Table 1.

Results on detoxification of methyl orange (MO) as under different conditions (MO concentration, pH, TiO₂ concentration and solar intensity). Reprinted from Ref. [254], Copyright (2002), with permission from Elsevier.

Rate Constant k of Degradation of TiO2 (h−1) in Different Time with Different Solar Intensities W h/m2			Effect of Concentration on the Degradation Rate (h−1) during April 2001
Month	1st Rate Constant	Solar Intensity	[MO] April 2001	k (465 nm)	R 2	pH before Reaction	pH after Reaction
July 1999	0.6195	4480	2 × 10−3 M	0.0412	0.94	6.4	6.1
November 1999	0.367	2535	4 × 10−4 M	0.1329	0.96	6.4	6.0
December 1999 (cloudy)	0.2455	2177	8 × 10−5 M	0.2010	0.98	6.5	6.1
January 2000	0.3314	3060	4 × 10−5 M	0.6393	0.92	6.5	6.4
February 2000	0.6489	3419	1 × 10−5 M	0.2912	0.90	5.9	6.2
March 2000	0.7953	4255
May 2000	0.5445	4814
June 2000	0.4645	3969
October 2000	0.3491	3970