Removal of Co by carbonaceous material obtained through solution combustion of tamarind shell

ABSTRACT

New carbonaceous materials were obtained through solution combustion process of tamarind shell in the presence of urea and ammonium nitrate, and all of them were tested for Co removal. The effect of temperature (from 600 to 1000°C) and water volume on surface texture of carbonaceous material and its adsorptive capacity was evaluated. Scanning electron microscope, Fourier transform infrared spectroscopy, X-ray powder diffraction, and Brunauer–Emmett–Teller (BET) model were used to characterize the obtained carbonaceous material before applying for the removal of cobalt. The point of zero charge was also determined. The results indicate that BET-specific surface areas ranged from 6.40 to 216.72 m²g⁻¹ for the carbonaceous materials obtained at 600, 700, 800, 900, and 1000°C. The one obtained at 900°C (CombTSF₉₀₀) was found to be the most effective adsorbent for the removal of Co(II) ions from aqueous solutions, with a maximum sorption capacity (Q_max) of 43.56 mg/g. Carbonaceous material obtained through the solution combustion process improves morphological characteristics of adsorbent in a short time, and could be used as an alternative method for the removal of cobalt.

KEYWORDS:

• tamarind shell
• solution combustion process
• cobalt

Acknowledgment

The authors acknowledge the financial support provided by CONACyT (project 254665).

Supporting information

Supporting information (SI) contains the SEM images of the FTS and carbonaceous materials (CombFTS samples) including the CombFTS₉₀₀ after the Co sorption (Figures S1–S3); the X-ray diffraction patterns of TS, FTS, and the carbonaceous materials obtained at different temperatures (Figure S4); the IR spectra of all the carbonaceous materials (Figure S5a–d); and the N₂ adsorption-desorption isotherms corresponding to each carbonaceous samples (Figure S6a and b).