Equilibrium and Kinetic Study of Ammonium Sorption by Raphia farinifera

Abstract

The study investigated the sorption capacity of biosorbent-raphia sp. against ammonia. Raphia fibers were used without and with the modification of its surface with NaCl, NaNO 3 , and K 2 SO 4 . The data was analyzed in the state of equilibrium using four isotherm models such as Langmuir, Freudlich, Temkin, and Dubinin-Radushkevich. The equilibrium of ammonia sorption for all studied systems was best described by the Freudlich isotherm model. On its basis, it can be assumed that the studied process is of chemical nature, which results from the value of the coefficient 1/n < 1. In order to confirm the sorption mechanism, analysis of the kinetics of the ammonia sorption process on raphia fibers was performed. Four kinetic models of sorption were calculated: pseudo-first-order model, pseudosecond-order model, Elovich model, and Webber-Morris intermolecular diffusion model. The sorption kinetics of the modeled ammonia waste were carried out using unmodified palm fibers and all kinds of surface modification. This process was best described by the pseudo-second-order sorption model, which can be considered as a confirmation of the chemical nature of ammonia sorption on raphia sp. fibers.

Raphia-Microorganism Composite Biosorbent for Lead Ion Removal from Aqueous Solutions

“…Raphia (Raphia farinifera ) fibers, whose main components are cellulose, hemicellulose, and lignin, was used as the carrier. Raphia fibers have been successfully used as a biosorbent to remove ammonia and methylene blue, confirming its ability to remove pollutants from the aquatic environment [ 22 , 23 ]. The biomass used was the yeast Saccharomyces cerevisiae , which is one of the most common microorganisms available in large quantities as a by-product of fermentation processes or the pharmaceutical industry.…”