Characterization of spent bentonite recovered from winery waste to assess its recycling potential

ABSTRACT: The Canadian wine industry is associated with the production of a significant amount of spent bentonite (clay added to the wine for clarification) as a solid waste byproduct. To improve the sustainability of wine production, we must understand the physiochemical and toxicological characteristics of these wastes and facilitate its reuse and recycling for more environmentally friendly applications. In this study, we evaluated the properties of a spent bentonite sample obtained from local winery in the Okanagan region of British Columbia, Canada. We initially collected the liquid red wine waste and filtered bentonite by removing the organic matter. Bentonite filtrate was dried, powdered and characterized for physiochemical and toxicological properties. The surface area, pH, and organic matter (OM) were determined. Fourier transform infrared spectroscopy (FTIRS) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) analysis were used to examine the chemical and morphological properties. The toxicity characteristic leachate test (TCLP) was conducted to measure the total heavy metal concentration. The results showed the spent bentonite has low pH (3.5 to 4), high OM (17 to 20 %), high K (373 to 557 mg/kg) and Mg (50 mg/kg), and lower Brunauer- Emmett-Teller (BET) surface area compared to the virgin. The TCLP results showed the concentration of heavy metals including Ba, Cu, As, Ti, Ni and Fe were relatively higher in the spent bentonite. Occurrence of new peaks/bands on the FTIR spectra of spent bentonite confirmed the existence of organic functional groups resulting from the organic components in the waste. According to SEM-EDS, the microstructure of the spent bentonite exhibited a flocculated arrangement and the ratio Al/Si decreased in the spent bentonite. Overall, the tests indicated that significant changes occurred in the physiochemical and toxicological characteristics of bentonite during the wining process. Identifying and quantifying these major property variations opens the ways to recycle this solid waste for more environmentally friendly purposes and creates a new platform for sustainable consumption and waste management in the future.

RÉSUMÉ: La propriété caracterisation de filtrer la bentonite d’ vin industriellle de fixer son recyclage potentiel le total perdre significatif de la bentonite est produit annuellement en residu d’ vin fabrication en Canadien industrielle. Comprendr caracteristique physico-chimique et toxicologique de ces pertes, facilite de reutiliser et recyclage pour environment amical application dans cette etude nous evaluer la proprieté de different perdre des echantillons bentonite obtenir de quelques facteurs d’extrait regional en Okanagan region de British Columbia, Canadien. Au depart nous rassemblé des perdres et filtres la bentonite. De la bentonite filtrat ensuit elle ait secheé poudré pour caracterisasion de physico-chimique et toxicologique proprieté. La etendue surface, pH, matiére organique (MO), ait determiné. Fourier transform infra-rouge spectroscopy (FTIRS), scanning electron microscopy coupler avec energie dispersive spectroscopy (SEM-EDS) usage pour comprendre changement de chimique et morphologique l’ epreuve caracteristique filterer toxicité (ECFT), nous été conduire de mesurer la concentration de lourd metal element. Ces resultats montre que la perte de la bentonite avais bas pH (3.5 a 4), haut MO (17 a 20 %), haut K plus (373 a 557 mg/Kg), et Mg (50 mg/Kg) et plus bas Brunauer- Emmett-Teller (BET) la surface etendue comparer avec a virgin. De resultat de ECFT montre la concentration de lourd metal compris Ba, Cu, As, Ti, Ni et Fe relativement ait été plus elevé dans la bentonite, evenement de nouveau pic/bonde dans FTIR de perdre de spectre de la bentonite. Confirmer en existence d’organique avec groups fonctionnels resultat dans organique composant dans la perte conforme a (SEM-EDS) en microstructure de perte bentonite un floculer arrangement et de la proportion Al/Si diminuer en perdre bentonite. Combinaison, des essais indiques ces significatif changement se produire en physico-chimique et toxicologique caracteristique de la bentonite en dureé de procedé identité et qualitative ce majeur difference proprieté ouvrir le chemin a recycler ce solid prdre pour plus environment amical conseiller et cree’s nouveau platform pour sustenable consummation et perdre administration a’ l’avonir.