Assessment of banana rachis biochar as an adsorbent for arsenic in aqueous solutions

Arsenic contamination of water is an environmental and public health problem in the world. The objective of this research is to determine the adsorptive capacity of activated banana rachis biochar in the removal of arsenic in aqueous solutions. Four treatments (5, 10, 15 and 20 grams) and a control were applied in relation to the contact time (1, 2 and 3 hours) at initial pH 3. The biochar was characterized morphologically and structurally using scanning electron microscopy. In addition, the percentage of arsenic adsorption was calculated and the Langmuir and Freundlich isotherms were used to determine the adsorption behavior of the biochar. The results show that using 15 grams of biochar in a shorter time (1 hour) gives adsorption percentage results of 95.14 %. Electron microscopy showed an improvement in the porous structure of biochar after activation. The isotherms indicated that both models fitted better to the treatment with 15 grams of biochar (R2= 0.9989). In conclusion, activated banana rachis biochar is an efficient, economical and sustainable alternative for the removal of arsenic in aqueous solutions, taking advantage of agro-industrial wastes to contribute to the mitigation of environmental impacts.