Mixing acid with biomass during the preparation of activated carbon is important because the acid helps to remove impurities in the raw material, such as lignin and hemicellulose. The acid also helps to increase the surface area of the activated carbon, which increases its adsorptive capacity. In addition, the acid helps to create a more uniform pore size distribution throughout the activated carbon, which in turn increases its adsorptive capacity. Finally, the acid also helps to improve the mechanical strength of the activated carbon, which increases its durability.

That said, regarding

What are the possible benefits of impregnating biomass with acid/base?

How could it enhance the formation of pores?

What will be its effect on the carbon content of biomass?

I think the possible benefits of impregnating biomass with acid/base include increased porosity, improved reactivity, and increased surface area. Impregnation with acid/base increases the porosity of biomass by creating more pores and increasing their size. This improves the reactivity of the biomass by increasing surface area, which facilitates faster and more efficient reactions. Additionally, the impregnation process can also reduce the carbon content of the biomass due to the acid/base reaction with the carbon. This can improve the combustion characteristics of the biomass, as it will burn more efficiently and completely.

It enhances the activity of the catalyst (increase in acidity of catalyst) by attaching functional group to the carbon access material.

Otherwise biomass itself is not functional/ less reactive