMDSCM27Q21. The thickness of the thermal insulation in the range between 6.9 cm and 9.8 cm is chosen as optimal, and the thickness of the phase change material is approximately 5 cm optimal for all cities (except Tehran). Due to the optimization of thermal comfort between 25 and 60 %, heating electricity between 43 and 99 % and cooling electricity between 38 and 52 % have been improved.
•This study deals with the use of PCM and thermal insulation in Iran, focusing on energy optimization and thermal comfort.•The best temperature for the heating thermostat is 20 °C and for the cooling thermostat 28 °C and 25 °C.•The best thermal insulation and phase change materials are polyurethane and BioPCMDSCM27Q21.•The optimal thickness of thermal insulation was obtained from 6.9 cm to 9.8 cm for all cities.•Thermal comfort 25-60 %, heating electricity 45-100 % and cooling electricity 40-53 % have been improved.
In this present work, effort was taken to develop a response surface model based on response surface methodology (RSM) paired with Box-Behnken design (BBD). Investigations were carried out to ...optimize the transesterification of Pongamia Pinnata oil (PPO) under various process conditions such as time (60-180 min), temperature (60 °C-100 °C), and catalyst (1%-3%). The production of PPO methyl ester (PPOME) by the esterification process is carried out using the PPO and methanol (CH3OH) in a 1:6 molar ratio that is fixed as a constant. Here, the input variables are the process variables (independent) and the output variables are the response variables (dependent). The response variables are the breakdown voltage (BDV), kinematic viscosity (KV), and fire point (FRP). The effect of the process variables on the response variables is modeled using RSM paired BBD. The experimental sequence was designed to find the optimum composition of input parameters and output parameters. The associative effects of the input and output variables were designed as a 2-D contour plot and 3-D response surface plots, and the interactive effects were studied using the plots. After optimization, the optimum conditions of the input variables over the BDV, KV, and FRP were found to be the time of 142.07 min, the temperature of 81.52 °C, and the catalyst of 2.41%. The dielectric properties of PPOME were found to be 61.54 kV, 20.50 cSt, and 281.43 °C, which are in the vicinity of the laboratory experimental results. Those indicate that the treatment of PPO with the optimum quantity of the process variables gives an excellent dielectric response.
