conversion of waste corn cob to highly green surface activated carbon: removal and adsorptive of copper ions from aqueous solution

In the study, corn cob is activated carbon (ac) by treating it with h3po4 to obtain a constant weight of activated carbon corn cob (ac-cc). the ac-cc characterized via sem, edx, and tem. copper ions were removed from an aqueous solution utilizing ac-cc. the surface before the adsorption process contains irregular gaps and stomata, which create many active sites on the surface where the acid works to prepare active sites capable of adsorption, but the surface after adsorption displays very clear distinct black spots that confirm the high adsorption of copper ions into the pores and cavity of the adsorbent. the tem image for ac-sfs appears from the bulk background color attributed to the ac resulting from the acid activation process and edx patterns of ac-cc, which verified the presence of carbon and oxygen groups and also phosphorus resulting from surface activation by phosphoric acid. the best isotherm analysis was performed via isotherm langmuir and freundlich models. the data showed that the removal of cu (ii) via ac-cc carefully applies to the freundlich model with a (r2 =0.9593), and also the maximum removal adsorption is 92.44 % and adsorption capacity is 53.56 mg/g. these data showed that the utilizing of corn cob as activated carbon to remove copper ions would be an interesting option as cost-effective and eco-friendly.