Conventional Extraction Process Research Articles

Terephthalaldehyde-Phenolic Resins as a Solid-Phase Extraction System for the Recovery of Rare-Earth Elements.

Rare-earth elements (REEs) are involved in most high technology devices and have become critical for many countries. The progress of processes for the extraction and recovery of REEs is therefore essential. Liquid–solid extraction methods are an attractive alternative to the conventional solvent extraction process used for the separation and/or purification of REEs. For this purpose, a solid-phase extraction system was investigated for the extraction and valorization of REEs. Ion-exchange resins were synthesized involving the condensation of terephthalaldehyde with resorcinol under alkaline conditions. The terephthalaldehyde, which is a non-hazardous aromatic dialdehyde, was used as an alternative to formaldehyde that is toxic and traditionally involved to prepare phenolic ion-exchange resins. The resulting formaldehyde-free resole-type phenolic resins were characterized and their ion-exchange capacity was investigated in regard to the extraction of rare-earth elements. We herein present a promising formaldehyde and phenol-free as a potential candidate for solid–liquid extraction REE with a capacity higher than 50 mg/g and the possibility to back-extract the REEs by a striping step using a 2 M HNO3 solution.

Ultrasound‐assisted extraction of anthocyanin from black rice bran using natural deep eutectic solvents: Optimization, diffusivity, and stability

The present study was aimed to establish a green extraction method for anthocyanins from black rice bran using natural deep eutectic solvents (NADES) coupled with ultrasound-assisted extraction (UAE). Initially, five NADES were used and lactic acid: fructose was screened as an efficient extractant for anthocyanin from black rice bran. The extraction condition was optimized using an artificial neural network-genetic algorithm and the best condition was found to be time 11.25 min, water 12.63%, solvent-to-solid ratio 18.75 ml/g, amplitude 21.31%. The UAE-NADES extraction kinetics of anthocyanin was suitable for the pseudo second order model (0.94 ≤ R2 ≤ 0.99). The UAE-NADES showed higher effective diffusivity (1.14 × 10–12 m/s2) of anthocyanin than the conventional extraction process. The enthalpy, entropy, and Gibbs free energy were negative irrespective of temperature. The stability of anthocyanin in NADES was higher than aqueous medium. This result indicates that the proposed method is an excellent alternative for the extraction and stabilization of anthocyanin. Practical applications Anthocyanin pigments are used as food colorants, antioxidants, and anticancer agents. However, anthocyanin is sensitive to processing factors, and the majority of regularly used extractant solvents are hazardous to the environment and reduce anthocyanin stability. The present study demonstrated that using a natural deep eutectic solvent to extract anthocyanin minimizes pollutants, lowers expenses, and improves extraction efficiency. Moreover, the study also demonstrated the non-thermal extraction as well as valorization of black rice bran.

Eco-efficient heat-integrated extractive distillation process using ionic liquid as entrainer for ethyl acetate-isopropyl alcohol-water mixture

Ethyl acetate-isopropyl alcohol-water is a common ternary mixture in pharmaceutical and chemical industries, containing multiple binary minimum azeotropes. Highly efficient separation for this mixture is of great significance to reduce environmental risk, recover valuable resource and maintain eco-sustainability. In this work, various enhanced extractive distillation processes using ionic liquid (IL) as entrainer are compared with conventional extractive distillation process (CED) in terms of the reductions of cost, energy and carbon emissions. First of all, ethylene glycol (EG) and 1-ethyl-3-methylimidazolium acetate ([BMIM][OAC]) as the most promising conventional and IL entrainers are screening out through quantum chemistry calculation based on COSMO-SAC model. Secondly, two methods of improving energy efficiency such as differential pressure heat integration and divided-wall column are applied to the CED process. Finally, the resulting six configurations are optimized by simulated annealing algorithm, taking minimum total annual cost (TAC) as goal, and subsequently evaluated from four aspects of TAC, annual capital cost (ACC), annual operating cost (AOC) and CO2 emission. The results show that the new heat-integrated extractive distillation configuration with [BMIM][OAC] as entrainer, known as EDHI-IL is the best solution for ecological efficiency. As compared to the CED process, TAC, ACC, AOC and CO2 emission of this process are reduced by 38.86%, 36.51%, 41.41% and 41.36%, respectively.

