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One of the most critical issues faced by chemical industries is reducing the environmental impact caused due to pollution, which has resulted in global warming and health issues. Most chemical industries monitor and use Key Performance Indicators (KPIs) to control pollution, which is currently done by using various KPI’s that are dependent on the product they are producing. Therefore, a study is conducted using a systematic literature review (SLR) focused on articles published between 2000 and 2022 to identify and categorize various KPIs that manufacturers have used to reduce their respective pollution. The results were divided into four main categories – air, water, land, and other pollution. The results demonstrated that ethylene manufacturing industries are the major contributor to air pollution. The mining, gas, and oil industries significantly resulted in water pollution. The land and groundwater pollution were mainly due to mining industries. The other pollution was mainly due to activities such as maintenance and performance of equipment and quality of raw materials.

The cost of microalgae harvesting constitutes a heavy burden on the commercialization of biofuel production. The present study addressed this problem through economic and parametric comparison of electrochemical harvesting using a sacrificial electrode (aluminum) and a nonsacrificial electrode (graphite). The harvesting efficiency, power consumption, and operation cost were collected as objective variables as a function of applied current and initial pH of the solution. The results indicated that high harvesting efficiency obtained by using aluminum anode is achieved in short electrolysis time. That harvesting efficiency can be enhanced by increasing the applied current or the electrolysis time for both electrode materials, where 98% of harvesting efficiency can be obtained. The results also demonstrated that the power consumption with the graphite anode is higher than that of aluminum. However, at 0.2 A the local cost of operation with graphite (0.036 US$/m3) is distinctly lower than that of aluminum (0.08 US$/m3). Furthermore, the harvesting efficiency reached its higher value at short electrolysis time at an initial pH of 6 for aluminum, and at an initial pH of 4 for graphite. Consequently, the power consumption of the harvesting process could be reduced at acid- nature conditions to around 0.46 kWh/kg for aluminum and 1.12 kWh/kg for graphite.

Mango seed kernel oil (MSKO) contains a high concentration of polyphenol and has potential as raw material of oil-based food products and as a natural antioxidant of functional food. Ethanol was used for the extraction of MSKO by response surface methodology (RSM) as a tool to study the optimum extraction conditions of the oil yield and total polyphenol content (TPC). Three-factorthree- level central composite design (CCD) was employed to optimize extraction time (X1), ethanol concentration (X2), and ethanol volume (X3) to obtain a high oil yield and TPC. The central points for treatment were 5 h for X1, 86% for X2, and 250 mL for X3. The results showed that the optimum conditions of MSKO extraction were X1 = 5.18 h, X2 = 87.84% and X3 = 233.43 mL, respectively. Under these conditions, the experimental oil yield and TPC of MSKO were 34.79% and 61.17 mgGAE/g, which was agreed closely to the verification value. The results indicated that MSKO extraction using ethanol could be an effective and advisable method for large-scale production of MSKO extraction.

In recent years, many researchers have focused on microalgae as a potential source of lipids for various purposes. To improve the lipid yield, different biomass pretreatments have been investigated. The aim of this work was to determine the effect of an ultrasound and deep eutectic solvent (DES) pretreatment on lipid yield from green microalgae Chlorella sp. The chosen DESs were choline chloride:urea (ChCl:U), choline chloride:glycerol (ChCl:G), and choline chloride:acetic acid (ChCl:Aa) all at the molar ratio 1:2. Lipids were extracted from the pretreated and untreated biomasses by Bligh and Dyer’s method. The results showed that the lipid yields for the untreated and ultrasound-pretreated biomass were 39% and 48%, respectively. The pretreatments with ChCl:U, ChCl:G, and ChCl:Aa resulted in lipid yields of 51%, 46%, and 40%, respectively. Therefore, the use of efficient and environmentally friendly DESs for the microalgae biomass pretreatment resulted in a higher lipid yield.

The main purpose of this study was to research the influence of different drying methods on the physical and qualitative properties of dried shrimps. Shrimps were dried with conventional methods at 60, 70 and 80?C between 330 to 210 min and 190 to 110 min, in an oven and vacuum oven respectively. Drying time was shortened with the use of a vacuum pump. The drying kinetics of the shrimp were studied, and effective moisture diffusion and activation energy were calculated for both methods. The Alibas model and the Midilli and Kucuk model provided the best experimental data with a high coefficient of determination (R2) for the oven and vacuum oven techniques, respectively. The final dried products were characterized by investigating the color characteristics, heavy metal content and by carrying out protein analyses. The rehydration ratio was also determined for the dehydrated shrimps. Drying conditions affected the color features so that shrimps dried in ovens and vacuum ovens showed an increase in brightness and yellowness values and a decrease in redness values. The concentration of As, Pb, Cd, Hg, Cu, Zn and Fe in the dried shrimp were within acceptable limits. The protein content of dried shrimp (?85%) is higher than that of undried shrimp (?20%).

