Highly crystalline faujasitic zeolites from flyash

• Published in: Journal of hazardous materials Vol. 77; no. 1; pp. 123 - 131
• Main Authors: Rayalu, S, Meshram, S.U, Hasan, M.Z
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.10.2000; Elsevier
• Subjects: Applied sciences; Chemistry; Crystallization; Exact sciences and technology; Flyash-based zeolite; General and physical chemistry; Incineration; Ion-exchange; Microscopy, Electron, Scanning; Other industrial wastes. Sewage sludge; Pollution; Process standardisation; Refuse Disposal; Surface physical chemistry; Synthesis; Waste utilization; Wastes; Zeolites - analysis; Zeolites: preparations and properties; Process standardisation; Waste utilization; Flyash-based zeolite; Synthesis; Scanning electron microscopy; Chemical analysis; Waste treatment; Raw materials; Zeolite; Phase analysis; Experimental study; Inductive coupling plasma spectrometry; X ray diffraction; Optimization; Molecular sieve; Characterization; Fly ash; Industrial waste; Cation exchange capacity; Upgrading; Morphology; Preparation; Faujasite; Waste reuse; Coal power plant; Solid waste; Chemical composition; Atomic emission spectroscopy
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/S0304-3894(00)00212-0

The process for the synthesis of flyash-based zeolites (FAZs) are presented, which basically includes alkaline treatment of flyash by a fusion method, followed by hydrothermal crystallization. Zeolite-Y has been identified, and conditions have been optimized for their synthesis by the fusion method. Optimal conditions for synthesis of Zeolite-Y are a NaOH/flyash ratio of 1.2:1, fusion temperature between 500°C and 600°C, crystallization time of 8–10 h and crystallization temperature between 100°C and 110°C. The cation exchange capacity (CEC) of FAZ-Y ranges between 400 and 450 meq/100 g. The surface area of FAZs (500–600 m 2/g) compare well with the commercial zeolites procured from Mobil Oil. Morphological characterization of FAZ using scanning electron microscopy (SEM) reveals cubic structure, and XRD data reveal unit cells to be cubic system.