Table 3.

Decolorization of dyes using Cu(II), Ni(II), and Co(II) complexes.

Dye/metal complex (5 mg)	% of removal at pH's without UV			% of removal at pH's with UV
	3.0	8.2	12.0	3.0	8.2	12.0
Methylene blue	No change	13.82	24.0	5.69	29.93	47.73
Co(L)2Cl2	14.78	14.78	44.66	9.24	9.24	83.07
Ni(L)2	7.9	29.93	35.72	38.8	22.18	80.44
Cu(L)2Cl2·2H2O	33.92	8.83	33.44	43.33	3.3	88.80