【摘要】：選擇苯甲腈為目標(biāo)污染物,研究添加不同熱解溫度制備小麥秸稈生物碳對黃土吸附苯甲腈的影響.研究表明:不加生物炭黃土對苯甲腈的吸附約8h達(dá)到平衡,而加入生物炭后,黃土對苯甲腈的吸附時(shí)間縮短,并隨著加入生物炭熱解溫度的升高,吸附平衡時(shí)間縮短越明顯,同時(shí),黃土對苯甲腈的飽和吸附量也顯著增加;添加生物炭黃土對苯甲腈的動力學(xué)吸附數(shù)據(jù)顯示較好的符合了準(zhǔn)二級動力學(xué)方程;無論是否添加生物炭,苯甲腈在黃土上的吸附都符合Freundlich吸附的等溫模型,隨系統(tǒng)溫度升高,添加生物炭黃土對苯甲腈的飽和吸附量也顯著增加,表明該吸附過程為吸熱反應(yīng);苯甲腈在黃土上的吸附等溫線符合C-型吸附等溫模式.計(jì)算結(jié)果顯示,平均吸附自由能E介于1.865~3.171k J/mol,表明苯甲腈在黃土上的吸附,無論是否添加生物炭,都以物理吸附為主;熱力學(xué)參數(shù)計(jì)算結(jié)果顯示,無論是否添加生物炭,黃土對苯甲腈的吸附過程中吉布斯自由能ΔGθ均小于0、熵變ΔS~θ和焓變ΔH~θ均大于0,表明土壤對苯甲腈的吸附為自發(fā)進(jìn)行的吸熱過程.研究結(jié)果說明,添加生物炭黃土對苯甲腈的吸附過程包含表面吸附和顆粒內(nèi)部擴(kuò)散、外部液膜擴(kuò)散等機(jī)制.
[Abstract]:The effect of wheat straw biocarbon prepared by adding different pyrolysis temperature on the adsorption of benzonitrile by loess was studied by using benzonitrile as the target pollutant. The results show that the adsorption time of benzonitrile is shortened after adding biochar, and the adsorption equilibrium time is shortened with the increase of pyrolysis temperature. At the same time, the saturated adsorption capacity of benzonitrile in loess also increased significantly. The kinetic adsorption data of benzonitrile by adding biocarbon loess showed that it was in good agreement with the quasi-second-order kinetic equation. No matter whether biological carbon is added or not, the adsorption of benzonitrile on loess accords with the isotherm model of Freundlich adsorption. With the increase of system temperature, the saturated adsorption capacity of benzonitrile on loess added with biochar also increases significantly, indicating that the adsorption process is endothermic. The adsorption isotherms of benzonitrile on loess are in accordance with the C-type adsorption isotherm model. The results show that the average adsorption free energy E is 1.865 鈮，

本文編號：2483254