Rational modification of chitosan biopolymer for remediation of Cr(VI) from water

Efficient removal of Cr(VI) contaminant using recoverable silica from volcanic ash as natural adsorbent: Synthesis and activity in the mechanism and kinetic adsorption

“…Meanwhile, in the solution at pH lower than 3, Cr(VI) are formed as HCrO 4 − and low fraction of CrO 4 2− allowing them to have weak affinity with the adsorbent surface. With the increase of up to 3, the species of CrO 4 2− and Cr 2 O 7 2− are formed serving the conductive adsorption through electrostatic interaction with protonated nitrogen from CTA-Br [ 1 , 6 ]. At pH higher than 4, the gradual adsorption decrease is observable, where the negative charges of both adsorbent surface and the adsorbate were available repulsing them to mutually interact.…”

“… Mg–Zn ferrite Sol-gel 30.5 – Langmuir [ 15 ] 9. Thiolated chitosan Microwave irradiation 340.1 Pseudo-second order Freudlich [ 1 ] 10. MnFe 2 O 4 @SiO 2- CTA-Br Hydrothermal 24.0 Pseudo-second order Freudlich [ 37 ] 11.…”

“…Chromium element is found in two forms that are trivalent Cr(III) and hexavalent chromium Cr(VI) with very different properties. Trivalent chromium, Cr(III) in the aqueous solution exists as cationic form that is useful for maintaining the glucose concentration in human body [ 1 ] while Cr(VI) is found as anionic with high toxicity [ 2 ]. Therefore, the environmental contamination by Cr(VI) anion has become a major concern in around the world.…”

Biosorption behavior of acid orange 7 dye onto Cucumis sativus peel biochar and its effect on growth of Triticum aestivum

“…13,14 Adsorption is used as top quality treatment procedures for the removal of dissolved organic pollutants like dyes from industrial waste water. [15][16][17][18][19][20][21][22] Recent studies have focused on the biochar application for elimination of contaminants from aqueous medium due to their better performance over activated carbon. 23 The biochar is a highly porous, durable, rich in carbon which is generated through the pyrolysis of waste biomass rich in cellulose, hemicellulose, and lignin under low-oxic or anoxic conditions.…”

“…Agro‐wastes like wheat and paddy straw, spent tea leaves, mango seed husks, walnut and cashew shells and banana and orange peels, Moringa stenopetala seed extract, food waste have been applied in carbon materials generation that can remove contaminants from wastewater 13,14 . Adsorption is used as top quality treatment procedures for the removal of dissolved organic pollutants like dyes from industrial waste water 15–22 . Recent studies have focused on the biochar application for elimination of contaminants from aqueous medium due to their better performance over activated carbon 23 .…”