1. 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 0.02.04.06.08.010.012.0 C e / 10 -7 mol/L q e / 10 -7 mol/g This Journal is © The Royal Society of Chemistry 2002 Figure S1. Adsorption isotherm of 2-chlorophenol on RHA at room temperature of 23 0 C

2. y = 0.1729x + 6557.3 y = 0.3589x + 12390 0 50000 100000 150000 200000 250000 300000 0200000400000600000800000 1/C e (L mol -1 ) 1/q e (g mol -1 ) Phenol Resorcinol Figure S2a. The graphical representation of Langmuir isotherm for phenol and resorcinol obtained at 23 0 C.

3. y = 0.1102x + 613062 0 500000 1000000 1500000 2000000 2500000 3000000 3500000 4000000 0.E+005.E+061.E+072.E+07 3.E+07 1/C e (L mol -1 ) 1/q e (g mol -1 ) Figure S2b. The graphical representation of Langmuir isotherm for 2- chlorophenol obtained at 23 0 C.

4. y = 0.4519x - 3.1125 y = 0.6939x - 0.9752 y = 0.6965x - 1.2882 -7.0 -6.5 -6.0 -5.5 -5.0 -4.5 -4.0 -8.0-7.0-6.0-5.0-4.0 log C e log (q e ) 2-Chlorophenol Phenol Resorcinol Figure S3. The graphical representation of Freundlich isotherm for phenol, resorcinol and 2-chlorophenol obtained at 23 0 C.

5. 50 o C Figure S4. Effect of temperature on reaction between 1.0g of RHA and 5.0 x 10 -4 M pyrogallol (filled symbols) and 5.0 x 10 -4 M pyrocatechol (open symbols).