| The Lignocellulose/montmorillonite Nanocomposite(LNC/MMT nanocomposite) and Xanthoceras sorbifolia Bunge husk activated carbon, were prepared with lignocellulose, montmorillonite and the husk of Xanthoceras sorbifolia Bunge. As the adsorption, they were used for the Hg(II), Ni(II) adsorption and desorption experiments: The experiments conditions,which includ different initial concentration of solution, adsorption time, adsorption temperature and p H, were investigated. According to the result of the experiments, the condition of the maximum adsorbing capacity was obtained. The adsorption kinetics model and the adsorption isotherm were studied at the same time, in order to make clear the adsorption mechanism of two kinds of adsorbent.The influences on the concentration of desorption solution in the maximum amount of desorption, desorption time and desorption temperature were explored via desorption experiment., The recycle was proved via through the cycle of adsorption and desorption experiments, SEM, EDX and FT-IR, were to characterisate the changes of the structure and surface property of the two kinds of adsorbent.The main results are as follows:1 Adsorption impact factor experiments show that the best impact factors: initial concentration of Hg(II) solution for the tendency is 0.8 mmol/L, adsorption time is 120 min, adsorption temperature is 50 ℃, the p H is 4, LNC/MMT nanocomposite for Hg(II) the maximum adsorption capacity is 79.32 mg/g; When Ni(II) solution to the initial concentration of is 0032 mol/L, adsorption temperature is 70 ℃, the p H value is 6.8, adsorption time is 40 min LNC/MMT nanocomposite is the measure of the saturated adsorption of Ni(II) is 94.86 mg/g; When the initial concentration of Hg(II) solution is 0.0024 mol/L, adsorption time is 60 min, adsorption temperature is 35 ℃, the p H value is 6 activated carbon for Hg(II) the maximum adsorption capacity is 235.10 mg/g; When Ni(II) solution to the initial concentration is 0.0056 mol/L, adsorption time is 90 min, adsorption temperature is 60 ℃, the p H value is 8 activated carbon for Ni(II) the maximum adsorption capacity is 110.33 mg/g. Through dynamic model and the adsorption isotherm studies have shown that four results conform to the pseudo secondary dynamics equation and the Langmuir adsorption isotherm equations.2 Desorption experiment results show that the optimal conditions of desorption effect: when the concentration of the HNO3 solution is 0.3 mol/L, reaction temperature is 30℃, time is 30 min, LNC/MMT nanocomposite for Hg(II) the biggest desorption quantity is 66 mg/g; When the concentration of the HNO3 solution is 0.2 mol/L, the time is 30 min, established when the reaction temperature is 60℃,LNC/MMT nanocomposite for Ni(II) the biggest desorption quantity is 80.79 mg/g; When the concentration of the HNO3 solution is 0.48 mol/L, time is 50 min, reaction temperature is 40℃ style activated carbon for Hg(II) the biggest desorption quantity up to 231 mg/g; When the concentration of the HNO3 solution is 0.2 mol/L, the time is 30 min, reaction temperature is 50℃ style activated carbon for Ni(II) the biggest desorption quantity up to 81.34 mg/g. Respectively through two kinds of adsorbent for adsorption and desorption cycle four times experiments show that both kinds of adsorbent is recycled.3 Established the structure characterization results show that the LNC/MMT nanocomposite and Xanthoceras sorbifolia Bunge husk activated carbon are scattered with pore structure, the microstructure of Hg(II) and Ni(II) adsorption, adsorption of Hg(II) and Ni(II), the adsorbent surface structure properties change significantly, recoverable structure before adsorption, desorption and established that LNC/MMT nanocomposite and Xanthoceras sorbifolia Bunge husk activated carbon has better circulation regeneration. |
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