We need the equation of the chemical reaction between carbon and H2O2. Moreover, the reaction may be incomplete (high probability) due to thermodynamic conditions (P, T, concentration). Therefore, only the theoretical mass of carbon to be used to remove H2O2 can be estimated using the equation of the chemical reaction cited above.
If you are thinking about activated carbon it actually destroys H2O2 catalytically which is the prefered industrial method to remove residual H2O2.
In this case the answer is that your needed amount depends on how fast you need the degradation to occur (degradation linearly depends on amount of catalyst). In terms of consumption of carbon it would be zero as the carbon isn't consumed by the reaction.
How many gram of carbon is needed to remove 200ppm of hydrogen peroxide h2o2 from 1m3 wastewater?. Available from: https://www.researchgate.net/post/how_many_gram_of_carbon_is_needed_to_remove_200ppm_of_hydrogen_peroxide_h2o2_from_1m3_wastewater [accessed May 7, 2017].