The enzyme activity of trypsen on sheepskin trimmings in a two-step collagen extraction process / F. Fernandez-Hervas in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CII, N° 1 (01/2007)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CII, N° 1 (01/2007) . - p. 1-9 Titre : The enzyme activity of trypsen on sheepskin trimmings in a two-step collagen extraction process Type de document : texte imprimé Auteurs : F. Fernandez-Hervas, Auteur ; Albert M. Manich, Auteur ; Agusti Marsal, Auteur ; Jaime Cot, Auteur ; J. Cisa, Auteur ; I. Punti, Auteur ; Pedro J. Celma, Auteur Année de publication : 2007 Article en page(s) : p. 1-9 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The extraction of collagen from raw sheepskin trimmings was studied in a two-step process. In the first step trypsin was used to perform an enzyme digestion. Subsequently, an extraction was carried out with a 0.5 molar acetic acid solution. The temperature, pH and enzyme concentration were varied in the enzyme digestion step and their influence on this step’s extract was examined. Conditions in the second step were kept constant in order to assess the influence of first step variables on the overall process. In all cases, the evolution of the response was analyzed as a function of digestion time. The main findings were the following: there was low enzyme activity in the first hour of digestion and initial pH had a significant influence on the overall process. A 5.8 percent yield of collagen was extracted with respect to the dry skin. This yield was limited by the second step. En ligne : https://drive.google.com/file/d/1025QhLyFFE0aUcBD6uhuyjdvv0ZwwLYA/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3371 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
006036	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Transformation plant for converting chromium waste into chemical products for the leather industry / Jaime Cot in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CIII, N° 3 (03/2008)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CIII, N° 3 (03/2008) . - p. 103 - 113 Titre : Transformation plant for converting chromium waste into chemical products for the leather industry Type de document : texte imprimé Auteurs : Jaime Cot, Auteur ; J. Cot-Gores, Auteur ; F. Fernandez-Hervas, Auteur ; Pedro J. Celma, Auteur ; Albert M. Manich, Auteur ; Agusti Marsal, Auteur Année de publication : 2008 Article en page(s) : p. 103 - 113 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The experience gained by our research team in recent years has led to the optimization of a quick and effective procedure for the complete dechromation of chromium waste. This procedure is based on the oxidation of chromium (III) to chromium (VI) through the action of hydrogen peroxide in an alkaline medium. The highly toxic chromium (VI) is stored in a stainless steel tank before being subsequently reduced to chromium (III), which can be reused in the tanning process. The oxidation reaction, at room temperature, leads to the formation of peroxochromates that have great oxidizing power and which significantly accelerate the pre-hydrolysis; corresponding to the maceration stage in the gelatine production process. In this way, gelatine or any other type of collagen biopolymer can be obtained in a single stage and with an excellent yield. We have designed an industrial transformation plant for chromium waste in chemical products used by the tanning industry. This plant consists of the following equipment: defibering machine, hydroextractive centrifuge, two reactors (dechromation and for obtaining biopolymers), tank for storage and reduction of chromium (VI), atomizer (optional), simple equipment for heating concentrated biopolymer solutions, transportation truck. Given that the overall investment has a payback back in five years, the cost of the plant can easily be borne by the tanner. This project has two objectives: firstly, to help solving an important environmental problem faced by the leather industry, which incurs significant costs in managing this type of waste; and secondly, to enable acceptable financial gains in terms of obtaining chemical products designed for the tanning industry. These products are: basic chromium (III) salts from the chromium waste, collagen biopolymers suitable for retanning, filling, basifying, deliming and glazing finishes that can partially and/or totally replace casein. Our proposed transformation plant for chromium waste was designed in such a way as to be adaptable to the individual circumstances of all interested leather industries, thus avoiding the need to build a communal plant, where the costs of transporting waste would have a negative effect on final savings. The plant is designed to process all types of chromium waste produced during the tanning process and in the subsequent stages of manufacture (fatliquoring, retanning, dyeing and finishing), and includes chromium waste with wool/hair (double-face). A financial study of the overall installation and the corresponding cost in obtaining the new chemical products was also been carried out and reveals significant savings for the tanner. En ligne : https://drive.google.com/file/d/1YMEn_JJMYoQ1bS88gsP7UcK8UX5vP8rl/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2578 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
009925	-	Périodique	Bibliothèque principale	Documentaires	Disponible

---

1 (1 - 2 / 2)