Title:Removal of Various Pollutants from Wastewater Using Plasma-Modified Lignocellulose-Derived as a Low-Cost Adsorbent: An Overview
Volume: 18
Issue: 4
Author(s): Elie Acayanka*, Jean-Baptiste Tarkwa, Brice Takam, Daouda Abia, Nzali Serge, Georges Y. Kamgang and Samuel Laminsi
Affiliation:
- Laboratoire de Chimie Physique et Analytique Appliquee, Departement de Chimie Inorganique, Universite de Yaounde I, P.O. Box: 812 Yaounde,Cameroon
Keywords:
Non-thermal plasma, acidifier, plasma-activated materials, plasma-surface treatment, heavy metals, dyes products
pollutants removal.
Abstract: In their search for an alternative to commercial adsorbents, much research is turned to the
local biomass-based materials such as agricultural residues and assimilated derivatives. However,
natural biomass due to its low specific surface area must first undergo several pre-treatments. Among
the newly emerging electric techniques for environmental applications, those who operate at atmospheric
pressure (Non-thermal plasma) have recently found many breakthrough applications arising
from their easy use with no extra additional reagents and their high reactivity. The Non-thermal
plasma treatment of biomass is one of the promising developed approaches mainly due to significant
effects including the formation of micro and macrospores, the increase of surface roughness, and surface
functionalization. The most used plasma is non-thermal, so as not to denature the biomass,
likewise the hot plasma can burn and/or destroy high contains carbon biomaterials. Especially, the
gliding arc plasma obtained using moisten air as feeding gas, which is known to induce acidifying
and oxidizing effects in an aqueous target. The primary species HO• radicals [E° (HO•/H2O) = 2.85
V/SHE] mainly formed in the arc will be with the dimer H2O2 [E°(H2O2/H2O) = 1.76 V/SHE] the determining
agents for the chemical reactions induced. Exposure of a target to this kind of environment
is likely to promote great surface transformations. This approach has some advantages: (i) the merit
of not using commercial chemical reagents, the reactive species being in situ generated; (ii) the risks
related to the manipulation of the products, the plasma reactor is robust and can be modulated to treat
large quantity; (iii) the efficiency of the bi-functionality of the plasma (acidifier and oxidative). In
this review, we will highlight the main changes induced by exposure of biomass to plasma treatment
and also make a comparative study between chemically and plasma-activated materials in the
removal of various pollutants from aqueous solution; and finally, we summarize the findings in the
existing literature.
