| Adsorption and desorption of Cu2+ by humic acids, peat, greenery waste, activated greenery waste and a calcareous Chao Soil were investigated with the batch method. The results showed that adsorptions of Cu2+ by these materials increased with the increase of Cu2+ concentration in the equilibrium solution at the same pH. Both Langmuir and Freundlich equations fitted the adsorption data well. When initial concentration of Cu2+ was relatively low, the adsorption capacity of Cu2+ by greenery waste, activated greenery waste and peat was not affected by the change of medium pH. However, when initial concentration of Cu2+ was relatively high, the adsorption was increased with the increasing pH value, but the desorption rate of pre-adsorbed Cu2+ changed with pH oppositely. The adsorption capacity of Cu2+ by humic acids and the calcareous Chao Soil increased with rising pH, while the desorption rate of pre-adsorbed Cu2+ increased with the increase in pH firstly and then decreased with the further increase in pH. The adsorption capacity of Cu2+ by these materials followed the order：greenery waste>activated greenery waste>peat>humic acids>calcareous Chao Soil, which suggested that greenery waste, activated greenery waste, and peat had strongest ability to fix Cu2+ among four organic materials and a soil. Greenery waste is a wonderful alternative of peat to remedy Cu contaminated urban soils. |
