Estudio de diferentes activantes químicos en la obtención de carbón activado a partir de la cáscara de Hymenaea courbaril L. para la remoción de cadmio (Il)

The use of ZnCl₂ . H₃PO₄ H ₂S0₄. HNO₃ and HCl for algarrobo frult shell activatlon (Hymenaea courbaril L) permitted lo evaluate and compare tl1e adsorptive capacity of the corresponding carbons pre-pared. The precursor was impregnaled with the chemlcal agents mentioned. separately and it was pyrolized at 500°C in each case. The superficial characteri tics of lhe activated carbons pr par d were det rmined through the Brunnauer-Emmet-Teller (S _BET) conv ntional method. obtaining adsorption Iso therms of N ₂ at 77K and were compared to those of the Norit-A (CAC) commerclal actlvated carbono The balance determination at liquid phase of the process was carried out by llsing cadmium (II) solutions in load essays at initial concenlrations (Co) of 25. 50 and 100 mg/Lduring 1 h ontact time. The cadrnlum (II) balance concentration was determined by flame atomic adsorption spectrophotometry (EAA). The activatecl carbons with H3P04 and ZnCb presented specific superfi lal area values (SBET) of 1262 and 968 m²/ g. respectively. The Freundlich and Langmuir models were applled to the experimental results. The ls therms showed better adsorplion conditions at solu tions with a cadmium (II) CO of 25 mg/ L for all the carbons preparecl. The correlation coefficient values (R²) and the ad orptlon constant K_r for activaled carbon with H₃P0₄ fit Freundlich's moclel better.