Preparation and performance evaluation of graphene/hydroxypropyl methylcellulose composite aerogel for high viscosity oil adsorption. Issue 5 (October 2022) - Guo, Qilin
Abstract: With the society development, offshore oil leakage has become a global concern. The high viscosity and low fluidity of crude oil tend to prevent its diffusion to porous adsorbents, resulting in inefficient oil spill handling. To deal with the problem of intractable oil spills at sea, a two-step hydrothermal reduction method combined with ice templates was used to prepare graphene/hydroxypropyl methylcellulose composite aerogels (RGA/HPMCs). Thanks to the rough surface and efficient photo-thermal conversion efficiency, the average light absorbance of RGA/HPMC can reach 90.4% in the entire solar spectral range, and the temperature of the upper surface of the aerogel can be rapidly heated to 88.3 °C within 40 s under 1 sun illumination, resulting in a significant reduction in the viscosity of the crude oil and an enhancement of the adsorption capacity for it, up to 124.43 g·g −1 within 22 min. In addition, the good mechanical properties of RGA/HPMC led to no obvious damage when subjected to 300 cyclic compression experiments under 70% strain. And after five times of adsorption-extrusion desorption, the adsorption capacity remained above 90% of the initial adsorption capacity, indicating that the aerogel has good reusability and broad application prospect in the field of offshore oil spill treatment. Graphical Abstract: ga1 Highlights: Graphene/hydroxypropyl methylcellulose composite aerogels were prepared by a two-step hydrothermal reduction combined with ice template method. The introduction of hydroxypropyl methylcellulose significantly enhanced the mechanical properties and thermal conductivity of aerogels, while also reducing the cost of aerogel preparation. The growth of ice crystals in all directions leads to numerous and dense pore structures in the aerogel, which can absorb crude oil 124.43 times its own mass. The aerogel can rapidly heat up to 88.3 °C within 40 s and transfer heat to the lower surface to achieve efficient adsorption of heavy oil.