Solvent Feed Ratios Research Articles

The role of microwave radiation in extractive desulfurization of real diesel fuel for green environment: an experimental and computational investigation

The process of removing sulfur compounds and aromatic compounds to produce clean fuel is an important and effective contribution to the processes of mitigating and adapting to climate change. In contrast, it is necessary to find an innovative way to remove sulfur and carcinogenic aromatic compounds because clean, low-sulfur diesel is commonly used in all countries of the world at the present time. Therefore, in this work, we have studied the effect of the microwave radiation power and the irradiation time with the use of more than one type of organic solvent; methanol, acetonitrile and ethyl acetoacetate; as an extractant and solvent to feed ratio impact on the removal of sulfur and aromatic compounds of a real diesel fuel feed which has 450 ppm sulfur content and 16 wt% aromatic Content. The results showed that the best solvent used during this work was ethyl acetoacetate. According to the results, high sulfur removal (≈ 92%) was accomplished with microwave-assisted extractive desulfurization technique under the following ideal conditions: the irradiation time is 7 min, the solvent feed ratio is 3:1 and the microwave intensity is 180 W. To reveal the mechanism of microwave-assisted extractive desulfurization via different organic solvents, a theoretical study including structural examination and interaction energy analysis on the interaction between dibenzothiophene (DBT) or dimethyl dibenzothiophene (DMDBT) and the different organic solvents was also conducted.

Effect of pulsed ultrasound assisted extraction and aqueous acetone mixture on total hydrolysable tannins from pomegranate peel

Pomegranate peels are disposed of as waste even though it is an eminent source of total hydrolysable tannins (THT) and possesses a great worth for recycling. The present study was carried out with the hypothesis that pulsed system ultrasound-assisted extraction (PSUAE) technique optimization would aid in retaining high extract yield and THT recovery yield from pomegranate peel extract (PPE) with enhanced antioxidant potential. The extraction was performed at various conditions regarding solvent concentration (30–90% of acetone), solvent-feed ratio (10–30 mL/g), extraction time (10–20 min), and ultrasound amplitude (40–80%) for maximum extract yield, THT and antioxidant activity (AA). To model and optimize the process conditions tools namely response surface methodology (RSM) and artificial neural network (ANN) were applied. For solvent concentration, solvent-feed ratio, extraction time, and amplitude the optimal conditions attained with aid of RSM and ANN were: 56%, 26.5 mL/g, 15 min, 55%, and 45%, 23 mL/g, 15 min, 50% respectively. The extract yield and THT content determined with RSM and ANN optimized values were 51.2%, 86.4 mg TAE/g, and 62%, 98.1 mg TAE/g, respectively. The mean square error value displayed the minimum and R2 exhibited maximum value in case of ANN compared to RSM model. PSUAE significantly augmented the AA of PPE to 77.2 ± 0.50% compared to 49.7 ± 0.35% of conventional extraction. FTIR and HPLC analysis established that PPE produced from PSUAE contains a significant amount of THT compounds (gallic acid and tannic acid derivative). SEM elucidated that the sonication effect resulted in peel cell wall disruptions ensuing in elevated extraction of THT. Therefore, this pulsed mode of ultrasound extraction could be regarded as an easy, cost-effective, and competent technique for the extraction of preferred natural THT from pomegranate peels that possess high prospective to be applied in food and nutraceutical formulations.

Multi-step reflux extraction of bio-pharmaceutical phenolic bioactives from balsam apple (Momordica balsamina L.)

In this study, the impacts of parameter combinations on the response (total phenolic yield) were evaluated using the single experiments and two-level factorial design. The investigated parameters with their value range include; the microwave extraction time (1–5 min), power level (400–600 W), temperature (60–80°C), the solvent-feed ratio, SFR (8–12 mL/g) and solvent concentration (50–80%). The result of this investigation succinctly presented the solvent concentration as the highest contributing parameters, far above the Bonferroni limit (8.37517) and t-value limit (3.18245). However, the temperature, SFR and microwave duration provided insignificant contribution to the response settings. The result of the spectrometry chromatographic analysis identified 22 phenolics compounds from the extracts which invariably revealed their potential biological functions. The study therefore adequately elucidated the contributing factor in the microwave recovery of total phenolic constituents from the M. balsamina leaves with potential use as scale-up parameters in drug applications.

