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Study on the degreasing of sheepskin by subcritical CH2Cl2 / Shanshan Yu in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 105, N° 2 (03-04/2021)
[article]
Titre : Study on the degreasing of sheepskin by subcritical CH2Cl2 Type de document : texte imprimé Auteurs : Shanshan Yu, Auteur ; Yingxuan Wang, Auteur ; Meina Zhang, Auteur ; Hong Dai, Auteur ; Qiang Liu, Auteur ; Zongcai Zhang, Auteur Année de publication : 2021 Article en page(s) : p. 72-76 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Dégraissage
Cuirs et peaux de moutons
DichlorométhaneLe dichlorométhane (DCM) ou chlorure de méthylène (dénommé R30 dans la liste des gaz fluorés et frigorigènes), est un composé chimique se présentant à température ambiante comme un liquide incolore et volatil émettant une odeur douceâtre relativement forte pouvant mettre certaines personnes mal à l'aise. Son odeur est perceptible dès 200–300 ppm (dès 25 ppm ou seulement vers 600 ppm selon d'autres sources).
Il est surtout utilisé comme solvant de composés organiques.
Caractéristiques chimiques : Caractéristiques chimiques
- Il est peu soluble dans l'eau (13 à 20 g·l-1 à 20 °C) ;
- Il est miscible avec la plupart des solvants organiques ;
- Solvant efficace sur de nombreux produits organiques (graisses, huiles, résines, etc.).
- Il réagit violemment (explosion possible en présence de certains catalyseurs courants ou d'autres solvants chlorés) avec des poudres métalliques (aluminium, magnésium), et réagit spontanément et fortement avec les métaux alcalins, les bases fortes et les oxydants puissants.
Extraction par solvant
TempératureIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : In this paper, subcritical CH2Cl2 solvent was applied to the degreasing process of sheepskin. The optimal process parameters of degreasing were determined by single factor experiment and the degreasing efficiency was evaluated by the degreasing rate. The effect of degreasing temperature on the connection between hair and hair follicle, fat content of lipid cells and the fibre dispersion of the sheepskin were investigated through the use of optical microscope and the scanning electron microscope. The single experiments results showed that when the moisture content of the raw skin was about 60%, degreasing time was 50 minutes, degreasing temperature 39°C, and degreasing pressure 0.5MPa and the solid liquid ratio was 1:7. The degreasing rate of sheepskin with the subcritical CH2Cl2 extraction was 52%. The results of histological observation and scanning electron microscopy showed that the connection between the hair and the hair follicle is weakened and the lipid cells have a relatively low lipid content with increasing temperature. However; the fibres were well dispersed when the degreasing temperature was higher than 41°C, therefore, the most suitable degreasing temperature would be about 40°C. Compared with the traditional degreasing methods, subcritical CH2Cl2 extraction has the characteristics of clean and environmental protection, good fibre dispersion and good bond between hair and hair follicle. Note de contenu : - MATERIALS AND METHODS : Experimental instruments and materials - Sample preparation - Optimisation of subcritical CH2Cl2 extraction variables for degreasing process - Effect of degreasing temperature on the connection between hair and hair follicle - Effect of degreasing temperatures on the fibre dispersion
- RESULTS AND DISCUSSION : Optimisation of degreasing process parameters - Effect of degreasing temperature on the connection betweenhair and hair follicle - Effect of degreasing temperature on dispersion of skin fibre
- Table 1 : Single-factor experiment design tableEn ligne : https://drive.google.com/file/d/13j7hoPwqKJt0tMrSRGNajc9BUT6TLBMo/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=35543
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 105, N° 2 (03-04/2021) . - p. 72-76[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 22651 - Périodique Bibliothèque principale Documentaires Disponible The rise of deep eutectics from nature to cosmetics / Mickael Laguerre in PERSONAL CARE EUROPE, Vol. 9, N° 1 (02/2016)
[article]
Titre : The rise of deep eutectics from nature to cosmetics Type de document : texte imprimé Auteurs : Mickael Laguerre, Auteur ; Alexis Lavaud, Auteur Année de publication : 2016 Article en page(s) : p. 45-47 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Développement durable
EutectiquesUn eutectique est un mélange de deux corps purs qui fond et se solidifie à température constante, contrairement aux mélanges habituels. Il se comporte en fait comme un corps pur du point de vue de la fusion.
