•The semi-industrial pilot of the microreactor was optimized in the synthesis of biodiesel.•KOH/Clinoptilolite was used as a catalyst for biodiesel production from waste cooking oil.•At optimized ...conditions, the biodiesel purity was experimentally found to be 97.45%.
In this study, the transesterification of waste cooking oil and methanol aimed to produce biodiesel and use of KOH/Clinoptilolite as a heterogeneous catalyst in the microreactor as a new reactor to accelerate this process. Therefore, a semi-industrial pilot was investigated under different conditions for biodiesel production and optimizing the operating conditions. In order to optimize these conditions, the effect of important factors was studied including reaction temperature, catalyst concentration, volume ratio of oil-to-methanol and residence time on the purity of biodiesel produced through response surface methodology (RSM). After data analysis and optimizing the reaction of biodiesel production, the highest purity of produced biodiesel was obtained at reaction temperature of 65 °C, catalyst concentration of 8.1 wt%, oil/methanol volume ratio of 2.25:1 and residence time of 13.4 min which resulted in a biodiesel production with a purity of 97.45%. Based on the results, the use of microchannel can reduce the reaction time by the increase of mixing. Further, the cost of biodiesel production can be reduced using waste cooking oil and KOH/Clinoptilolite.
This study aimed to evaluate and optimize a pilot-scale microreactor to convert waste cooking oil (WCO) into biodiesel using kettle limescale. Box-Behnken design was used to determine the optimum ...conditions for producing biodiesel. Effects of main variables including reaction temperature, catalyst concentration, and alcohol/oil volume ratio were evaluated at a constant residence time of 10 min. Based on the results of analysis of variance, the quadratic regression model had the best coefficient of determination (R2=0.9930) and adjusted coefficient of determination (RAdj.2= 0.9804). After the optimization of temperature, catalyst concentration, and methanol/oil volume ratio, the residence time was optimized to achieve the maximum purity of the produced biodiesel. At a reaction temperature of 61.7 °C, catalysts concentration (oil based) of 8.87 wt %, methanol to oil volume ratio of 1.7:3, and a residence time of 15 min, we observed the optimal conditions for obtaining a maximum biodiesel purity of 93.41%.
•In a pilot-scale microreactor waste cooking oil was converted to biodiesel.•Kettle limescale was used as a heterogeneous catalyst in transesterification reaction.•In the optimal conditions maximum biodiesel purity was obtained 93.41%.•Box-Behnken experimental design was used to determine the optimal conditions.
Purpose: Apple fruit widely suffers from different damages every year including post-harvest diseases such as blue mold (caused by Penicillium expansum). Recent studies have shown the role of ...hormones in different signaling pathways after a pathogen attack. Hormones may trigger different the expression of genes involved in the resistance mechanism and thus activating the immune system in plants. Findings: qRT-PCR results showed an increase in the expression of PR5, ERF1 and CHIB genes after treatment with BABA in both Golden Delicious and Fuji cultivars. ACC treatment also significantly increased the expression of ERF1 and CHIB genes after challenged with fungal spores. The expression of PR5 and ERF1 was relatively very similar in both cultivars after treatment with BABA and ACC, respectively. In contrast, the expression of CHIB was different in two cultivars, thus showing a 4 times higher expression in Golden delicious in compared to Fuji. Originality/Value: Using of new insecticides with new and widespread mode of action can be recommended against postharvest pest in the practical entomology. Research limitations: No limitations were found. Originality/value: The results of this study can be important in breeding studies and to select genes involved in the resistance mechanism. In addition, hormones with a positive impact to provide resistance to fungal diseases can be considered as a possible alternative to fungicides.
This study investigated the transesterification of waste cooking oil (WCO) with methanol in the presence of potassium hydroxide as the catalyst. A semi-industrial pilot of microreactor with 50 tubes ...with a diameter of 0.8 mm was used to produce 5 L/h biodiesel. Initially, the acidity of waste cooking oil was reduced to less than 1 mg KOH/g oil by using methanol at 60 °C in the presence of 1% sulfuric acid. Using Box-Behnken design method, the effects of methanol to oil molar ratio (6:1–12:1), catalyst weight (0.5–1.5 wt %), and reaction temperature (55–65 °C) were studied. The methanol to oil molar ratio of 9.4:1, the catalyst concentration of 1.16 wt %, and the reaction temperature of 62.4 °C was achieved under optimum condition. Finally, the effect of reaction time (30–120 s) was examined at the optimum condition. The highest level of biodiesel purity or fatty acid methyl esters % (FAMEs %) was 98.26%. In addition, the properties of produced biodiesel were determined and compared with those of the standard ASTM D6751.
•Semi-industrial pilot of microreactor was used in the synthesis of biodiesel.•Potassium hydroxide was used as catalyst for biodiesel production from waste cooking oil.•The influence of methanol to oil molar ratio (MR), catalyst concentration (C), and temperature were evaluated and optimized.•The biodiesel purity value was obtained 98.26%. with residence time 120 s.
•The semi-industrial pilot of the microreactor was optimized in the synthesis of biodiesel.•Acetone was used as a co-solvent for the transesterification reaction.•At optimized conditions, biodiesel ...purity was experimentally within 12.5 min attained to be 97.16%.
