Catalytic pyrolysis of spent bleaching clay for its regeneration and simultaneously producing aromatic hydrocarbons. (10th January 2023)

• Record Type: Journal Article
• Authors: Li, Kai; Li, Zhu-yu; Zhang, Cheng-Bo; Zhao, Jia-qi; Zhao, Li; Liu, Ji; Ma, Shan-wei; Lu, Qiang
• Is Part Of: Journal of cleaner production. Volume 383(2023)
• Publication Date: 2023-01-10
• Subjects: Catalytic pyrolysis -- Spent bleaching clay -- Aromatic hydrocarbon -- Regeneration; 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.2022.135567
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: This study was focused on the value-increment of spent bleaching clay (SBC) to produce aromatic hydrocarbons and regenerated bleaching clay (RBC) via ex-situ catalytic pyrolysis with HZSM-5. The catalytic pyrolysis experiments were conducted to clarify the regulatory functions of pyrolytic temperature and SBC-to-HZSM-5 ratio (S/H) on the product distribution and aromatics generation. The adsorbed oil in SBC could be decomposed almost completely at 450 °C. The optimum aromatics yield of 3.49 wt% was achieved at catalytic temperature of 600 °C and S/H of 15. The solid product obtained under this condition underwent calcination at 500 °C and acid treatment successively to prepare RBC. The treatment did not affect the montmorillonite structure of clay. The RBC possessed good porous structures with newly generated micropores. The specific surface area and pore volume of RBC reached 163.32 m 2 /g and 0.29 cm 3 /g, higher than those of 146.17 m 2 /g and 0.25 cm 3 /g of fresh activated bleaching clay (ABC), indicating the better adsorption performance of RBC. Graphical abstract: Image 1 Highlights: Catalytic pyrolysis was employed for the recycling of spent bleaching clay. The highest yield of aromatic hydrocarbons could reach 3.49 wt%. Calcination and H2 SO4 activation allowed the regeneration of bleaching clay. The regenerated bleaching clay possessed good porous structures.