State Key Laboratory of Petroleum Pollution Control, Xi'an Shiyou University, Xi'an 710065, China.
Shaanxi Province Key Laboratory of Environmental Pollution Control and Reservoir Protection Technology of Oilfields, Xi'an Shiyou University, Xi'an 710065, China.
Molecules. 2022 Nov 2;27(21):7459. doi: 10.3390/molecules27217459.
The treatment of oilfield wastewater with high crude oil content and complex composition is a problem requiring considerable attention. In order to effectively remove crude oil contained in wastewater, in this work, rice straw, as an oil-absorbing material, was modified and used as a sorbent for crude oil. Rice straw was modified with alkali and cetyltrimethylammonium chloride (CTAC) by simple substitution reaction. The adsorption capacity of modified rice straw for oil was evaluated. The results illustrate that the adsorption rate of rice straw for crude oil was increased from 0.83 to 8.49 g/g, with the optimal conditions of 18% NaOH reacted for 90 min at 50 °C and 2% CTAC reacted for 60 min at 20 °C. The proposed modification method could be used for different materials to enhance the adsorption rate. The results of the contact angle test show that the modified straw changed from hydrophilic to hydrophobic, which may be the main reason for the improvement in the oil absorption rate. Finally, the surface structure of rice straw was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and N adsorption-desorption isotherms, which further confirmed the hydrophobicity of the modified rice straw.
处理高含原油且成分复杂的油田废水是一个需要高度关注的问题。为了有效去除废水中所含的原油，在这项工作中，我们选用稻草作为吸油材料，通过简单的取代反应对其进行改性，将其用作原油的吸附剂。我们用碱和十六烷基三甲基氯化铵（CTAC）对稻草进行改性，评估了改性稻草对油的吸附能力。结果表明，稻草对原油的吸附速率从 0.83 g/g 提高到了 8.49 g/g，最佳条件为 50°C 下用 18%的 NaOH 反应 90 分钟，20°C 下用 2%的 CTAC 反应 60 分钟。所提出的改性方法可用于不同材料，以提高吸附速率。接触角测试结果表明，改性后的稻草由亲水变为疏水，这可能是吸附速率提高的主要原因。最后，通过 X 射线衍射（XRD）、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和 N2 吸附-脱附等温线对稻草的表面结构进行了表征，进一步证实了改性稻草的疏水性。