Applying a Deep Learning Network in Continuous Physiological Parameter Estimation Based on Photoplethysmography Sensor Signals

In this paper, we propose a continuous physiological parameter estimation model based on a deep learning network for photoplethysmography (PPG) sensor signals. Signals of 8-s duration were incorporated into the proposed model in this study for frequent estimation of the systolic blood pressure (BP), diastolic BP, heart rate (HR), and mean arterial pressure of the human body; this facilitated early identification and monitoring of physiological conditions and thus reduced the risk of cardiovascular disease. The proposed model was designed using a convolutional neural network (CNN) and long short-term memory (LSTM) network. This model was trained and validated using the large-scale Multiparameter Intelligent Monitoring in Intensive Care database. The CNN was used to extract features from PPG signals automatically. This automatic extraction replaced the conventional manual feature extraction process. Features with time-series were then analyzed using the LSTM network to estimate physiological parameters. Subsequently, ten-fold cross-validation was conducted to reveal the mean absolute errors ± standard deviations of participants’ systolic BP, diastolic BP, HR, and mean arterial pressure to be 2.54 ± 3.88, 1.59 ± 2.45, 1.62 ± 2.55, and 1.59 ± 2.34 mmHg, respectively. These values meet the standards established by the Association for the Advancement of Medical Instrumentation and the British Hypertension Society. The proposed method facilitates the accurate, continuous monitoring of the BP and HR.

Predicting Colorectal Cancer Using Residual Deep Learning with Nursing Care.

Presently, colorectal cancer is the second most dangerous cancer; around 13% of people have been affected; and it requires an effective image analysis and earlier cancer prediction (IAECP) system for reducing the mortality rate. Here, the IAECP system uses MRI radio imaging for predicting colorectal cancer. During this process, high- and low-level features are required to examine cancer in an earlier stage. Due to the limitation of the conventional feature extraction process, both features are difficult to extract from cancer suffered locations. Hence, a deep learning system (DLS) is used to examine the entire bowel MRI image to identify the cancer-affected location, feature extraction, and feature training process. Furthermore, the DLS-based IAECP system helps improve the overall colorectal cancer identification accuracy for further process. The derived bowel features are trained by applying the residual convolution network, which minimizes the error between predicted and actual values. Finally, the test query images are compared with the trained image by applying the sum, which is more absolute to the cross-correlation template feature matching (SACC) algorithm. The experimental process is performed using 100,000 histological data sets, which is considered a publicly available data set. Moreover, the introduced method does not use generic features, whereas the deep learning features help improve the overall IAECP prediction rate (99.8%) ratio as predicted at lab-scale analysis.

Lignin-Cellulose Nanocrystals from Hemp Hurd as Light-Coloured Ultraviolet (UV) Functional Filler for Enhanced Performance of Polyvinyl Alcohol Nanocomposite Films.

Lignin is a natural light-coloured ultraviolet (UV) absorber; however, conventional extraction processes usually darken its colour and could be detrimental to its UV-shielding ability. In this study, a sustainable way of fabricating lignin–cellulose nanocrystals (L-CNCs) from hemp hurd is proposed. A homogeneous morphology of the hemp particles was achieved by ball milling, and L-CNCs with high aspect ratio were obtained through mild acid hydrolysis on the ball-milled particles. The L-CNCs were used as filler in polyvinyl alcohol (PVA) film, which produced a light-coloured nanocomposite film with high UV-shielding ability and enhanced tensile properties: the absorption of UV at wavelength of 400 nm and transparency in the visible-light region at wavelength of 550 nm was 116 times and 70% higher than that of pure PVA, respectively. In addition to these advantages, the nanocomposite film showed a water vapour transmission property comparable with commercial food package film, indicating potential applications.