To produce biodiesel, one of the most important factors is the quality of the oil used in the production. However, other factors such as price and availability should also be taken into consideration. Chicken wastes oil shows a very promising option for this sector, since it comes from a waste. The aim of the present study was a methodology for extraction and characterization of chicken wastes oil for production of biodiesel by ethylic transesterification, besides presenting the characterization and optimization of the process variables of the production of biodiesel, the applying of RSM involving CCD. The investigation was performed following evaluation of the characterization parameters for the oil: viscosity, density, acidity index, moisture of the sample, refractive index, and saponification index. For biodiesel, viscosity, density, acidity index and ester content were evaluated. An optimum point was reached for the production of chicken biodiesel where the concentration of the catalyst is 2.1% by mass, the oil/ethanol ratio is 1:5.5 and the reaction temperature of 30 ?C; at that point, a 95% conversion was achieved. At the optimum point obtained from the statistical technique for a p-value of 0.05 the results found for the physical- chemical characterization of biodiesel are found in the ANP standards.

The study proposes the evaluation of the residence-time distribution (RTD) in situ in an industrial dryer for the production of recycled polyester fibers (PES) from colorless polyethylene terephthalate (PET) flakes without interruption of the production. A disturbance of the pulse type was employed, in which the tracer (blue PET flakes) had previously been crystalized and its concentration was obtained according to the time at the dryer outlet. Additionally, analyses of intrinsic viscosity and crystallization percentage of the PET flakes (colorless and blue) and PES intrinsic viscosity and color force were performed. By RTD, the mean residence time (322.8 min), the variance (1305.4 min2), the standard deviation (36.1 min) and the relative error (1.5%) were obtained when compared to the theoretical residence time, indicating the absence of preferred paths or flake agglomerates in the equipment. Finally, the characterization demonstrated that there was no alteration in the parameters of product quality during RTD evaluation, confirming the potential of application of this methodology for diagnoses of continuous industrial processes.

Quantitative structure-property relationship (QSPR) technique provides a suitable tool to predict the critical micelle concentration (CMC) of Gemini surfactants from their structure descriptors. In this study, a comparative work was conducted to model the CMC property of 211 diverse Gemini surfactants based on their structural characteristics using linear and non-linear quantitative structure?property relationship models. Least squares model (OLS) and partial least squares (PLS) against k-nearest neighbours regression model (KNN), artificial neural network (ANN) and support vector regression (SVR) have been developed to model the CMC. Molecular descriptors were calculated and screened to remove unsuitable descriptors and improve the learning. Results indicate that the improved performance of support vector regression when the hyper-parameters are optimized using Dragonfly algorithm (SVR-DA) was highly capable of predicting the pCMC (-log CMC) values with an average absolute relative deviation (AARD) of 0.666 and coefficient of determination (R?) of 0.9971 for the global dataset.

The deposition of paraffin wax from crude oil at low temperatures due to wax deposition, high pour point, high viscosity, and weak flow capability is among the critical and persisting challenges faced by the petroleum industry. In this study, a new para-decyloxy allyl benzoate (I10) was prepared, polymerized into HI10, and copolymerized with dioctadecyl maleate into MHI10 via the free-radical polymerization method employing azobisisobutyronitrile and toluene as the initiator and solvent, respectively. The prepared monomer was characterized by spectroscopic analyses (Fourier-transform infrared (FT-IR)) and proton nuclear magnetic resonance. Further, the polymers were characterized by FT-IR, and their average molecular weights were determined by gel permeation chromatography. The prepared compounds were taken in different concentrations and then tested as flow improvers of Qarun waxy crude oil using pour point depression and rheological parameters. The results of this test indicated that MHI10 exerted the highest effect on pour point reduction and the rheological parameters (yield value and apparent viscosity). Moreover, an increase in the efficiency of the additives was observed after increasing their concentration from 1000 to 5000 ppm.