C'est aussi le point du diagramme (mélange avec une proportion donnée) pour lequel le mélange est à sa température minimale en phase liquide. Cette température est propre à chaque mélange.
Extraction par solvant
Ressources renouvelables
Solvants écologiquesIndex. décimale : 668.5 Parfums et cosmétiques Résumé : Deep eutectic solvents probably evolved very early in the history of living organisms and may reflect a fundamental component of the chemistry of life. Scientists are now rediscovering all kinds of molecule combinations engineered by nature into these unique mixtures. Harnessing these bio-inspired solvents for eco-extraction purposes is one of the most exciting ways to recover phytoactive molecules using the same strategy adopted by plants for their survival.
The depletion of fossil resources, combined with changes in the regulatory, environmental and toxicological frameworks for solvents, puts heavy selective pressure on the development of alternatives to petro-based organic solvents. Finding sustainable and eco-friendly extraction technologies capable of producing extracts with novel phytochemical profiles and enhanced efficacy has become increasingly important.Note de contenu : - Andrew Abbott's discovery of a new type of solvents
- Do plant cells contain liquids other than water and lipids ?
- Deep eutectic solvents : a game-changer in botanical extractionEn ligne : https://drive.google.com/file/d/1amWm7VNw5SrICTGTRuT67Lw9dqe-3UJo/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=25619
in PERSONAL CARE EUROPE > Vol. 9, N° 1 (02/2016) . - p. 45-47[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 17835 - Périodique Bibliothèque principale Documentaires Disponible Ultrasound assisted vegetable tannin extraction from myrobalan nuts for leather application / Venkatasubramanian Sivakumar in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXIII, N° 2 (02/2018)
[article]
Titre : Ultrasound assisted vegetable tannin extraction from myrobalan nuts for leather application Type de document : texte imprimé Auteurs : Venkatasubramanian Sivakumar, Auteur ; A. Princess, Auteur ; C. Veena ; R. Lakshmi Devi Année de publication : 2018 Article en page(s) : p. 53-58 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Eau
Essais (technologie)
Extraction par solvant
Extraction par ultrasons
Myrobalan et constituants
Tanins végétaux
Tannage végétal -- AnalyseIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Ultrasound (US) assisted preparation of tannins from Terminalia Chebula nuts (myrobalan) through solid-liquid extraction process using water as solvent even dispensing with conventional heating/stirring is presented in this paper. The results indicate there is a significant enhancement in myrobalan extraction due to the influence of US, in extract %yield and tannin contents respectively as compared to different control processes (static/stirring). Whereas, ultrasound probe at 120 W in 50°C water bath gave the best overall %yield and tanning content. Some of the important scale-up parameters could be a significant savings of 427,184 and 188 kg per ton of raw material usage as extrapolated values based on Lab-scale results in terms of % yield, tannin content and tanning agent offer respectively due to the use of US as compared to control process. The process involves : i). Clean technology with physical activation (US) in aqueous medium at ambient condition - no additional chemicals ii). Green and Eco-benign process with natural materials - useful in all extract applications, iii. Tannins extract as generic product for better functional properties, iv). Better diffusion of plant extract through skin matrix in tanning process for leather making, v). Sustainable solution and ecoconservation through better yields Note de contenu : - EXPERIMENTAL : Experimental Set up - Experimental Procedure - Tanning Trials - Analytical methods - Quantitative analysis of tannin content
- RESULTS AND DISCUSSIONS : Myrobalan extraction in ultrasonic tank - Effect of extraction in US probe - Effect of US power, temperature and stirring in extration - Enhancement factors for myrobalan extraction with ultrasound - Effect of distance of material from US probe tip - Mechanism tor the ultrasound assisted extraction - Two-stage extraction - Efficacy of extract in tanning process - Experimental results and process scale-up considerationsEn ligne : https://drive.google.com/file/d/1Nfgs9Mp-HnCkG6Q4zlf4t-oXsI-oBK3b/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=29951
