软模板法石墨烯气凝胶的可控制备及其吸油性能

以环己烷为油相，氧化石墨烯（GO）为稳定剂，采用Pickering乳液法制备石墨烯气凝胶，利用电子显微镜对Pickering乳液进行表征，利用扫描电镜（SEM）、傅里叶红外光谱（FTIR）、拉曼光谱（Raman）、X射线衍射（XRD）对制得的石墨烯气凝胶进行表征。对比Pickering乳液的液滴大小与气凝胶的孔径大小可知，通过软模板法实现了对气凝胶的孔径控制，通过控制均质机的转速来调控气凝胶的孔径大小，当均质机转速分别为10000r/min、12000r/min和15000r/min时，所得石墨烯气凝胶的孔径分别为45μm、35μm和30μm左右，通过调节油水比实现了气凝胶的密度与孔隙率的控制，油水比越大，所得气凝胶的密度越小，孔隙率越大，通过延长还原时间可增强石墨烯气凝胶的机械性能。将所得气凝胶用于油品的吸附，可快速吸附水上浮油及水底重油，而且几乎不吸附水；对同一油品而言，气凝胶的吸附能力与其制备时的油水比呈正相关，采用挤压的方式实现石墨烯气凝胶的循环利用，经过10次循环再生后气凝胶的吸附能力仅有15%的损失。

Controllable preparation of graphene aerogels with soft templates and its adsorption on oils

Graphene aerogels were prepared by Pickering emulsion using cyclohexane as oil phase and graphene oxide (GO) as stabilizer. The Pickering emulsion was characterized by the electron microscope. The graphene aerogels was characterized by SEM, FTIR, Raman and XRD. By comparing the droplet size of Pickering emulsion and the pore size of aerogels, the pore size control of aerogels can be achieved by soft template method. By adjusting the agitation speed of the high-speed homogenizer, the pore size of the aerogel was adjusted. When the agitation speed of the high-speed homogenizer was 10000r/min, 12000r/min and 15000r/min, the pore size of the obtained graphene aerogels was 45μm, 35μm and 30μm, respectively. The density and porosity of aerogels were controlled by adjusting the oil/ water ratio during its preparation. It was observed that with the increase of oil/water ratio, the aerogel density reduced, while the porosity increased. The mechanical performance of graphene aerogels can be enhanced by extending the time of reduction. The obtained aerogels were used for the adsorption of oils. Graphene aerogels can adsorb floating oil and bottom heavy oil rapidly, and hardly adsorb water. For the same oil, the adsorption capacity of aerogels was positively correlated with the oil/water ratio. The recycling of graphene aerogels was achieved through extrusion method. After 10 cycles of regeneration, the adsorption capacity of aerogels decreased only by 15%.