total extraction
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2021 ◽  
Vol 5 (1) ◽  
pp. 85
Author(s):  
Aikaterini Toli ◽  
Georgia Maria Tsaousi ◽  
Efthymios Balomenos ◽  
Dimitrios Panias ◽  
Matthias Heuer ◽  
...  

Calcium aluminate slag produced by the aluminothermic reduction of silica is tested as a candidate raw material for the hydrometallurgical production of pure aluminium chloride hexahydrate (ACH) through leaching with hydrochloric acid. The crystallization of ACH follows by sparging the pregnant liquor with hydrochloric gas. Almost total extraction of Al is achieved with the use of azeotropic HCl acid solution (5.9 M) at 80 °C and 1 h retention time. A pregnant liquor with approximately 20 wt% AlCl3 is produced as a base for ACH crystallization by sparging it with gaseous HCl. The ACH produced is re-dissolved and crystallized three to four times until high purity is achieved. High purity ACH acts as a precursor for producing High Purity Alumina (HPA), a high added value material used in LEDs and lithium-ion batteries and other niche applications.


Beverages ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 63 ◽  
Author(s):  
Achillia Lakka ◽  
Eleni Bozinou ◽  
Giorgos Stavropoulos ◽  
Iordanis Samanidis ◽  
Vassilis Athanasiadis ◽  
...  

The current study evaluates the Pulsed Electric Field (PEF) technique for the extraction of polyphenols from the plants Rosa canina, Calendulaofficinalis and Castanea sativa. These plants are traditionally used both for the preparation of therapeutic decoctions and the aromatization of beverages (alcoholic or not). Pulses of 10 μs duration were used to apply electric field intensities ranging from 1.2 to 2.0 kV cm−1. The period of the phenomenon was set to 1 ms, with a total extraction time of 20 min. The total polyphenol content as well as the identified polyphenolic compounds of the extracts were determined for monitoring and evaluation. To estimate the PEF effect, control extracts were prepared using the same process as PEF extracts but without the application of electric field. For all the three plant materials studied, the PEF technique appeared to be successful in increasing polyphenols extraction. The application of a moderate to high electric field, up to 1.4 kV cm−1, resulted in increased total and individual polyphenols recovery, reaching 63.79% and 84%, respectively, in the case of Rosa canina fruits.


Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1159
Author(s):  
Vítor H. Rodrigues ◽  
Marcelo M. R. de Melo ◽  
Inês Portugal ◽  
Carlos M. Silva

Forestry biomass is a by-product which commonly ends up being burnt for energy generation, despite comprising valuable bioactive compounds with valorisation potential. Leaves of Acacia dealbata were extracted for the first time by supercritical fluid extraction (SFE) using different conditions of pressure, temperature and cosolvents. Total extraction yield, individual triterpenoids extraction yields and concentrations were assessed and contrasted with Soxhlet extractions using solvents of distinct polarity. The extracts were characterized by gas chromatography coupled to mass spectrometry (GC-MS) and target triterpenoids were quantified. The total extraction yields ranged from 1.76 to 11.58 wt.% and the major compounds identified were fatty acids, polyols, and, from the triterpenoids family, lupenone, α-amyrin and β-amyrin. SFE was selective to lupenone, with higher individual yields (2139–3512 mg kgleaves−1) and concentrations (10.1–12.4 wt.%) in comparison to Soxhlet extractions, which in turn obtained higher yields and concentrations of the remaining triterpenoids.


Author(s):  
Maimaiti Aisha ◽  
Atikanmu Wahafu ◽  
Yilifanjiang Kuerban ◽  
Akenmujiang Aierken ◽  
Refuhati Saimaiti ◽  
...  

Objective: To establish the decocting and formulation technology of Saifula granules, and establish a reliable TLC identification quality control standard. Methods: Orthogonal test was used to optimize the water extraction process and TLC was used for qualitative identification. Results: To optimize the process parameters of SFL granules, first, the content of total flavonoids and the total extraction rate were taken as the indexes. Through single factor and orthogonal test, the optimal extraction process was determined as follows: extraction time 1 h, solvent multiple 1:10, extract three times. After the process parameters were determined, in order to further explain the chemical composition of SFL extract, 15 compounds in SFL extract were identified by UHPLC-Q-Orbitrap-MS, 13 batches of SFL extracts were prepared, and their fingerprints were analyzed. The results showed that there were 28 common characteristic peaks in the 13 batches of SFL extracts. The similarity evaluation results of fingerprints showed that the similarities of 13 batches of SFL extracts were greater than 0.9. An HPLC-DAD method for the simultaneous determination of gallic acid, corilagin, and ellagic acid was established. The method has good repeatability, stability, and accurate results. Conclusion: The standard can comprehensively reflect the material basis of SFL granules, and the above methods are accurate, easy to operate, stable and feasible, and provide scientific basis and basis for the development, promotion, and clinical application of SFL granules.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1826
Author(s):  
Alessandro Coroli ◽  
Roberta Romano ◽  
Andrea Saccani ◽  
Noura Raddadi ◽  
Elisa Mele ◽  
...  

