[01] Chrisdel Chancelice NDJEUMI, Laboratoire des Matériaux et Chimie Industrielle Inorganique, ENSAI – University of Ngaoundere, Ngaoundere, Cameroon; Department of Chemical Engineering, Babeș-Bolyai University, Cluj-Napoca, Romania; Department of Environmental Sciences, ISS – University of Maroua, Maroua, Cameroon. [02] Andrada MĂICĂNEANU, Department of Chemical Engineering, Babeș-Bolyai University, Cluj-Napoca, Romania. [03] Jean Baptiste BIKE MBAH, Laboratoire des Matériaux et Chimie Industrielle Inorganique, ENSAI – University of Ngaoundere, Ngaoundere, Cameroon. [04] Ghislain Arnaud MOUTHE ANOMBOGO, Laboratoire des Matériaux et Chimie Industrielle Inorganique, ENSAI – University of Ngaoundere, Ngaoundere, Cameroon; Department of Chemical Engineering, Babeș-Bolyai University, Cluj-Napoca, Romania; Department of Environmental Sciences, ISS – University of Maroua, Maroua, Cameroon. [05] Richard KAMGA, Laboratoire des Matériaux et Chimie Industrielle Inorganique, ENSAI – University of Ngaoundere, Ngaoundere, Cameroon.

The purpose of this study was to investigate the potential use of alumina as adsorbent for humic acids removal from water. The main parameters that influence the adsorption of humic acids were highlighted by means of an experimental design based on Hadamard matrix. It was found that pH is the most important physico-chemical parameter, while particle size and porosity are the main adsorbent property that influences the adsorption efficiency. The optimum conditions to remove 99% of humic acids from solution at 25ºC are: pH 6.0, alumina particle size < 100 μm and pore size of about 15.9 nm. The kinetic modelling of experimental data showed that the process is better described by the pseudo-second-order kinetic model.

Humic Acids, Adsorption, Experiment Design, Alumina, Kinetic Modelling

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