Performance of novel MgS doped cellulose nanofibres for Cd(II) removal from industrial effluent – mechanism and optimization

Abstract

Green environment friendly and novel nano MgS decorated cellulose nanofibres (MgS@CNF) were prepared, characterized and evaluated towards the removal of heavy metal namely, cadmium from aqueous solutions. Cellulose nanofibres acted as a template for effective dispersion of MgS nanoparticles and also aid in the complexation of cadmium ions. In depth X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Fourier transform infra red spectroscopy (FTIR) studies revealed that doped MgS on mild acidification yields insitu production of H 2 S which effectively complexes cadmium ion to form cadmium sulfide. The reaction followed pseudo first order kinetics with regression coefficient in the order of 0.98. A very high Langmuir adsorption capacity in the order of 333.33 mg/g was obtained for MgS@CNF. Finally, MgS@CNF was applied towards the removal of cadmium from organic and TDS rich tannery waste water. MgS@CNF was effective in bringing down the concentration from ppm to ppb levels.

Synthesis and Water Treatment Applications of Nanofibers by Electrospinning

“…The pH changes showed that cadmium removal highly depends on solution pH, contributing to the complexing of Cd(II) and OH − groups of cellulose to form cadmium hydroxide. Increasing pH from 5 to 5.5 enhanced cadmium removal by 17%, and further increment decreased the adsorption by around 40% [108]. Ebrahimi et al (2019) [109] prepared PVA/SA nanofibers which exhibited higher Cd(II) adsorption capacity up to 163.9344 mg/g at 120 mg/L cadmium concentration.…”

“…Electrospinning was found to be the most versatile and straightforward method for the production of nanofibers by polymer solution with diameter ranges from hundreds of nanometers to microns [107]. Surface modification is done on electrospun fibers by doping, dispersion, crosslinking, and grafting with several compounds to enhance the adsorption capacity of nanofibers [108][109][110]. In this section, different types of nanofibers for heavy-metal removal are discussed.…”

“…In this section, different types of nanofibers for heavy-metal removal are discussed. Cellulose nanofibers are green and biodegradable, extracted from sugarcane bagasse, and doping of nano MgS enables development into a bio-nano composite fiber with increased capacity toward Cd(II) [108]. Chitosan (CS) nanofibers are environmentally friendly because of their biodegradability, nontoxicity in nature, biocompatibility, low price, and higher abundance in nature.…”

The CdIn2S4/WO3 Nanosheet Composite Has a Significantly Enhanced Photo‐electrochemical Cathodic Protection Performance and Excellent Electron Storage Capability

“…In the O 1s core level spectrum of the CdIn 2 S 4 /WO 3 photoelectrode shown in Figure 5C, the binding energy peak can be deconvoluted into three peaks at 530.8, 532.1 and 533.6 eV which belong to lattice oxygen W−O, O−H and H 2 O, respectively [19] . The Cd 3d XPS core level spectrum of the CdIn 2 S 4 /WO 3 photoelectrode is shown in Figure 5D, two binding energy peaks corresponding to Cd 3d 5/2 and Cd 3d 3/2 are observed at 405.5 and 412.3 eV respectively, indicating that the valence of Cd in the CdIn 2 S 4 /WO 3 photoelectrode is +2 [20] . In the In 3d core level spectrum of the CdIn 2 S 4 /WO 3 photoelectrode shown in Figure 5E, the binding energy peaks at 445.4 and 453.0 eV are assigned to In 3d 5/2 and In 3d 3/2 , respectively, indicating that In is existed as In 3+ in the CdIn 2 S 4 /WO 3 photoelectrode [21] .…”

Aqueous Adsorption of Heavy Metals on Metal Sulfide Nanomaterials: Synthesis and Application

“…These processes make the MSs capable of capturing hydrated HMs with hydrated radii larger than the layer d-spacing of MSs [8]. The affinities for metals are enhanced by enlarging the interlayer spacing, allowing for HMs sequestration via coordination [9,10], and ion exchange [11].…”