| Titre : |
Dechroming of chromium-containing leather waste with low hydrolysis degree of collagen |
| Type de document : |
texte imprimé |
| Auteurs : |
Wei Ding, Auteur ; Xuepin Liao, Auteur ; Wenhua Zhang, Auteur ; Bi Shi, Auteur |
| Année de publication : |
2015 |
| Article en page(s) : |
p. 129-133 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Catégories : |
Chaux
Collagène -- Détérioration
Cuirs et peaux -- Déchets -- Recyclage
Déchromage
Hydrolyse
Séparation (technologie)
Sulfurique, Acide
|
| Index. décimale : |
675.2 Préparation du cuir naturel. Tannage |
| Résumé : |
Dechroming is essential for utilization of chromium-containing leather wastes. Strong hydrolysis conditions favour breaking of the Cr and collagen linkage, but lead to a high degree of hydrolysis of the collagen se that the separation of chromium from the gelatinous hydrolysates becomes difficult. In this research, a mild acid-alkali alternate treatment of the waste with hydrolysis assistants was investigated, so as to develop a technology that has high dechroming level and low hydrolysis degree of collagen. A satisfactory dechroming method with four steps was finally obtained and the reaction conditions for each step were optimized as follows. Step 1 — waste in the solution with 2g1L NaOH and 40g/L urea {hydrolysis assistant) was stirred for 0.5 hours at 40°C. Step 2 — waste in 50g/L sulfuric acid solution was stirred for 1 heur at 40°C. Step 3 — waste in 40 g/L Cap% suspension was stirred for 2 hour at 30°C. Step 4 — waste in 50g/L suffuric acid solution was stirred for 1 hour at 30°C. With this method, total extent of the dechroming of the waste was higher Chan 97% while the hydrolysis degree of collagen was lower than 10%. |
| Note de contenu : |
- MATERIALS AND METHODS : Materials - Dechroming procedure of the leather waste - Estimation of the degree of hydrolysis of collagen
- RESULTS AND DISCUSSION : Effect of hydrolysis assistant on extent of dechroming - Effect of reaction temperature on dechroming extent - Effect of sulfuric acid concentration on dechroming extent - Effect of calcium hydroxide concentration on extent of dechroming - Hydrolysis degree of collagen |
| En ligne : |
https://drive.google.com/file/d/190QFQUqFJeTolMygTcMeLAUQr_rYV12n/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24257 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 99, N° 3 (05-06/2015) . - p. 129-133
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Dechroming of chromium-containing leather waste with low hydrolysis degree of collagen in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 99, N° 3 (05-06/2015)