The development and use of new technologies for the amplification of the biodiesel production process in the transesterification reaction, which improves the mixing between the two phases, has led to the development and use of new reactors, including micro-reactors. Hence, the present study aimed at investigating the performance of a semi-industrial microreactor in the production of biodiesel from waste cooking oil (WCO) with methanol. The process was carried out through transesterification using acetone as the co-solvent at the presence of limescale (kettle limescale deposit) under different conditions. To optimize the reaction conditions, the main parameters affecting the purity of produced biodiesel, including residence time, reaction temperature, methanol to oil volume ratio, and acetone concentration (oil-based) were studied via response surface methodology (RSM). The best performance in biodiesel production was observed at a residence time of 12.5 min, reaction temperature of 60 °C, methanol to oil volume ratio of 2.15:5, and acetone concentration (pure oil-based) of 13.95 wt%, which resulted in a biodiesel purity of 97.16%. According to the results, the utilization of kettle limescale deposits as the catalyst and acetone as the co-solvent can help to reduce reaction time and production cost.
•Different alcoholic solvents were considered with monoethanolamine for CO2 absorption.•The effects of temperature, solvent flow rate, and solvent concentration on CO2 desorption were studied.•The ...lowest energy consumed for CO2 desorption in the microreactor was obtained by methanol (0.41 MJ/kg).
In this work, mixtures of monoethanolamine with four different alcoholic solvents of methanol, ethanol, propanol, and butanol were used for carbon dioxide (CO2) absorption in a microreactor. These alcoholic mixtures were compared with a mixture of monoethanolamine and water, as this is one of the common solvents in this field. To this objective, the effect of three operating parameters, desorption temperature from 55 °C to 95 °C, the solvent flow rate from 1 mL/min to 5 mL/min, and solvent concentration from 10% to 50%, were investigated on the process of CO2 desorption in the microreactor. Furthermore, the amount of energy consumed per kilogram of CO2 desorption (E) by solvents including methanol, ethanol, propanol, butanol, and water was measured to determine the rate of desorption and energy consumption. The results showed that alcoholic solvents reduced E by more than one-third. This is more than water, which is most widely used solvent for monoethanolamine. Also, using a microreactor as a piece of genuine mass transfer equipment during the desorption process reduced energy consumption significantly. Finally, the results show that the lowest E was for the solvent of monoethanolamine + methanol, which under optimal conditions is 0.41 MJ per kg desorbed CO2 (MJ.kg-of-CO2−1). The values for the solvents of monoethanolamine + ethanol, monoethanolamine + propanol, monoethanolamine + butanol were 0.48, 0.55, and 1.1 MJ.kg-of-CO2−1, respectively. However, the values for the solvent of monoethanolamine + water in the microreactor were obtained at the optimum operating condition of about 1.39 MJ.kg-of-CO2−1.
•The effects of temperature, solvent flow rate, and gas flow rate on CO2 absorption.•Four primary alcohols and two glycols were used as a solvent.•A micro-reactor with a diameter of 800 µm and length ...of 25 cm was used.
Carbon dioxide absorption using solvents is a critical process in mitigating greenhouse gas emissions. The monoethanolamine (MEA) + water (30 wt.%) mixture is the most commonly used solvent, but alternative solvents with better performance are desired.
This study investigated the effects of temperature, solvent flow rate, and gas flow rate on carbon dioxide absorption and liquid-side volumetric mass transfer coefficient in a microreactor using various solvents. The performance of the tested solvents was compared to the MEA + water (30 wt.%) mixture.
Ethylene glycol achieved the highest absorption (91.57%) at 15 °C, with a solvent flow rate of 0.05 l.min−1 and a gas flow rate of 1 l.min−1. The maximum klav value of 18.2 s−1 was reached at 15 °C, with a solvent flow rate of 0.01 l.min−1 and a gas flow rate of 1 l.min−1. This value was 1.3 times higher than that of the MEA + water (30 wt.%) mixture under similar conditions, indicating the potential to replace glycolytic solvents with amine-based solvents in carbon dioxide absorption applications.
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In this work, high-performance, low-cost, environmentally friendly multilayered solar steam generation systems are fabricated by engineering the structure and using a biomass photothermal material. ...Remarkably, the biomass photothermal material is extracted from the pyrolysis waste of linseed (flax) grains. The introduced system desalinates water using solar energy as the renewable source of energy, and its light absorber is from the waste of a renewable source. The biomass waste powder possesses a mesoporous structure, providing high light absorption through photon scattering and its high surface area. Moreover, to harvest the incident light efficiently and manage the thermal energy generated, devices including light absorbers with cone and cubic configurations and different water manager layers are fabricated and compared to each other. To confirm the high performance of the introduced photothermal material, different systems comprising graphite, graphene oxide, and carbon nanotube light absorbers are also fabricated. Using a biomass light absorber combined with harvesting of the light in different directions (cone configuration), the system with a water evaporation rate of 1.59 kg/m2h corresponding to an efficiency of 92.9% is achieved. Furthermore, by depositing a thin layer of the transparent thermal superinsulator silica aerogel on the light absorber layer, the generated heat is localized and the heat losses are prevented, leading to a 7.5% enhancement of the water evaporation rate of the biomass system. The eco-friendly biomass-based system shows no significant change in its performance through operation for 40 desalination cycles of Persian Gulf water.
Fatty masses of the heart are relatively uncommon. This report is about an extremely rare case of cardiac lipomatosis that implicates both ventricles and inter-atrial septum. The patient was a ...27-year-old female who was accidentally diagnosed during a routine physical examination. Trans-thoracic echocardiography (TTE) discovered a large homogenous bi-lobed, non-encapsulated echogenic mass. Magnetic resonance imaging (MRI) showed soft tissue abnormal enhancement in the anterior left base of the heart and sub-aortic outflow tract. A trans-jugular echomyocardial biopsy was done because of a lack of a definite diagnosis by non-invasive techniques. Pathological study showed benign fatty infiltration suggestive for benign lipomatous hypertrophy.
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