Preparation of an Activated Carbon Composite with High Thermal Conductivity Based on Emulsified Asphalt and Carbon Nanotubes and its Adsorption Performance for n-Hexane

Graphical The preparation process of composite activated carbon is mainly from stirring, then high temperature sintering to carbon, followed by a large amount of water washing to remove impurities, and finally drying to obtain composite activated carbon. During the high temperature sintering, asphalt is carbonized to form fluffy carbon material, which increases a lot of space for the loading of CNTs. Activated carbon, as the main adsorption material for treating VOCs, has been widely used. To solve the problem of safety hazards in activated carbon adsorption process due to the large amount of heat released, highly thermally conductive composite activated carbon (A-AC/CNTs) was prepared using asphalt and highly thermally conductive carbon nanotubes (CNTs) for thermal conductivity improvement. Uniform dispersion and firm loading of CNTs in the carbon production material were achieved by dispersing carbon nanotubes (CNTs) in the asphalt-in-water emulsion. Experimental results showed that the specific surface area of A-AC/CNTs reached a maximum when the loading of CNTs was 0.5 wt %. Meanwhile, the thermal conductivity increased by 1.5 times compared with the original activated carbon. The adsorption capacity of n -hexane reached the maximum of 2868 mmol ⋅ g −1 , and the adsorption capacity increased by 21.41 %. It also maintained good regeneration performance after dynamic adsorption experiments.