Simulations were performed under continuous processing conditions using the 2D continuum model to describe the internal state of a multi-solid system, comprising solid particles of different sizes and densities at the same time. The feed consisted of 35 types of solid particle species with five different sizes, 1.70, 1.20, 0.85, 0.60 and 0.35 mm, and seven different densities ranging from 1400 to 2000 kg/m3. The simulations results have been used to plot the concentration profiles of solid particles along the bed height. The concentration profiles of the solid particles depicted that the fine dense particles, 0.60 mm, having density equal to 1900 kg/m3 and terminal velocity 0.058 m/s moved downwards and discharged into the underflow. However, the low-density coarse particles, 1.20 mm, having density equal to 1400 kg/m3 and terminal velocity 0.068 m/s moved upwards and conveyed to the overflow, hence, show a separation process based on the density difference. Furthermore, simulation results showed that the particle species having densities close to the value of the separation relative density exhibited higher concentrations along the system height, and the suspension within the system was mainly composed of these species.

This work designed, modeled and performed economic analysis of the base case extraction and recovery of catechin mix (CM) from Camellia sinensis leaves (CSL) using deep eutectic solvent (DES) and microwave assisted extraction (MAE) with the assistance of SuperPro Designer software. Techno-economic analysis of three commercial scales of manufacture was also investigated and compared using profitability parameters. Sensitivity and uncertainty analyses were further carried out on the most viable commercial scale to determine input variable (s) of highest significance on the profitability of the process. The 3.30 kg CM/batch is the most economically desirable scale with return on investment of 324.65%, payback period of 0.31 year, internal rate of return of 163.83% and net present value of 1,059,595,224. Out of the input variables selected for the sensitivity and uncertainty analyses, CSL and DES costs have the least effect on the selected profitability parameters of the process.

High content of magnesium in phosphate and phosphoric acid affects negatively the performance and operating conditions in phosphate industry. A content of more than 0.3% in phosphate increases the P2O5 losses during phosphate digestion and filtration, and also increases steam consumption and solid settling kinetics during concentration. In this work, the removal of magnesium from phosphoric acid by precipitation in one of the compounds, MgAlF5 or MgAl2F8, was studied. Magnesium precipitation is achieved by the simultaneous addition of aluminum and fluorine. The experimental design methodology was used to carry out this work. Tests were conducted according to the NEMRODW software using industrial quality phosphoric acid. The screening study of parameters affecting the removal efficiency of magnesium from industrial wet phosphoric acid showed that from the following parameters: temperature, F/Mg and Al/Mg ratios, aluminum form and fluorine form, only temperature and F/Mg ratio have an effective influence on magnesium removal. The optimization of magnesium removal from phosphoric acid was performed according to the response surface methodology using a composite matrix. By applying this methodology, the optimum parameters corresponding to a maximum magnesium removal efficiency in phosphoric acid were determined. The values of the optimum parameters obtained by this method are T = 80 ?C, ratios: Al/Mg = 1 and F/Mg = 16.

The input parameters, empirical, and semi-empirical models significantly influence the responses obtained by CFD-DEM simulations. In this work, the effects of three turbulence models, three conditions of the particle rotation, and five drag models, on the fluid dynamic behavior of a conical spout bed applied to the drying of sorghum grains were evaluated. Experimental data on the solids pressure drop, height, and shape of the fountain were used to validate the simulations. Results showed the importance of including the particle rotation in the model to approximate the results simulated with the experimental behavior. Compared with experimental data, considering the particle rotation by the Dennis et al. model, the deviation was 2% for the fountain height and 9.18% for the pressure drop. Whereas, for the model without the particle rotation, the deviations were 106.33 and 42.31% for the fountain height and pressure drop, respectively. For the analyzed case, the standard k-? turbulence model showed a greater agreement with the experimental data. For the drag models evaluated, the best fit with the experimental data was obtained by the Koch-Hill drag model, followed by the Gidaspow model, with deviations less than 10%.

The effects of different additives, including MgSO4, MnSO4, adipic acid, citric acid, benzoic acid, succinic acid and acrylic acid on SO2 removal from a limestone-gypsum wet flue gas desulfurization (FGD) system and gypsum characteristics were investigated. An optimized formulation additive for simultaneously improving flue gas desulfurization efficiency and gypsum quality was found. This formulation additive was successfully applied in an industrial-scale FGD system of a local coal power plant (600 MW, Shanghai Wujing Power Plant, China), and the gypsum quality was improved. The optimized formulation additive was acrylic acid, MnSO4 and citric acid mixed at a ratio of 1:1:2, which can simultaneously achieve an increased desulfurization efficiency of 97.02% and a low gypsum moisture content of 4.32%. Moreover, MnSO4 and acrylic acid were found to be most effective for improving SO2 removal, and citric acid contributed to gypsum particles with more uniform sizes and regular shapes, as well as good dewatering characteristics.

