Asphaltene precipitation is a common phenomenon in the exploitation of crude oil and closely correlates with oil recovery, especially in CO2 flooding. In this work, employing molecular dynamics simulations, the asphaltene precipitation process in CO2 was investigated. The simulation results reveal that the CO2 could stepwise extract nonpolar and light polar components from asphaltene micelle, and a two-step asphaltene precipitation process was illustrated. In our eight molecule asphaltene system, first four asphaltene dimers formed. Two dimers get together into one aggregation in bulk; the other two dimers get together and adsorbed onto the silica surface. After that, the surface aggregation further induces the adsorption of bulk aggregation onto it to complete asphaltene precipitation. In addition, we also studied the pressure effect on asphaltene precipitation. Our work provided a molecular-level understanding of asphaltene precipitation phenomenon in CO2 flooding, and the results have significant promise for oil exploitation.

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Aqueous zinc-based batteries are promising candidates for the grid-scale energy storage owing to their nonflammability, ecofriendliness, and low cost. Nevertheless, their practical applications are hindered by the relatively low capacity and energy density. Herein, we develop a quasi-solid-state aqueous zinc–dual halogen battery composed of freestanding carbon cloth–iodine cathode and in situ prepared concentrated aqueous gel electrolyte. The freestanding composite cathode and aqueous gel electrolyte can afford iodine source and bromide ions, respectively, thus activating the I–/I0/I+ reaction by forming [IBr2]− interhalogen. Furthermore, the conversion reaction of Br–/Br0 in [IBr2]− interhalogen is stimulated due to the catalytic effect of iodine. Therefore, this rationally designed aqueous dual halogen conversion chemistry enables three successive redox reactions (i.e., I–/I0, I0/I+, and Br–/Br0). Additionally, the LiNO3 additive and acrylamide (AM)-based polymer matrix not only stabilizes the anode/electrolyte interface but also restrains the side reactions and dissolution/diffusion of active species. Consequently, the as-assembled aqueous zinc–dual halogen battery exhibits high areal capacity and energy density.

Preparing nanoporous membranes with high density and ordered pore sizes which allows high water permeability and salt rejection rate is the key to realize highly efficient desalination. However, Preparing nanoporous...