Search results for "Distillation"
showing 10 items of 184 documents
Citrus somatic hybrid leaf essential oil
2000
The essential oil from the leaves of a Citrus interspecific somatic hybrid obtained by symmetric protoplast fusion between ‘Milam’ lemon [purported sexual hybrid of C. Jambhiri Lush (×) C. sinensis] and ‘Femminello’ lemon (C. limon L. Burm f.) has been characterized by steam distillation GC–MS analysis and its composition compared with that of the corresponding oils obtained from the parent plants. The amount (%) of the different classes of substances present in the oils show, in the new hybrid, an overall lowering of the hydrocarbon fraction and an increase of the oxygenated components. The somatic hybrid shows a close similarity in the amounts of terpenes, sesquiterpenes and alcohols with…
Composition of the essential oil fromflowerheads ofChrysanthemum coronarium L.(Asteraceae) growing wild in Southern Italy
2004
The essential oils from the aerial parts of Chrysanthemum coronarium L. (Asteraceae) growing wild in two different localities of Southern Italy, Lascari (L) and Palinuro (P), were obtained by hydrodistillation in a 0.13-0.16% yield. The oils were analysed by GC and GC-MS; 68 constituents, amounting to 89.0% of the oil (L), and 43 constituents, amounting to 91.6% of the oil (P), were identified. The trans-spiroketal-enol ether 2-(2,4- hexadiynylidene)-1,6-dioxaspiro(4,4)non-3-ene (trans-tonghaosu) with chrysanthenyl and lyratyl esters and camphor were the main components of the oils. Copyright © 2004 John Wiley & Sons, Ltd.
Chemical composition of the essential oils fromEriocephalus africanus L. var.africanus populations growing in Spain
2007
Essential oils from the aerial parts of three Eriocephalus africanus L. var. africanus populations were analysed by means of GC–FID and GC–MS. Sixty-one constituents were identified, representing more than 96% of the total oil composition. Artemisia ketone (56.46–56.58%), intermedeol (9.19–11.63%) and γ-eudesmol (4.26–5.64%) were the main compounds. Application of the Pearson correlation coefficient showed high similarity between the nine samples analysed. Copyright © 2007 John Wiley & Sons, Ltd.
Composition of the essential oil ofPallenis spinosa (L.) Cass. (Asteraceae)
2003
The essential oil of Pallenis spinosa (L.) Cass. was obtained by hydrodistillation. In total 38 components were identified by GC and GC–MS. Oxygenated sesquiterpenoids amounted to 60.2% of the oil. The main components were germacra-1(10),5-dien-3,4-diol (18.4%), α-cadinol (14.1%), 3-acetoxygermacra-1(10),5-dien-4-ol (13.0%), T-cadinol (8.2%) and δ-cadinene (5.8%). The oil does not show antimicrobial activity. Copyright © 2003 John Wiley & Sons, Ltd.
Application of solar energy to seawater desalination in a pilot system based on vacuum multi-effect membrane distillation
2020
Abstract The evaluation of a novel solar seawater desalination system implemented at the University of Almeria (Spain) is presented. It integrates a solar thermal field based on static collectors and a thermal desalination system based on the vacuum multi-effect membrane distillation technology. The distillation unit has a particular innovation to increase its thermal performance, using a seawater flow to condense the steam and preheat the feed. Experiments were made under different environmental conditions to assess the role of the thermal storage system for minimizing the effect of disturbances in solar radiation. Thermal energy could be delivered at a stable temperature to the distillati…
Assessment of a pilot system for seawater desalination based on vacuum multi-effect membrane distillation with enhanced heat recovery
2018
Abstract This work presents the evaluation of an innovative system based on vacuum multi-effect membrane distillation modules (V-MEMD) for seawater desalination at pilot scale. This four-effect unit introduces a remarkable modification from previous V-MEMD systems, consisting of the use of the seawater feed flow as cooling in the condenser, rather than a separate circuit. Preheating the feed in the condenser improved heat efficiency (maximum gained output ratio obtained for seawater was 3.2). Maximum distillate fluxes reached 8.5 l h−1 m−2 for hot feed temperature 75 °C and feed flow rate 150 l h−1. Increasing both parameters to raise the productivity was hindered by the inability of the co…
Chemical composition and antimicrobial activity of the essential oil ofPhlomis ferruginea Ten. (Lamiaceae) growing wild in Southern Italy
2006
The essential oil of aerial parts of Phlomis ferruginea (Lamiaceae), growing wild in Southern Italy, was obtained by hydrodistillation and analysed by GC and GC–MS. 60 compounds, representing 92.3% of the oil, were identified. The major components were β-caryophyllene (15.6%), hexadecanoic acid (12.8%), germacrene D (8.9%), caryophyllene oxide (6.7%) and α-thujone (5.5%). The evaluation of antimicrobial activity against some bacterial species has been tested. Copyright © 2006 John Wiley & Sons, Ltd.
Microwave-assisted distillation of iodine for the indirect atomic absorption spectrometric determination of iodide in milk samples
2001
To complete these microwave distillation studies, a method for iodide determination in milk-type samples is proposed. The iodide contained in the sample is oxidized to iodine, which is distilled by means of microwave energy and reduced back to iodide. This iodide is combined with Hg(II) and 2,2′-dipyridyl to give an ion pair, which is selectively extracted into IBMK. Mercury is determined in the extract by ETAAS in order to determine iodide. The yield of the distillation process (100%) was evaluated using the Sandell–Kolthoff reaction. In addition, for the solvent extraction, no buffer was needed; 3/5 was the best phase ratio (organic/aqueous); 30 s was the shaking time and the extracts wer…
Separation of isobutyl alcohol and isobutyl acetate by extractive distillation and pressure-swing distillation: Simulation and optimization
2006
Abstract We have studied, simulated and evaluated economically two separation alternatives of a mixture made up of 52 mole% of isobutyl alcohol and 48 mole% of isobutyl acetate by means of a practical case of a plant to treat 12,000 Tm/year of the original mixture. The simulation has been carried out satisfactorily by means of a package of commercial software (Aspen HYSYS ® ) using the thermodynamic model UNIQUAC with binary parameters obtained experimentally by us. The two processes evaluated (extractive distillation using n -butyl propionate as a solvent and pressure-swing distillation) have been optimized independently from each other and the best configurations have been evaluated econo…
γ-Oryzanol and tocopherol contents in residues of rice bran oil refining
2012
Rice bran oil (RBO) contains significant amounts of the natural antioxidants γ-oryzanol and tocopherols, which are lost to a large degree during oil refining. This results in a number of industrial residues with high contents of these phytochemicals. With the aim of supporting the development of profitable industrial procedures for γ-oryzanol and tocopherol recovery, the contents of these phytochemicals in all the residues produced during RBO refining were evaluated. The samples included residues from the degumming, soap precipitation, bleaching earth filtering, dewaxing and deodorisation distillation steps. The highest phytochemical concentrations were found in the precipitated soap for γ-…