The use of ZnCl2 activation to prepare low-cost porous carbons coated on glass fibers using mixtures of Novolac, polyethylene glycol and furfural as carbon precursors

Using ZnCl2 as an activation agent, low-cost porous carbons were prepared using mixtures of Novolac, polyethylene glycol (PEG) and furfural in alcohol as carbon precursors that were coated onto glass fiber mats. The morphology, microcrystalline structure, pore structure, surface chemistry, mechanical strength and adsorption properties of the porous carbons were characterized. Results show that the addition of furfural and PEG to the carbon precursors greatly improves pore development. The specific surface area of the porous carbons is as high as 2023 m2/g when PEG and furfural are added, otherwise it is only 404 m2/g. It is found that the addition of PEG to the precursors can increase the solubility of ZnCl2 in alcohol, and thus facilitate the activation of the carbon precursors. The formation of a crosslinked structure of furfural with Novolac is responsible for the improvement in the thermal stability of the precursors and the increase in the carbon yield, which favors the increase in the surface area and the reduction of the production cost. The porous carbons have similar adsorption performance and microcrystalline structure to conventional activated carbon fibers.