Department of Chemical & Petroleum Engineering, Alberta Ingenuity Centre for In-Situ Energy, University of Calgary, Calgary, Alberta, Canada.
J Colloid Interface Sci. 2011 Aug 1;360(1):233-8. doi: 10.1016/j.jcis.2011.04.056. Epub 2011 Apr 27.
This study investigates the effect of surface acidity and basicity of aluminas on asphaltene adsorption followed by air oxidation. Equilibrium batch adsorption experiments were conducted at 25°C with solutions of asphaltenes in toluene at concentrations ranging from 100 to 3000 g/L using three conventional alumina adsorbents with different surface acidity. Data were found to better fit to the Freundlich isotherm model showing a multilayer adsorption. Results showed that asphaltene adsorption is strongly affected by the surface acidity, and the adsorption capacities of asphaltenes onto the three aluminas followed the order acidic>basic and neutral. Asphaltenes adsorbed over aluminas were subjected to oxidation in air up to 600°C in a thermogravimetric analyzer to study the catalytic effect of aluminas with different surface acidity. A correlation was found between Freundlich affinity constant (1/n) and the catalytic activity. Basic alumina that has the lowest 1/n value, depicting strongest interactions, has the highest catalytic activity, followed by neutral and acidic aluminas, respectively.
本研究考察了氧化铝表面酸碱性对沥青质吸附及随后空气氧化的影响。在 25°C 下，使用三种具有不同表面酸性的常规氧化铝吸附剂，在浓度范围为 100 至 3000 g/L 的甲苯中进行了沥青质的平衡批量吸附实验。数据更符合 Freundlich 等温线模型，表明多层吸附。结果表明，沥青质的吸附强烈受表面酸性影响，而沥青质在三种氧化铝上的吸附容量顺序为酸性>碱性和中性。将吸附在氧化铝上的沥青质在热重分析仪中用空气氧化至 600°C，以研究具有不同表面酸性的氧化铝的催化作用。发现 Freundlich 亲和常数（1/n）与催化活性之间存在相关性。碱性氧化铝的 1/n 值最低，表明相互作用最强，具有最高的催化活性，其次是中性和酸性氧化铝。
