The investigation of catalytic ozonation and integrated catalytic ozonation/biological processes for the removal of phenol from saline wastewaters

• Published in: Journal of hazardous materials 2009-11, Vol.171 (1), p.175-181
• Main Authors: Moussavi, Gholamreza, Khavanin, Ali, Alizadeh, Rahimeh
• Format: Article
• Language: English
• Subjects: Advanced oxidation process; Applied sciences; Biological; Biological and medical sciences; Biological treatment; Bioreactors; Biotechnology; Carbon - chemistry; Catalysis; Catalysts; Catalytic ozonation; Catalytic reactions; Chemical engineering; Chemistry; Crack opening displacement; Degradation; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; General purification processes; Hydrogen-Ion Concentration; Kinetics; Methods. Procedures. Technologies; Others; Oxygen - chemistry; Ozone - chemistry; Phenol; Phenol - analysis; Phenol - isolation & purification; Pollution; Reactors; Saline; Saline wastewater; Salts - chemistry; Sodium Chloride - chemistry; Temperature; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Time Factors; Various methods and equipments; Waste water; Wastewaters; Water Pollutants, Chemical - analysis; Water Purification - methods; Water treatment and pollution
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2009.05.113

The effectiveness of the catalytic ozonation process (COP) with a GAC catalyst was assessed based on the degradation and COD removal of phenol from the saline wastewater, as compared with the single ozonation process (SOP). The COP attained a much higher level of phenol degradation compared to the SOP. The influence of several variables was investigated, including pH of solution, NaCl concentration, and dosage of GAC, for their effects on COP phenol degradation in a synthetic saline wastewater. The maximum degradation of phenol was achieved at pH 8 and 20 g/L GAC. NaCl had no adverse effect on phenol removal at ranges between 0.5 and 50 g/L. The activated carbon acted mostly as a catalyst for ozone decomposition, and the subsequent generation of hydroxyl radicals. Furthermore, the GAC preserved its catalytic properties after 5 times reuse. The capability of a biological process to treat COP effluent was also investigated. Results showed that a 10 min reaction time in COP under optimum conditions reduces the concentrations of phenol and COD to an acceptable level for efficient post-treating in a suspended growth bioreactor at a short aeration time of 4 h. Thus, the integration of COP with a biological process is proven to be a technically and economically effective method for treating saline wastewaters containing recalcitrant compounds.