Towards sustainable separation of the ternary azeotropic mixture based on the intensified reactive-extractive distillation configurations and multi-objective particle swarm optimization

The separation of ternary azeotropic systems has received significant interest as it enables the recovery of value-added organic solvents, subsequently contribute towards environmental protection. In this work, we propose a novel approach that involves the conceptual design, multi-objective optimization, and process evaluations for developing two different processes, i.e., double-column reactive-extractive distillation (DCRED) and reactive-extractive dividing wall column (REDWC), for the separation of ethanol/tert-butanol/water ternary azeotropic mixture. The conceptual design of the proposed processes was conducted using kinetic and thermodynamic analysis while optimal operating conditions of the established processes were obtained via multi-objective particle swarm optimization algorithm. Then, both developed processes were evaluated based on the total annual cost (TAC), CO2 emissions, and thermodynamic efficiency. From the steady-state simulation, DCRED and REDWC provides a TAC of 1.056 × 106 US$ and 1.117 × 106 US$, respectively. Likewise, it provides CO2 emissions of 731.27 kg/h and 733.42 kg/h, respectively. The energy efficiency of the DCRED and REDWC were found to be 1.285% and 1.055%, respectively. Relative to the conventional extractive distillation process, the TAC and CO2 emission for the proposed DCRED reduced significantly by 55.4% and 61.8%, respectively. Similar reduction was also observed for the REDWC which provides 52.8% and 61.7% lower TAC and CO2 with respect to the conventional process. In addition, the thermodynamic efficiency of the developed DCRED and REDWC processes are improved by 40.4% and 15.3% in comparison to the conventional extractive distillation scheme.

Investigation on energy-efficient extractive distillation for the recovery of ethyl acetate and 1,4-dioxane from industrial effluent

Conventional extractive distillation processes have been proposed to separate the ternary ethyl acetate-1,4-dioxane-water system with azeotropes. Energy-efficient extractive thermally coupled processes with heat integration have been developed to reduce energy consumption. A macro-analysis of the energy, exergy, economy, and environment is conducted to estimate the economic and environmental benefits. The results proved that an extractive dividing-wall column with a heat-integrated process possessed the greatest energy-saving potential, delivered best economic performance and exhibited highest exergy efficiency. Compared to those of a conventional direct extractive distillation process, the total energy requirement and total annual investment cost are reduced by 28.18% and 24.28%, respectively, by the best energy-saving process. The total exergy efficiency of it is 1.779%. The proposed cleaner and sustainable extractive dividing-wall column configuration could achieve energy saving, investment reduction, and effectively enhance the exergy efficiency.

Currently Applied Extraction Processes for Secondary Metabolites from Lippia turbinata and Turnera diffusa and Future Perspectives

The poleo (Lippia turbinata Griseb.) and damiana (Turnera diffusa Wild) are two of the most valued species in the Mexican semidesert due to their medicinal uses. The conventional essential oil extraction process is hydrodistillation, and for the extraction of antioxidants, the use of organic solvents. However, these techniques are time-consuming and degrade thermolabile molecules, and the efficiency of the process is dependent on the affinity of the solvent for bioactive compounds. Likewise, they generate solvent residues such as methanol, hexane, petroleum ether, toluene, chloroform, etc. Therefore, in recent years, ecofriendly alternatives such as ohmic heating, microwaves, ultrasound, and supercritical fluids have been studied. These methodologies allow reducing the environmental impact and processing times, in addition to increasing yields at a lower cost. Currently, there is no up-to-date information that provides a description of the ecofriendly trends for the recovery process of essential oils and antioxidants from Lippia turbinata and Turnera diffusa. This review includes relevant information on the most recent advancements in these processes, including conditions and methodological foundation.

Integrated strategies for enzyme assisted extraction of bioactive molecules: A review

Conventional methods of extracting bioactive molecules are gradually losing pace due to their numerous disadvantages, such as product degradation, lower efficiency, and toxicity. Thus, in light of the rising demand for these bioactive, enzymes have garnered much attention for their efficiency in extraction. However, enzyme-assisted extraction is also plagued with a high capital cost that cannot justify the extraction yields obtained. In order to mitigate these problems, enzyme-assisted extraction can be consorted with non-conventional methods. This review includes current progress concerning the combined approaches while converging the recent advancements in the field that outperformed conventional extraction processes. It also highlights the design of biocatalyst and key parameters involved in the effective extraction of bioactive molecules. An integrated approach for efficiently extracting polyphenols, essential oils, pigments, and vitamins has been comprehensively reviewed. Furthermore, the different immobilization strategies have been discussed for large-scale implementation of enzymes for extraction. The integration of advanced non-conventional methods with enzyme-assisted extraction will open new avenues to enhance the overall extraction efficiency.

