Design, characterization, and adsorption properties of Padina gymnospora/zeolite nanocomposite for Congo red dye removal from wastewater

Abstract

A comprehensive study combined experimental, computational and field experiments was conducted to find out the most appropriate adsorbent system for industrial elimination of congo red (CR) dye from simulated industrial wastewater. Modification of the zeolite (Z) by the Padina gymnospora algae (PG) (Egyptian marine algae) was evaluated in terms of the adsorption capability of the zeolite (Z) to remove CR dye from aqueous solutions. The zeolite/algae composite (ZPG) was fabricated using the wet impregnation technique. Various techniques were used to characterize the PG, Z, and the produced ZPG nanocomposite. Batch experiments were performed to study the influence of various practical variables on adsorption processes. The isotherms and kinetics of dye adsorption were also studied. The newly synthesized ZPG nanocomposite exhibits much higher adsorption capacity, especially at low CR concentrations than that of Z. The computational calculations have shown that owing to the presence of intermolecular interactions, the adsorption of the CR molecule on zeolite surfaces is exothermic, energetically favorable, and spontaneous. For all configurations, increasing the zeolite size does not have a noticeable impact on the adsorption energies. The experimental results revealed that the ZPG nanocomposite can be applied as an economical nanoadsorbent to eliminate anionic dyes from simulated industrial wastewater at low CR dye concentrations. The adsorption isotherm of dye onto Z, PG, and ZPG almost agreed with Langmuir isotherm and pseudo-second-order kinetics. The sorption mechanism was also evaluated using Weber's intra-particle diffusion module. Finally, the field experiments revealed optimistic results for the newly synthesized adsorbent in removing dyes from industrial wastewater with 82.1% efficiency, which in turn confirmed the foundation of new eco-friendly materials that aid in the reuse of industrial wastewater.

Experimental modelling studies on the removal of dyes and heavy metal ions using ZnFe2O4 nanoparticles

“…Environmental pollution created by the disposal of dyes and heavy metals has become one of the major global concerns, threatening the ecosystem organisms and human health 1 , 2 . Over the past few decades, the growing use of dyes and heavy metals has led to the increase of these compounds in groundwaters and surface waters, which caused severe health and ecological hazards.…”

Activated carbon derived from sugarcane and modified with natural zeolite for efficient adsorption of methylene blue dye: experimentally and theoretically approaches

“…After the tenth run, the adsorption activity of the AC500/NZ was reduced from ~ 99.2 % at the first cycle to 95 % at the tenth cycle. The drop in MB removal% could be attributed to the agglomeration of MB molecules on the surface of the AC500/NZ adsorbent, which shields the adsorbent surface and pores from dissolved MB molecules, resulting in a decrease in adsorption capacity [69]. The result revealed a high performance until 10 consecutive runs with excellent efficiency.…”

Statistical optimization of process parameters for ultrafast uptake of anionic azo dyes by efficient sorbent: Zn/Cu layered double hydroxide

“…The shift in hydroxide bands toward lower wavenumber, that is, from 3407 to 3380 cm À1 , can be ascribed to the Hbonding between hydroxyl groups of Zn/Cu LDH and nitrogen/oxygen-containing groups of dye. Furthermore, the decrease in intensity of the strong absorption band of acetate ions was observed, which may be due to the pTSA-Pani@GO-CNT -26.8 300 5 [40] Chitosan hydrogel beads impregnated with CNT -450.4 360 5 [41] ILNO-NH 2 97 43.10 30 4 [42] Zeolite/algae composite (ZPG) 78.89 11.26 480 7 [43] Fly ash -22.12 180 Natural pH of dye [3] Cashew net shell 98.52 5.184 120 2 [44] Cu-Ca-Al-LDH/gellan gum nanocomposite -100 60 5 [45] Acetate intercalated Zn/Cu LDH >99 167.22 4 7 Present work…”