Some thermodynamic properties of NHk fixation by loess soil in plowing and clay layers are discussed.The. results indicate that the four ion adsorption equations commonly used can describe the properties of NHk fixati...Some thermodynamic properties of NHk fixation by loess soil in plowing and clay layers are discussed.The. results indicate that the four ion adsorption equations commonly used can describe the properties of NHk fixation in these soils under constant temperature. Among the four adsorption equations, the singlesurface Langmuir equation is the best. When the concentration of NH4Cl solution is 10-1 mol below, the Freundlich equation can be used.The changes of apparent standard free energy (△Go), enthalpy (△Ho) and entropy (△So) illustrate that NHk fixation in soil is an endothermic adsorption and spontaneous reaction, and the process can be enhanced by a higher temperature and clay content in soil.The "proper value of NHk fixation by soil (K1×qm) increased with increasing clay content and temperature. The heat of NHk fixation in soil (Qm) confirms the conclusions made in this paper.展开更多
文摘Some thermodynamic properties of NHk fixation by loess soil in plowing and clay layers are discussed.The. results indicate that the four ion adsorption equations commonly used can describe the properties of NHk fixation in these soils under constant temperature. Among the four adsorption equations, the singlesurface Langmuir equation is the best. When the concentration of NH4Cl solution is 10-1 mol below, the Freundlich equation can be used.The changes of apparent standard free energy (△Go), enthalpy (△Ho) and entropy (△So) illustrate that NHk fixation in soil is an endothermic adsorption and spontaneous reaction, and the process can be enhanced by a higher temperature and clay content in soil.The "proper value of NHk fixation by soil (K1×qm) increased with increasing clay content and temperature. The heat of NHk fixation in soil (Qm) confirms the conclusions made in this paper.
文摘研究了斑铜矿的浮选行为,并通过吸附量测试、红外光谱、吸附动力学及热力学计算研究丁基钠黄药(简称Na BX)在斑铜矿表面的吸附机理.斑铜矿在pH为5～9时可浮性较好,药剂在矿物表面的吸附属Freundlich模型的多分子层吸附;当pH为12时可浮性差,属于Lamgmuir模型的单分层吸附. Na BX在矿物表面吸附符合二阶动力学方程,是自发进行的化学吸附过程,通过热力学计算得出pH为9时的吸附反应比pH为12时更容易发生.红外光谱测试表明,当pH为5～9时Na BX在斑铜矿表面的吸附产物为Cu(BX)_2,Fe(BX)_3和(BX)_2,而当pH为12时的吸附产物为Cu(BX)_2.
