Highly efficient biosorbent produced from Syagrus romanzoffiana to be applied in water treatment

Abstract

A new adsorbent from Jerivá coconut (a native fruit of the Atlantic Forest) was developed through thermal activation at high temperatures and chemical activation using H3PO4. The characterization of activated carbon revealed the functional groups O-H, NH2 and C=C. The morphology showed an irregular and heterogeneous surface, with a pore volume of 0.442 cm3 g−1 and a surface area of 750 m2 g−1. The main variables of the process were evaluated for statistical significance in the removal of the methylene blue dye showing that only the agitation of the system affected the process. Adsorption kinetics were performed at three different concentrations and fitted to nonlinear models where the Avrami-fractional-order model represented the experimental data. Equilibrium occurred within 80 min and was sufficient to remove more than 99% of the initial concentration. The sorption isotherms were performed at four different temperatures, fitted to four nonlinear models. The Sips model obtained the best adjustment, with a maximum adsorption capacity of 254.40 mg g−1, for the highest temperature investigated. The process occurred spontaneously, favorably and endothermically. The results were promising, pointing out that this adsorbent has the potential to remove methylene blue and the treated effluent can be reused for less noble purposes in the industry.

Comparative Evaluation of the Adsorption Performance of Citric Acid-Treated Peels of Trapa natans and Citrullus lanatus for Cationic Dyes Degradation from Water

“…e pH of the dye adsorption on lignocellulose substrates was adjusted using 0.1 M NaOH or 0.1 M HCl solutions during the experimental work [50].…”