Elimination of arsenic (III) by adsorption on coal resulting from date pits and activated thermally and chemically

Abstract

The objective of this study is the valorisation of a lignocellulosic natural residue, date pits, and its application in the removal by adsorption of the arsenic (III) contained in water. The chronological stages in obtaining coal were: cleaning, drying, crushing and finally either a thermal treatment by pyrolysis at 900 W C (CAP1) or a chemical pretreatment with iron oxide of the natural residue followed by carbonisation at 600 W C (CAP2). The choice of iron oxide is based on the fact that arsenic (III) has strong affinities for the hydroxide and oxide of this metal. The characterisation of the carbonaceous matter showed properties comparable with those of many industrially produced coals. Retention tests of arsenic (III) on the two adsorption materials studied gave a maximum capacity of adsorption (at 20 W C and 24 h of contact time) of about 25 mg/g for the chemically activated carbon and 21 mg/g for the thermally activated one. The study of the influence of pH and temperature showed that at neutral pH and ambient temperature (T ¼ 20 W C), the optimal adsorption of arsenic (III) follows quite closely the Langmuir and Freundlich models. The kinetics of adsorption is slow and is of pseudo-second order type.

Valorization of raw biomaterial waste-date stones-for Cr (VI) adsorption in aqueous solution: Thermodynamics, kinetics and regeneration studies

“…At present, date stones are used mainly for animal feeds: sheep, camel, and poultry (Al-Ghouti et al, 2010). In Recent years, date pits have been used raw or treated (physically or chemically) for the removal of some heavy metals and organic pollutants from aqueous solution (Banat et al, 2003;Ziati et al, 2012;Al-Ghouti et al, 2013). To better understand the absorptive capacity of this biomaterial, several techniques were performed to characterize the D.S such as IR, SEM, XRD and BET surface area.…”

Laterite, Sandstone and Shale as Adsorbents for the Removal of Arsenic from Water

“…At pH greater than the PZC, adsorbent surface is negatively charged and arsenite adsorption decreases due to electrostatic repulsion. Similarly, maximum adsorption was observed for As (III) adsorption in the pH range 6 -7 on activated coals [20].…”

Valorization of lignocellulosic biomass into sustainable materials for adsorption and photocatalytic applications in water and air remediation

“…The production of carbon materials from lignocellulosic biomass wastes has gained attention in recent years, particularly due to its low cost and relative earth abundance (Ziati et al 2012;Yahya et al 2015;Ikram et al 2022). Lignocellulosic biomass mainly contains three components: lignin, cellulose, and hemicellulose, wherein lignin is the central part.…”