title: Sonocatalytic and sonophotocatalytic degradation of Rhodamine 6G containing wastewaters.
abstract: The present work deals with degradation of aqueous solution of Rhodamine 6G (Rh 6G) using sonocatalytic and sonophotocatalytic treatment schemes based on the use of cupric oxide (CuO) and titanium dioxide (TiO2) as the solid catalysts. Experiments have been carried out at the operating capacity of 2 L and constant initial pH of 12.5. The effect of catalyst loading on the sonochemical degradation has been investigated by varying the loading over the range of 1.5-4.5 g/L. It has been observed that the maximum degradation of 52.2% was obtained at an optimum concentration of CuO as 1.5 g/L whereas for TiO2 maximum degradation was observed as 51.2% at a loading of 4 g/L over similar treatment period. Studies with presence of radical scavengers such as methanol (CH3OH) and n-butanol (C4H9OH) indicated lower extents of degradation confirming the dominance of radical mechanism. The combined approach of ultrasound, solid catalyst and scavengers has also been investigated at optimum loadings to simulate real conditions. The optimal solid loading was used for studies involving oxidation using UV irradiations where 26.4% and 28.9% of degradation was achieved at optimal loading of CuO and TiO2, respectively. Studies using combination of UV and US irradiations have also been carried out using the optimal concentration of the catalysts. It has been observed that maximum degradation of 63.3% is achieved using combined US and UV with TiO2 (4 g/L) as the photocatalyst. Overall it can be said that the combined processes give higher extent of degradation as compared to the individual processes based on US or UV irradiations.
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Nileema B
authors.initials: NB
authors.lastname: Bokhale
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Snehal D
authors.initials: SD
authors.lastname: Bomble
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Rachana R
authors.initials: RR
authors.lastname: Dalbhanjan
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Deepika D
authors.initials: DD
authors.lastname: Mahale
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Shruti P
authors.initials: SP
authors.lastname: Hinge
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India.
authors.forename: Barnali S
authors.initials: BS
authors.lastname: Banerjee
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Near RTO, Pune 411001, India. Electronic address: ashishmohod2004@gmail.com.
authors.forename: Ashish V
authors.initials: AV
authors.lastname: Mohod
authors.affiliation: Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400019, India. Electronic address: pr.gogate@ictmumbai.edu.in.
authors.forename: Parag R
authors.initials: PR
authors.lastname: Gogate
mesh_terms: D020001:1-Butanol / Q000737:chemistry / Q000528:radiation effects; D057919:Biological Oxygen Demand Analysis; D002384:Catalysis / Q000528:radiation effects*; D003300:Copper / Q000737:chemistry; D016166:Free Radical Scavengers / Q000737:chemistry; D000432:Methanol / Q000737:chemistry / Q000528:radiation effects; D012235:Rhodamines / Q000032:analysis / Q000528:radiation effects*; D014025:Titanium / Q000737:chemistry; D014465:Ultrasonics / Q000379:methods*; D014466:Ultraviolet Rays; D062065:Wastewater / Q000032:analysis*
chemical_list: D020001:1-Butanol; D003300:Copper; D016166:Free Radical Scavengers; D000432:Methanol; D012235:Rhodamines; D014025:Titanium; D062065:Wastewater; C026188:rhodamine 6G; C009495:titanium dioxide; C030973:cupric oxide
keywords: COD removal; Intensification; Photocatalysis; Radical scavengers; Rhodamine 6G degradation; Sonolysis