Simplified Conceptual Design Methodology for Double-Feed Extractive Distillation Processes

Shortcut methods have an important role in the conceptual design of distillation processes because they rapidly provide constraints for important design parameters such as minimum reflux ratio, number of stages, process feasibility, possible splits, and, specifically for extractive distillation, minimum solvent feed ratio and maximum reflux ratio. In this work, a simplified method using reversible distillation models has been applied to the conceptual design of double feed extractive distillation columns. This work uses continuation methods for calculating the curves that determine the feasibility region and all of the resulting design parameters. Combining continuation methods with the column equations yields a simple method for calculating the pinch curves that border the feasibility region. As previously found by other authors, we observed that these extractive distillation pinch curves, in addition to determining the feasibility region, are also useful for calculating an approximate minimum entrainer feed ratio independent of other parameters, as well as accurately pinpointing the minimum and maximum reflux ratios. Applications to example extractive distillation systems allow us to conclude that the method is reliable, fast, and much easier to implement than other methods presented previously in the literature. The systems acetone–methanol–water and ethanol–water–ethylene glycol were employed as case studies, allowing a graphical assessment of the method; however, it can be used in the analysis of systems with more than three components.

Intensification and improvement of petrolatum deoiling process by using pure n-alkanes as non-polar modifiers

In order to intensify and improve the deoiling process, Alexandria crude petrolatum was subjected to one-stage fractional crystallization (deoiling process) using butyl acetate and methyl isobutyl ketone solvents at different solvent feed ratios of dilution ranging from 2:1 to 8:1 at fixed washing solvent ratio of 2:1 and ambient fractionating temperature of 20°C to produce micro-crystalline waxes. Non-polar modifiers such as individual pure n-alkanes with an even number of carbon atoms such as C20H42, C22H46 and C24H50 were added to the petrolatum deoiling solvent mixture in the percentages ranging from 0.05 to 1wt.% based on the feed to intensify petrolatum deoiling. Two tools of analysis such as XRD and SEM, beside the physical characteristics, were used to compare the crystal size and to observe the surface, shape and holes between crystals of the hard waxes separated without and with modifiers. Data revealed that, microcrystalline waxes with high quality are produced by using butyl acetate solvent at dilution and washing solvent ratios of 8:1 and 2:1 by weight, respectively with the addition of 1wt.% of a non-polar modifier; C20–24n-alkanes. The results are the increase of the filtration rate, growth of crystal size with more holes between the large crystals and improvement in the physical characteristics of the separated wax.

Competitive study on separation and characterization of microcrystalline waxes using two deoiling techniques

One stage fractional crystallization and solvent extraction techniques have been used to separate different microcrystalline waxes grades with different characteristics from Suez crude petrolatum. One stage fractional crystallization has been done using butyl acetate as solvent at ambient temperature of 20°C, at different dilution solvent ratios (S/F by weight) ranging from 2:1 to 8:1 and constant washing ratio of 2:1. While, solvent extraction technique has been done at different extraction temperatures and different solvent feed ratios (S/F by weight). The extraction solvents used are dimethyl-sulfoxide (DMS), N, N, dimethyl-acetamide (DMA), and N-methyl-2-pyrrolidone (NMP). The wax products are evaluated according to TAPPI-ASTM equation and petroleum wax specifications. The data revealed that solvent extraction technique is more suitable for deoiling Suez crude petrolatum than one stage fractional crystallization technique. Also, the resulting data revealed that DMA and NMP are suitable extracting solvents for isolating of microcrystalline waxes from Suez crude petrolatum. But, according to petroleum wax specifications, DMS is not a suitable solvent for separation of microcrystalline wax from Suez crude petrolatum.

Combination of Rigorous and Statistical Modeling for Process Development of Plant‐Based Extractions Based on Mass Balances and Biological Aspects

AbstractA rigorous model supported by botanical investigations has been developed to predict percolation results. Botanical investigations provide needed modeling parameters like pore size, porosity, or target compound distributions over the particle. After determining the desorption isotherm with maceration experiments at different solvent‐feed ratios, the model is validated with short residence time percolation experiments. With the aid of this validated model, percolation experiments with long residence times can be predicted and different process scenarios calculated. A combination of design of experiments and rigorous modeling together with standard equipment and experimental model parameter determination provides a fast and robust experimental design on the one hand and the precondition for a process parameter data‐based learning curve on the basis of rigorous modeling in the mid‐ or long‐term on the other hand.

