Department of Chemical and Biomolecular Engineering, Rice University , Houston, Texas 77005, United States.
McKetta Department of Chemical Engineering, The University of Texas at Austin , Austin, Texas 78712, United States.
Langmuir. 2016 Oct 11;32(40):10244-10252. doi: 10.1021/acs.langmuir.6b01975. Epub 2016 Sep 27.
The static adsorption of CE, which is a highly ethoxylated nonionic surfactant, was studied on different minerals using high-performance liquid chromatography (HPLC) combined with an evaporative light scattering detector (ELSD). Of particular interest is the surfactant adsorption in the presence of CO because it can be used for foam flooding in enhanced oil recovery applications. The effects of the mineral type, impurities, salinity, and temperature were investigated. The adsorption of CE on pure calcite was as low as 0.01 mg/m but higher on dolomite depending on the silica and clay content in the mineral. The adsorption remained unchanged when the experiments were performed using a brine solution or 0.101 MPa (1 atm) CO, which indicates that electrostatic force is not the governing factor that drives the adsorption. The adsorption of CE on silica may be due to hydrogen bonding between the oxygen in the ethoxy groups of the surfactant and the hydroxyl groups on the mineral surface. Additionally, thermal decomposition of the surfactant was severe at 80 °C but can be inhibited by operating in a reducing environment. Under reducing conditions, adsorption of CE increased at higher temperatures.
使用高效液相色谱（HPLC）结合蒸发光散射检测器（ELSD）研究了不同矿物上 CE（高度乙氧基化的非离子表面活性剂）的静态吸附。特别感兴趣的是表面活性剂在 CO 存在下的吸附，因为它可用于提高采收率应用中的泡沫驱油。考察了矿物类型、杂质、盐度和温度的影响。CE 在纯方解石上的吸附低至 0.01mg/m，但在白云石上的吸附更高，具体取决于矿物中的二氧化硅和粘土含量。当使用盐水溶液或 0.101 MPa（1 atm）CO 进行实验时，吸附保持不变，这表明静电力不是驱动吸附的主要因素。CE 在二氧化硅上的吸附可能是由于表面活性剂乙氧基中的氧与矿物表面上的羟基之间形成氢键。此外，表面活性剂在 80°C 时严重热分解，但在还原环境下操作可以抑制。在还原条件下，CE 的吸附在较高温度下增加。