Optimal design and control of an energy-efficient triple-side-stream quaternary extractive distillation process

Dynamic control of extractive distillation process with multiple liquid side-streams is challenging although it has an energy-saving potential. In this work, the optimal design and control of a high-efficient triple-side-stream quaternary extractive distillation process (TSQED) is presented for separating acetone/methanol/butanone/tert‑butanol. All operating parameters are optimized by a simulated annealing based systematic method, resulting in the reduction of total annual costs by 9.37%, energy consumption by 18.76%, and CO2 emissions by 33.17% as compared with conventional extractive distillation process. Subsequently, three control structures (CS1, CS2, and CS3) are proposed and demonstrated according to different side-stream flowrate control strategy. In the CS1, the side-stream flowrate is proportional to feed flow. In the CS2, the side-stream flowrate is proportional to reboiler vapor flow. In the CS3, and temperature-sensitive plate in distillation column is identified and cascaded by side-stream flowrate. By contrast, CS3 is far better than CS1 and CS2 in terms of dynamic responses and integral performance criteria. This attributes to the virtuous effect of the inferential temperature control on side-stream flowrate in the whole process control of TSQED. Finally, the feedforward control of QR/F is added in the CS4 to further improve the effectiveness of CS3.

ULTRASOUND-ASSISTED EXTRACTION OF OLIVE OIL

The objective of this work was to perform a preliminary economic analysis of the ultrasound-assisted extraction process of olive oil and compare it with the manufacturing costs of the conventional extraction process. The DWSIM software was used for economic modeling considering data found in the literature; the five cost parameters were considered. The results showed a cost of USD 126.50/kg of olive oil in the proposed process. Although expensive, about 54,350 bottles more of oil could be produced due to the higher yield that can be obtained. In parallel, about USD 11,350,000.00 could be earned in one year of operation. In this sense, more research must be done to demonstrate the economic viability of this type of industry, to improve the operations and the costs of manufacturing until the process becomes profitable.

Production of lithium hydroxide by electrodialysis with bipolar membranes

• LiOH (2.2 M) and H 2 SO 4 (1.3 M) were successfully produced from Li 2 SO 4 (1.5 M). • The specific energy consumption was estimated to be around 7 kWh/kg LiOH produced. • The LiOH purity was improved to 99.75%, by limiting the H 2 SO 4 concentration in the acid compartment. • Battery grade LiOH may be possible after only a small reduction of the sulfate content. In conventional lithium extraction processes, highly purified lithium sulfate is generated as an intermediate, which is transformed into lithium hydroxide for lithium-ion battery applications. This study illustrates the technical feasibility of converting the pre-purified lithium sulfate (Li 2 SO 4 ) into lithium hydroxide (LiOH) and sulfuric acid (H 2 SO 4 ) using an electrodialysis with bipolar membrane (EDBM) process. A feed solution of 1.5 mol/L Li 2 SO 4 is converted into 2.2 mol/L LiOH and 1.3 mol/L H 2 SO 4 with a specific energy consumption of less than 10 kWh/kg LiOH produced. Due to the increased acid and base volume caused by electroosmosis, both acid and base concentrations are lower than that estimated based on stoichiometry. Increasing the initial LiOH solution concentration decreases the sulfate transfer from the acid and feed solutions to the base solution. Maintaining a low concentration of H 2 SO 4 in the acid compartment (0.05 mol/L) significantly reduces the migration flux of sulfate ions through the bipolar membrane, leading to a LiOH purity of ~99.75%. This also lowers the energy consumption to ~7 kWh/kg, with a reduced average sulfate leakage flux into the base solution (~0.008 mol/m 2 hr). Battery grade LiOH could be obtained after a small further reduction of the sulfate content. This work demonstrates that EDBM can potentially replace the current chemical precipitation technique to produce LiOH from Li 2 SO 4 , by eliminating the use of a large quantity of alkali and the associated precipitation and solid–liquid separation steps.