Lactobionic acid (LBA) is widely used in different industrial sectors owing to its biocompatibility characteristics as well as antioxidant and antimicrobial properties. In this study, mixtures of the protein zein with LBA and with the addition of oleic acid (OA) as a ternary system were investigated as drug delivery films for the release of LBA. The chosen combinations exploit the vast difference in water solubility between LBA and the other two components (zein and OA). DSC thermograms and dynamic mechanical spectra, alongside electron microscopy images, were used to describe the microstructural features of the films and were found to provide insights for the release of LBA from the two examined zein-based films immersed in an aqueous physiological solution. For both film systems, a burst release behavior was observed, followed by a rapid and total extraction of LBA. The required immersion time for the total extraction of LBA was greatly reduced when oleic acid was added to the precursor solution mixture for producing the films. The LBA released from the zein-based films was found to exhibit both the expected antioxidant properties as well as exerting bacteriostatic effects towards Escherichia coli and Staphylococcus epidermidis.


2020 ◽  
Vol 13 (10) ◽  
pp. 301
Author(s):  
Yesica Vicente-Martínez ◽  
Manuel Caravaca ◽  
Antonio Soto-Meca

Bisphenol A (BPA) is a chemical compound used in the manufacturing of plastics and resins whose presence in the body in low concentrations can cause serious health problems. Due to this, there is a growing interest in the scientific community to develop analytical methods that allow quantifying trace concentrations of BPA in different types of samples. The determination of this compound in toys made of plastics that can be manipulated by children leads to an extra concern, because it is possible for BPA to enter the body by introducing these toys into the mouth. This work presents a novel procedure to the quickly and easily quantification of trace levels of BPA in samples of toys and pacifiers according to the current demanding regulations. The determination of very low levels of BPA was carried out by ionic liquid dispersive liquid–liquid microextraction (IL-DLLME) followed by high-performance liquid chromatography (HPLC). The formation in situ of the ionic liquid (IL) 1-octyl-3-methylimidazolium bis((trifluoromethane)sulfonyl)imide ([C8MIm] [NTf2]), was achieved by mixing 1-octyl-3-methylimidazolium chloride ([C8MIm]Cl) and lithium bis(trifluoromethanesulfonyl)imide ([NTf2]Li) aqueous solutions, reaching an instant dispersion whose cloud of microdrops allows the total extraction of BPA in the IL from aqueous solutions. After centrifugation, BPA concentration in the sedimented phase was determined by HPLC. The optimal experimental conditions for the microextraction and determination of BPA in the IL were studied. The total extraction was achieved at pH 4, heating the sample at 30 °C for 5 min, using 100 µL of IL precursor volume, and spinning after the formation of dispersion at 3000 rpm for 10 min. The enrichment factor (EF) and detection limit (LOD) reached with the procedure were 299 and 0.19 µg L−1, respectively. The relative standard deviation for ten replications at the 0.5 µg L−1 level was 5.2%. Recovery studies showed a mean value for BPA recovery percentage in the samples of 99%. Additionally, a hybrid model was applied to characterize the extraction kinetics. This simple, low cost and fast method simplifies traditional microextraction techniques, representing an outstanding alternative.


Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4107
Author(s):  
André Vervoort

Since the 1990s, remote sensing data have been available to monitor the surface movement for long periods of time. The analysis of satellite data shows that there is still residual subsidence (i.e., with average rates of about −10 mm/year) several decades after mining longwall panels in an area. Several years after the underground infrastructure was sealed, the surface started to move upwards. In the past, it often was claimed that movement of the surface was limited in time, i.e., a few years after mining a longwall panel. This is not the case for the conditions of the Campine coal basin, Belgium. This knowledge is important when one wants to design new operations in deep coal seams, but also when planning to stop the underground mining and to seal the access to the mine.


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