Methane (CH4) and carbon dioxide (CO2) are greenhouse gases that have been converted into synthesis gas for the production of oxygenated chemicals and hydrocarbons. In this paper, M(Ca, Ba, Sr)xLa1-xNiO3 (x=0.0, 0.3 and 0.5) doped perovskites were successfully synthesized as catalyst precursors aiming at high catalytic activity and stability in the CO2 reforming of methane. These perovskites were characterized by X-ray diffraction (XRD), temperature programmed reduction by H2 (H2-TPR) and O2-temperature programmed oxidation (TPO). Its activity and carbon suppression were investigated in the CO2 reforming of methane. Results showed formation of perovskite structure, but La2NiO4 spinel and NiO were also detected in doped perovskites. The Ca, Ba and Sr partial substitution has evident influence on the reduction behavior of perovskites. All the doped perovskites used as catalyst precursors had better catalytic performance than LaNiO3. However, increasing the doping content decreased activity. Among doped perovskites, Ca0.3La0.7NiO3 showed better catalytic performance for the methane reforming reaction.

In this study, hemicellulose based polymeric gel films were synthesized using the free radical polymerization mechanism. Hemicellulose was obtained from waste tea leaf brewing waste by using delignification process. Polymeric gel films were produced in accordance with solution-casting technique. The effect of synthesis parameters were investigated on the structure and properties of gel films. For this purpose, the hemicellulose based synthesized gel films were characterized by analytical test. Experimental results indicated that hemicellulose based gel films were absorbed moisture in the rate of maximum 1% in 100 % relative humidity environment. The lowest water vapor permeability (WVP) value was measured to be 5.88×10-10 g/s.Pa.m, for the hemicellulose based film including chitosan. The average solubility values of the produced polymeric films varied between approximately 0.4 % and 1.8 %. It was observed that the optical transparency of hemicellulose based polymeric gel films changed from about 45 % to 65 % and the opacity/thickness values are from 0.0027-0.0011 μm-1. As a result, it has been found that the physicochemical and morphological properties of the synthesized films are greatly influenced by the composition of the films.

The discovery of a natural gas field in the 1950s was a major event. These resources contained in the subsoil of a village at the foot of the Pyrenees provided energy for the national industrial development. Hence, the intervention and investments of the State and the largest national companies. We analyzed the ex nihilo creation, around the production units of the SNPA (Société Nationale des Pétroles d’Aquitaine), which exploited the area, of an industrial facility that wanted to take advantage of the natural gas of Lacq, very loaded with sulfur as a raw material or as a source of energy to produce electricity. In less than five years a rural region underwent a total metamorphosis; the Lacq-Mourenx district was the second most heavily industrialized area in the south-west of the country. The article also evaluates the strategies of anticipation to the foreseeable exhaustion of the place. El descubrimiento de un yacimiento de gas natural en los años 1950 fue un evento de gran magnitud. Estos recursos contenidos en el subsuelo de un pueblo a pie de los Pireneos daban energía para el desarrolismo industrial nacional. De ahi, la intervención y las inversiones del Estado y de las grandes empresas nacionales. Analizamos la creación ex nihilo, alrededor de las unidades de producción de la SNPA (Société Nationale des Pétroles d’Aquitaine), explotadora del yacimiento, de un complejo industrial que quería aprovechar el gas natural de Lacq, muy cargado en azufre como materia prima o como fuente de energía para producir electricidad. En menos de cinco años una comarca rural experimentó una metamorfosis total; el distrito de Lacq-Mourenx era la segunda zona mas intensamente industrializada del suroeste del país. El artículo también evalua las estrategías de anticipación al previsible agotamiento del yacimiento.

PurposeThe study seeks to apply Web co‐word analysis to the Chinese business environment to test the feasibility of the method there.Design/methodology/approachThe authors selected a group of companies in two Chinese industries, collected co‐word data for the companies, analyzed the data with multidimensional scaling (MDS), and then compared the MDS maps generated from the co‐word data with business situations to find out if the co‐word method works.FindingsThe study found that the Web co‐word method could potentially be applied to the Chinese environment. The study also found the advantages and disadvantages of the Web co‐word method vs the Web co‐link method.Originality/valueKnowing the applicability of the Web co‐word method to the Chinese environment contributes to the knowledge of this new Webometrics method. Mining business information from the Web is more valuable when applied to a foreign country where language and culture barriers exist. To use the co‐word method, one does not have to be able to read or write in that language. One only needs to have the names of the companies to study, which can be easily obtained without knowledge of the language. The value of business information about countries such as China is obvious given the global nature of contemporary business competition and the significance of the Chinese economy to the world.