Titre : |
Remediation of spent vegetable tannins from waste tanning liquor through coagulation and ultrasound pre-treatment : a sustainable approach |
Type de document : |
texte imprimé |
Auteurs : |
Resmi Mohan, Auteur ; R. Muthukumar, Auteur ; R. Shivaji Ganesan, Auteur ; S. Shrividhya, Auteur ; Venkatasubramanian Sivakumar, Auteur |
Année de publication : |
2022 |
Article en page(s) : |
p. 367-378 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Acacia et constituants Alun Argile Chaux Chlorure de baryum Chlorure de zinc Coagulation Décantation Eaux usées -- Epuration Polyélectrolytes Précipitation (chimie) Tanins végétaux Tannage -- Déchets Ultrasons
|
Index. décimale : |
675.2 Préparation du cuir naturel. Tannage |
Résumé : |
Vegetable tanning is one of the oldest methods of tanning. Vegetable tannins present in spent tanning liquor necessitates suitable remediation measures for sustainable solution. Vegetable tanning agent, wattle extract powder and vegetable tanning process spent liquor collected from a commercial tannery were used for the experiments. In the present approach, natural clay has been employed for the coagulation of spent vegetable tannins. Various other suitable precipitating agents such as zinc chloride (ZnCl2), barium chloride (BaCl2), ferric alum, lime and poly-electrolyte have also been studied for their efficacy in the treatment process and their requirement optimized. The efficacy of coagulation was monitored through settling characteristics of precipitation process and % settled volume for a given time. In the case of wattle powder, better settling of tannins was obtained due to combined use of optimized amount of clay and ZnCl2. Whereas, ultrasound pre-treatment provided further enhancement. In the case of spent tannery vegetable tanning liquor, ultrasound pre-treatment of polyelectrolyte along with optimized amount of normal lime, clay and ferric alum provided rapid settling behavior, with steady state achieved in 20 minutes with settled volume of ~10 ml. Similar trend was also achieved (10 ml, 8 min). for ultrasound pre-treated optimized clay with the use of other agents as normal. There was a significant reduction in particle size of clay (from 539 nm to 298 nm) through ultrasound pre-treatment (20 min.), leading to more surface area facilitating the coagulation process. This method could be useful for remediation of vegetable tannins present in spent vegetable tanning liquors using available natural material clay and shall also be extended to other streams. The present study has explored the ultrasound assisted coagulation science and technology for remediation of wastewater in general, whereas, spent vegetable tanning liquor in specific. |
Note de contenu : |
- INTRODUCTION : Chemistry of vegetable tannins - Coagulation treatment for vegetable tannins use of soil clay in coagulation process : originality of the present work - Use of ultrasound in coagulation process - Effect of other coagulating agents
- MATERIALS AND METHODS : Materials used - Ultrasound equipment
- METHODS : Preparation of synthetic vegetable tanning liquor (SVT) - Settling characteristics and % settle volume - Optimization of zinc chloride, barium chloride and clay - Effect of ultrasound pre-treatment on optimized zinc chloride - Effect of combination of zinc chloride and clay - Optimization of ferric alum and clay - Optimization of poly electrolyte - Effect of ultrasound pre-treatment on clay with optimized normal ferric alum and polyelectrolyte - Effect of ultrasound pre-treatment on polyelectrolyte with optimized normal clay ferric alum - Effect of lime on ultrasound pre-treated optimized polyelectrolytes in spent tannery vegetable tanning liquor - Effect of lime on ultrasound pre-treated optiimzed clay in spent tannery vegetable tanning liquor - Particle size analysis of clay samples
- RESULTS AND DISCUSSIONS : Optimization of barium chloride and zinc chloride - Optimization of clay with optimized zinc chloride - Effect of ultrasound pre-treatment on optimized zinc chloride - Effect of combined use of zinc chloride and clay - Optimization of ferric alum - Optimization of clay with optimized ferric alum - Optimization of poly electrolyte - Effect of ultrasound pre-treatment on optimized clay with normal optimized ferric alum and polyelectrolyte - Effect of ultrasound pre-treatment on optimized polyelectrolyte with optimized normal clay ferric alum - Effect of lime on ultrasound pre-treated polyelectrolytes in spent tannery vegetable tanning liquor - Effect of lime on ultrasound pre-treated clay in spent tannery vegetable tanning liquor - Particle size analysis of clay and effect of ultrasound treatment
- Table 1 : Optimization of lime in spent tannery vegetable tanning liquor and corresponding pH values
- table 2 : Optimization of different coagulants on SVT tannins or spent tannery vegetable tanning liquor coagulation for facilitating the settling process
- Table 3 : Effect of different optimized coagulants and influence of ultrasound pre-treatment on SVT tannins or spent tannery vegetable tanning liquor coagula(tion and settling rate characteristics during the settling process
- Table 4 : Effect of ultrasound (150 W at 20 kHz) on the particle size distribution of clay samples (1 g in 100 ml) |
DOI : |
https://doi.org/10.34314/jalca.v117i9.6167 |
En ligne : |
https://drive.google.com/file/d/11EepJ0UXlEqnC3EVIEXaqeR-iT3Jm2_r/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=38076 |
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CXVII, N° 9 (09/2022) . - p. 367-378