(1. 后勤工程學(xué)院 油品應(yīng)用工程系, 重慶 400016;
2. 湘潭大學(xué) 機(jī)械工程學(xué)院, 湘潭 411105)
摘 要: 對(duì)月桂酸在不同溫度下自十二烷溶液中在鐵表面的等溫吸附進(jìn)行了實(shí)驗(yàn)研究。結(jié)果表明: 在298~323 K的溫度范圍內(nèi), 恒溫?cái)嚢? h就基本達(dá)到了吸附平衡。 在298 K和323 K兩種溫度下的吸附等溫線(xiàn)均屬S型曲線(xiàn), 說(shuō)明月桂酸在鐵表面形成了表面反膠團(tuán)或發(fā)生了合作吸附。用以?xún)呻A段吸附模型為基礎(chǔ)的吸附等溫線(xiàn)通用公式處理2種溫度下的吸附實(shí)驗(yàn)數(shù)據(jù), 結(jié)果表明實(shí)驗(yàn)值與擬合曲線(xiàn)有較好的一致性。熱力學(xué)計(jì)算表明: 月桂酸在鐵表面的締合過(guò)程不是熵驅(qū)動(dòng)的過(guò)程, 故形成的表面締合物是表面反膠團(tuán), 其聚集數(shù)約為3;極性基間的極性相互作用或氫鍵作用在表面反膠團(tuán)形成過(guò)程中起主要作用。
關(guān)鍵字: 月桂酸;鐵; 吸附等溫線(xiàn); 兩階段吸附模型; 表面反膠團(tuán)
(1. Department of Petroleum Applied Engineering,Logistic Engineering College, Chongqing 400016, P.R.China;
2. College of Mechanical Engineering, Xiangtan University, Xiangtan 411105, P.R.China)
Abstract:The isothermal adsorption of dodecanic acid from dodecane solution on iron has been measured under different temperature. The experiment results show that the adsorption equilibrium is obtained after 4 h isothermal stirringduring the temperature from 298 K to 323 K. The adsorption isotherms under 298 K and 323 K are S shape, these indicate that dodecanic acid forms surface inverse micelles on iron or leads to cooperative adsorption. The adsorption experiment data under two temperature are handled using the general formula of adsorption isotherm based on two stages adsorption model, the results show that the experiment data are in good accordance with the theoretical curve. Thermodynamical calculation results indicate that surface association process of dodecanic acid on iron isnot an entropy drive process, so the association material on iron is surface inverse micelle, the gathering amount is about 3. The polar mutual action betweenpolar groups and hydrogen bond action plays a chief role in forming the surface inverse micelle.
Key words: dodecanic acid; iron; adsorption isotherms;two stages adsorption model; surface inverse micelle


