Absorption Of Pb (?) And Cd (?) With Bamboo Charcoal And Modified Bamboo Charcoal

After the pretreatment, Bamboo Charcoal(BC) and Modified Bamboo Charcoal(EBC) were chemically modified with succinic acid. Then explore the adsorption of BC and EBC for Pb(?) and Cd(?).The static test talk about four element factor that include solution concentration, p H value, temperature and absorber dosage. Then fitting test result for different dynamical model such as pseudo-first order kinetic model, pseudo-second order kinetic model and internal diffusion model. Last, we explained the adsorbing capacity in different temperate and different solution concentration. Then fitting test result for thermodynamic model such as Freundlich model and Langmuir model. According to that, we talk about the thermodynamic model and adsorption mechanism.Bamboo Charcoal(BC) were chemically modified with succinic acid. Fourier Transform Infrared Spectroscopy(FTIR) and Scanning Electron Microscope(SEM) were applied to analyze the material microstructure and its chemical bond of the adsorbent. The result of SEM shows the structure of BC which processed at high temperaturemaintain the basic types of bamboo and EBC has high--dispersion. The result of SEM shows there are a large number of hydroxyl in both of them. With compare, it finds the carboxyl group(-COOH) were increase, and hydroxyl group(-OH) were decrease. When the temperature is 298 K and Ph is 5, 0.2g of BC and EBC were added respectively into 100 m L 50mg/L Pb(?), the adsorption capacity increase from 13.48 mg·g-1 to 17.94 mg·g-1. 0.6g of BC and EBC were added respectively into 100 m L 50mg/L Cd(?) solutions, the adsorption capacity increase from 3.73mg·g-1 to 4.94 mg·g-1?The result shows that with the increase of solution concentration, p H value and temperature and with the decrease of absorber dosage, the adsorption capacity increase. Solution concentration, p H value and absorber dosage has bigger effect on the adsorption capacity. But the change of temperature has less effect on the result. When p H is 2~3, the adsorption efficiency is very poor, When p H increase from 3 to 4, the adsorption capacity has improved significantly. When p H increase from 5 to 6, the adsorption capacity also has improved but the rate of rise is less than the previous stage. The higher the temperate is, the better the adsorption capacity is.The process for the adsorption of BC and EBC for Pb(?) and Cd(?) all fit for the pseudo-second order kinetic model. The coefficient of association were greater than 0.999. According to the research of thermodynamic model, it show that Langmuir model is more fit for the process the adsorption of Pb(?); Freundlich model is more fit for the process the adsorption of Cd(?). Because of ? H>0, the higher temperature can enhance the adsorption capacity. The reaction shows it a spontaneous reaction with ?G<0. The adsorption entropy increase as ?S>0.