Extraction and Characterization of the Polar Lipid Fraction of Blackberry and Passion Fruit Seeds Oils Using Supercritical Fluid Extraction

The study of the phytochemical composition of seed oils is of upmost importance for the food and cosmetic industries, mainly considering their associated biological properties. Extraction of seed oils using supercritical fluids (SFE) is an ecological and green alternative to conventional extraction processes since it is able to provide with potent bioactive extracts, avoiding degradation and transformation of the compounds present originally in the raw material. The objective of the present work was the extraction of pure fractions of polar lipids and their chemical characterization using chromatographic techniques such as GC-MS and LC-DAD-MS/MS of blackberry (Rubus glaucus) and passion fruit (Passiflora edulis) seed oils extracted by supercritical carbon dioxide. Oleamides derived from oleic acid were identified as the main compounds in both samples; in particular, 9-octadecenamide was the major identified oleamide. Besides, the extract obtained from passion fruit showed to be a source of linoleic acid, while the SFE extract from blackberry presented important concentrations of vanillin. The chemical composition of these seed oils can be of high interest for their further use in cosmetics and food industry.

Bioleaching of vanadium by Acidithiobacillus ferrooxidans from vanadium-bearing resources: Performance and mechanisms

Bioleaching is promising to meet the demand of strategic vanadium both economically and environmentally. Whereas the combination of bioleaching with traditional techniques is of great interest, little is known on bioleaching of vanadium from abundant vanadium-bearing resources utilized/produced in existing processes. This study investigated the bioleaching of vanadium from vanadium-titanium magnetite, steel slag, and clinker, which are common raw mineral and intermediates used in conventional vanadium extraction process. Clinker had greater leachability by Acidithiobacillus ferrooxidans, compared to vanadium-titanium magnetite and steel slag. Pulp density, inoculum volume, initial pH and initial Fe2+ concentration had influencing effects on this bioleaching process. Under optimal condition with 3% pulp density, 10% inoculum volume, initial pH at 1.8, and 3 g/L initial Fe2+ concentration, the bioleaching of clinker achieved the maximum vanadium leaching efficiency of 59.0%. Both X-ray fluorescence and energy dispersive spectroscopy analysis confirmed the reduction of vanadium content in the solid residues after leaching. The results of Community Bureau of Reference sequential extraction suggested that vanadium in acid-soluble and oxidizable phase was more easily leachable. This study is helpful to develop sustainable and practical techniques for vanadium extraction from abundant raw materials and step forward in combining bioleaching with traditional process.

Pollution Free and Sustainable Copper Production Using Greenhouse Gas CO2

The objectives of the present investigation to decrease the global pollution by utilizing the CO2 gas, in an effective way to produce the valuable metal copper, using low grade Cu ore which is termed as waste and not used for conventional Cu production. So the idea being waste and polluting waste are converted to useful products which will create employment, boost economy and reduce environment pollution. It is an innovative scheme for start-up. Carbonic acid produced by dissolving greenhouse gas CO2 was used for leaching low grade chalcopyrite ore under oxidizing condition. It is a single stage process with a single reactor where combined hydrometallurgical and electrometallurgical process occur. At anode an oxidizing condition is produced by dragging electron thereby increasing the rate of hydrometallurgical extraction producing Cu++ from CuFeS2. This generated Cu++ is simultaneously deposited at the cathode in the same reactor. The Cu produced was analysed and identified by RDR. The electrical power and energy consumption were computed. In the conventional cu extraction process from CuFeS2, sulphur come out as SO2 , the harmful polluting gas, in contrast in this process, sulphur came out as elemental sulphur and can be sold as by-product.

Microwave-assisted extraction of pectin from pineapple peel

Pineapple peel has the potential to become one of the sources for pectin production due to the high content of pectin in its dietary fibre composition. Pectin is used as food thickener, emulsifier, stabiliser and gelling agent in food industry. The conventional extraction process with long operating hours at high temperature has been identified to cause thermal degradation of pectin molecules. Microwave technology application in pectin extraction has shown high potential to expedite the extraction process and produce higher yield. Therefore, this research was intended to investigate the effect of various factors (irradiation time, pH, temperature, microwave power and solid-to-solvent (S/S) ratio) of microwave-assisted extraction (MAE) on the pineapple peel pectin (PPP) yield. Pectin extracted was then analysed for its dry weight yield percentage and degree of esterification (DE). It was shown that the pectin yield was significantly affected by pH, S/S ratio and microwave power. From this study, no significant effect of irradiation time was observed from 2.5 min until 20 min to the yield of pectin, thus longer time of extraction is not necessary in MAE. The highest yield of PPP obtained was in the range of 2.27 to 2.79% w/w at pH 2.0 and S/S ratio of 1:20. The result of DE (63.93 ± 0.30%) indicated that PPP is categorized in high methoxyl pectin (HMP) pectin type because the DE values were greater than 50%. This study showed that MAE is highly potential for extraction of high yield of PPP.

