Adsorption of o-dihydroxybenzene on soil and modified soil(ammonium -CTMAB modified with 16 alkyl three methyl bromide) was studied.Adsorption thermoisopleth and adsorption dynamics,and influence of pH value and ion intensity to adsorption were investigated.The results showed that the modified soils have higher ability for o-dihydroxy benzene than unmodified one.Thermoisopleth of adsorption of o-dihydroxy benzene accords with Langmuir isotherm.The adsorption speed of o-dihydroxy benzene accords with the fir...