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXIII, N° 2 (02/2018) . - p. 53-58[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 19539 - Périodique Bibliothèque principale Documentaires Disponible Value added leather auxiliaries from paper and pulp industry waste / Mohan Vedhanayagam in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CX, N° 9 (09/2015)
[article]
Titre : Value added leather auxiliaries from paper and pulp industry waste Type de document : texte imprimé Auteurs : Mohan Vedhanayagam, Auteur ; Tewodros Kassa, Auteur ; Kalarical Janardhanan Sreeram, Auteur ; Jonnalagadda Raghava Rao, Auteur ; Balachandran Unni Nair, Auteur Année de publication : 2015 Article en page(s) : p. 295-301 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Agents de tannage
Extraction par solvant
Formaldéhyde
Liqueur noire -- RecyclageLa liqueur noire est la liqueur de cuisson issue de la fabrication du papier kraft. Il s'agit d'une solution aqueuse composée des résidus de lignine et d'hémicellulose dissous de la pâte à papier, ainsi que des autres composés chimiques inorganiques utilisés dans le processus de dissolution. Elle contient en outre plus de la moitié de la teneur énergétique du bois amené dans le lessiveur. Normalement concentrée jusqu'à 65 % - 80 % par un évaporateur multi-effets, elle est ensuite brûlée à 1 200°C dans une chaudière de récupération afin de produire de l'énergie et récupérer les produits chimiques de cuisson.
Papèterie -- Déchets -- Recyclage
Récupération (Déchets, etc.)
SulfonationIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : The present work involves the preparation of a retanning agent from the organics present in the black liquor generated by paper and pulp industry. Black liquor organics was extracted by using solvent extraction method and subsequently separated as acidic, non-acidic and organic compounds that were not degraded. Acidic and non acidic organics were sulfonated and further condensed with formaldehyde to obtain a product ideal for application. Sulfonation – condensation reactions were modulated to achieve particle size on par with that of commercial syntans. Condensed products from both acidic and non-acidic components were used in lieu of synthetic tanning agents in retanning. The final leathers exhibit offwhite color with good mechanical strength as compared to leathers from commercial phenolic syntan. This work reveals that the black liquor, which is a by-product of paper and pulp industry could through an innovative process, be turned into a retanning agent for leather processing. The product has the advantage of being able to replace phenol – a product with high market fluctuation. Note de contenu : - EXPERIMENTAL : Materials and methods - Extraction of acidic and non-acidic organics from black liquor - Preparation of syntan from non-acidic organics of black liquor (Syntan A) - Preparation of syntan from acidic organics (Syntan B) - FT-IR spectroscopy - Dynamic light scattering (DLS) - Performance evaluation on leather - Determination of color difference of crust leathers - Physical testing of crust leathers - Evaluation of organoleptic properties - Optical microscopic analysis - Formaldehyde content in the leather - Gas-permeability analysis
- RESULTS AND DISCUSSION : Extraction of degraded lignin - FT-IR spectrum of organic and non-acidic organic components - Particle size of condensed product - Color measurements - Performance evaluation of developed syntans. 1. Evaluation of organoleptic properties - Evaluation of crust leather - II. Gas permeability analysis - Overall considerationsEn ligne : https://drive.google.com/file/d/1wry6s1S2NwzB3pqkvelQnrvmrMVgS7Ex/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24597
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CX, N° 9 (09/2015) . - p. 295-301[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 17423 - Périodique Bibliothèque principale Documentaires Disponible