Desulfurisation and ash reduction of pyrolysis carbon black from waste tires by combined Fe3+ oxidation-flotation. (15th January 2023)

• Record Type: Journal Article
• Authors: Li, Tao; Wang, Shuai; Chen, Wangyang; Niu, Jiahui; Li, Jinlong; Zhang, Fengbin; Feng, Yi; He, Yaqun; Zhang, Tao
• Is Part Of: Journal of cleaner production. Volume 384(2023)
• Publication Date: 2023-01-15
• Subjects: Waste tires -- Pyrolysis carbon black -- Oxidation leaching -- Flotation -- Desulfurisation and ash reduction; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.135489
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: The recycling of valuable carbon black (CB) of pyrolysis carbon black (CBp) from waste tires is important considering the conservation of secondary resources and the alleviation of potential hazardous effects on environment, but the high ash content hinders the high-value utilisation of CBp. In this work, the ash reduction and desulfurisation of CBp were studied using Fe 3+ in acid medium and flotation. The effects of different operating factors on the quality improvement of carbon black were investigated, and the properties of the products were analysed with morphology and phase characterisation technology. The Fe 3+ leaching results show that 90.27% yield and 11.53% ash content of clean CB were obtained when the leaching temperature of 25 °C, leaching time of 150 min, pulp density of 250 g/L, and Fe 3+ concentration of 99 kg/t. Then, flotation results show that 79.96% yield of clean carbon black and 9.14% ash content for flotation concentrate under the optimum flotation conditions: 25 g/L pulp density, 2, 500 g/t collector, 1, 000 g/L frother, and 0.25 m 3 /h aeration rate. In this study, minerals such as ZnS, SiO2 and CaCO3 were effectively removed. The results show that desulfurisation and ash reduction of CBp were achieved with Fe 3+ leaching and floatation. Graphical abstract: Image 1 Highlights: The beneficiation-metallurgy combined process is studied to purify CBp. Sulphur is produced when Fe 3+ oxidation leaching, and it can be recovered. The evaluation indexes and mechanism of ash reduction for Fe 3+ leaching are analysed. It has been proved that flotation can effectively remove SiO2 in CBp.