Separation of some paraffin wax grades using solvent extraction technique

Solvent extraction technique has been used to separate paraffin wax grades; with different characteristics; from El-Ameria light, middle and heavy slack waxes. The wax deoiling has been done by solvent extraction at different extraction temperatures and different solvent feed ratios (S/F by weight). The extraction solvents used are furfural, N-methyl-2-pyrrolidone (NMP) and N, N, dimethylacetamide (DMA). The wax products are evaluated according to TAPPI-ASTM equation and petroleum wax specifications. The data revealed that DMA and NMP are suitable extracting solvents for isolating of semi- and scale-refined grades of paraffin waxes from light and middle slack waxes. But furfural solvent can separate only semi-microcrystalline waxes from heavy slack wax.

Effect of Flow Improvers on the Rheological Properties of Gas Oil and Gas Oil Raffinate

The gas-oil feedstock was solvent extracted with pyrrolidone (NMP) at different temperatures (50°C–70°C) and at different solvent feed ratios (ranging from 2/1 to 5/1). The raffinates were treated with four flow improver additives—two synthesized improvers (poly NAFOL 1822C palmitate-Co-N,N ditallowamine phthalic diamide and poly NAFOL 1822C palmitate Co-N,N ethanolamine phthalic diamide) and two available commercial improvers 2437 (Com. 1) and commercial wax dispersant CWD-11 (Com. 2) to study their efficiencies and suitabilities for improving the rheological properties. The efficiency of the additives in reducing the pour point of gas oil and their raffinates is in the order: Sec. > Et. > Com. 1 > Com. 2.

Effect of Flow Improvers on the Rheological Properties of Gas Oil and Their Raffinates

The gas oil feedstock was solvent extracted with pyrrolidone (NMP) at different temperatures (50°C–70°C) and at different solvent feed ratios (ranging from 2/1 to 5/1.) The raffinates were treated with four flow improvers additives; two synthesized improvers (poly NAFOL 1822C palmitate-Co-N,N ditallowamine phthalic diamide and poly NAFOL 1822C palmitate Co-N,N ethanolamine phthalic diamide) and two available commercial improvers 2437 (Com.1) & commercial wax dispersant CWD-11 (Com.2) to study their efficiencies and suitabilities for improving the rheological properties. The efficiency of the additives in reducing the pour point of gas oil and their raffinates is in the order: Sec > Et > Com1 > Com2.

Producing fuel alcohol by extractive distillation: Simulating the process with glycerol

Downstream separation processes in biotechnology form part of the stages having most impact on a product's final cost. The tendency throughout the world today is to replace fossil fuels with those having a renewable origin such as ethanol; this, in turn, produces a demand for the same and the need for optimising fermentation, treating vinazas and dehydration processes. The present work approaches the problem of dehydration through simulating azeotropic ethanol extractive distillation using glycerol as separation agent. Simulations were done on an Aspen Plus process simulator (Aspen Tech version 11.1). The simulated process involves two distillation columns, a dehydrator and a glycerol recuperation column. Simulation restrictions were ethanol's molar composition in dehydrator column distillate and the process's energy consumption. The effect of molar reflux ratio, solvent-feed ratio, solvent entry and feed stage and solvent entry temperature were evaluated on the chosen restrictions. The results showed that the ethanol-water mixture dehydration with glycerol as separation agent is efficient from the energy point of view.

Removal of Pollutants from Solid Matrices Using Supercritical Fluids

Abstract Several supercritical fluid extraction (SCFE) processes have been proposed for removing toxic and intractable organic compounds from a range of contaminated solids. These include soil remediation and the regeneration of adsorbents used to treat wastewater streams such as granular activated carbon (GAC). As a separation technique for environmental control, SCFE has several distinct advantages over conventional liquid extraction methods and incineration. Most notably, the contaminant is removed from the solvent in a concentrated form via a change in pressure or temperature and can be completely separated upon expansion to atmospheric pressure. The viability of SCFE hinges on process conditions such as solvent-feed ratio and solvent recycle ratio. The necessity of recycling solvent complicates the contaminant separation step since a complete reduction to atmospheric pressure would create large recompression costs. Because of this, the pressure and temperature dependence of contaminant solubility mus...