Performance comparison of microwave cavities used for extraction operations

AbstractIn the agri-food industry world, billions of tons of waste are produced every year. This represents both a direct loss (due to the failure to exploit their potential value, and their nutritional and energy content) and indirect loss, due to their necessary treatment and/or disposal. Some substances contained in the wastes, of potential high value, can be recovered by means of extraction. Conventional extraction processes involve the use of solvents, which end up requiring an additional process of separation from the solute identified as the desired product. In recent years, extraction techniques have been proposed without the use of solvents. This work compares the performance of two microwave cavities used for extraction operations, both working at 2.45 GHz.A calorimetric analysis performed by following the heating rate and temperature evolution in rack of 25 beakers filled with 25 mL of water, coupled with the solution of the heat transfer balance in the system, allowed to build the spatial distribution of the electromagnetic power dissipated as heat in each of the beakers. Fluid-dynamics aspects related to the recovery of the vapour phase produced during the extraction were also analyzed, with particular emphasis on the mean residence time of the vapour fraction in the extraction chamber as a function of its configuration.

Optimization Extraction of Indigofera tinctoria L. using Microwave-assisted Extraction

Dyes are many used in textiles, food, drink, and cosmetics. In the textile industry, the demand for dye is increasing, especially in natural dye. One of the natural dye that is often used in those products is Indigofera tinctoria L. due to its various potential. However, the time extraction needed is very long in the conventional extraction process. Because of that, some researchers have proved that microwave-assisted extraction takes a short time and high yield extraction obtained because microwave radiation is transmitted to the plant matrix that increasing solubility of solvent, and decreasing surface tension. Correlated with that, Indigofera tinctoria L. dye extraction using microwave-assisted extraction has been analyzed by modeling with response surface methodology with Box-Behnken Design (BBD) with parameters of ratio feed to solvent (0.02-0.1 g/ml), temperature (50-60°C) and extraction time (50-90 minutes). The obtained model could represent the extraction process and showed there an interaction among parameters on the yield, but ratio F/S had the most significant effect. Besides, the difference of optimization model obtained at optimum condition process extraction at ratio feed to solvent 0.02, temperature 60°C, and 50 minutes. The actual yield is 4.976% is closed to the predicted yield which the value is 4.85%. The compounds and similarity of the sample were analyzed using FT-IR and the similarity compound of indigo is 39.11%.

Pengaruh Amplitudo Ultrasonik dan Waktu Ekstraksi Terhadap Rendemen dan Mutu Oleoresin Pala

Nutmeg oleoresin is one of the nutmeg derivative products with high values produced from the extraction process. The conventional extraction process using maceration takes a long time so that it is less suitable for industries needs. This study aims to examine the UAE direct sonication method for increasing yield and quality of nutmeg eleoresin. Nutmeg with optimal maturity level were harvested, dried and milled into 60 mesh particle size. Nutmeg powder of 200 g was placed in beaker glass filled with etanol 800 ml (material and solvent ratio 1:4) and UAE was carried out using a sonicator with a frequency of 20 kHz and power of 700 W. Four ultrasound amplitude levels (45, 60, 75, 90%) and four levels of extraction time (30, 45, 60, 75 minutes) were taken as UAE treatments. Extraction using maceration at room temperature for 7 hours was done as control. The results showed that the greater the amplitude of the ultrasound, the higher the yield of nutmeg oleoresin. The longer the extraction time, the higher the yield of nutmeg oleoresin. Ultrasonic assisted extraction can increase nutmeg oleoresin yield by 11 to 52% and faster time (<= 1,25 hour) than maceration extraction method (7 hours).