Decontamination of Sr(II) on Magnetic Polyaniline/Graphene Oxide Composites: Evidence from Experimental, Spectroscopic, and Modeling Investigation

Abstract

The interaction of Sr­(II) on magnetic polyaniline/graphene oxide (PANI/GO) composites was elucidated by batch, EXAFS, and surface complexation modeling techniques. The batch experiments showed that decreased uptake of Sr­(II) on magnetic PANI/GO composites was observed with increasing ionic strength at pH <5.0, whereas no effect of ionic strength on Sr­(II) uptake was shown at pH >5.0. The maximum uptake capacity of magnetic PANI/GO composites derived from the Langmuir model at pH 3.0 and 293 K was 37.17 mg/g. The outer-sphere surface complexation controlled the uptake of Sr­(II) on magnetic PANI/GO composites at pH 3.0 due to the similarity to the EXAFS spectra of Sr2+ in aqueous solutions, but the Sr­(II) uptake at pH 7.0 was inner sphere complexation owing to the occurrence of the Sr–C shell. According to the analysis of surface complexation modeling, uptake of Sr­(II) on magnetic PANI/GO composites was well simulated using a diffuse layer model with an outer-sphere complex (SOHSr2+ species) and two inner-sphere complexes (i.e., (SO)2Sr­(OH)− and SOSr+ species). These findings are crucial for the potential application of magnetic nanomaterials as a promising candidate for the uptake of radionuclides for environmental remediation.

Removal of Sr(II) in Aqueous Solutions Using Magnetic Crayfish Shell Biochar

“…Its chemical structure is similar to Ca(II) [1], and it can protect the human heart against myocardial ischemia/reperfusion injury and prevent arteriosclerosis and thrombosis [2]. At the same time, Sr-90 is also one of the most abundant radionuclides in the cooling water of nuclear power plants, with a half-life lasting as long as 29 years [3]. After being absorbed by human body, Sr is easily accumulated in the liver, lungs and kidneys [4], damaging the genetic material in cells and leading to bone cancer and nervous system diseases [5,6].…”

Targeted nanoparticle binding & detection in petroleum hydrocarbon impacted porous media

“…Soil remediation using materials designed for targeted removal of specific contaminants has been a subject well studied in the area of toxic metals removal wherein the mobile contaminant species is adsorbed to a high-surface area nanostructure such as titanate nanotubes or modified graphene oxide (Chang et al, 2017a;Hu et al, 2017aHu et al, , 2017cLinghu et al, 2017). Some graphene oxide-based strategies introduce the possibility of target contaminant immobilization by forming graphene oxidemetal ion complexes with enhanced adsorption to mineral material (Chang et al, 2017b;Hu et al, 2017b;Sheng et al, 2018).…”

Cosorption Characteristics of SeO42– and Sr2+ Radioactive Surrogates Using 2D/2D Graphene Oxide-Layered Double Hydroxide Nanocomposites

“…Removal of radioactive nuclides using pure GO has also been studied extensively. − The nanosheets of GO tend to disperse in water, which makes them difficult to separate from the medium after remediation. , The dispersed GO nanosheets released in the aqueous environment cause secondary water pollution, leading to biotoxicity to living organisms. , To reduce the bioavailability and to enhance the sorption efficiency, GO nanosheets are fabricated with different types of support and tremendously utilized for the removal of Sr 2+ . For instance, composite materials, such as magnetic polyaniline/GO, polyacrylamide-GO, ethylene diamine tetra-acetic acid-functionalized-GO, thiacalixarene-functionalized-GO, magnetite-GO, WO 3 -GO, and GO-bayberry tannin sponge have been prepared and utilized for the removal of Sr 2+ . Besides the prevention of GO nanosheet release, the solid supports could provide some additional functionality to target another pollutant in the composite materials and thus are highly encouraged.…”

“…14,15 To reduce the bioavailability and to enhance the sorption efficiency, GO nanosheets are fabricated with different types of support and tremendously utilized for the removal of Sr 2+ . For instance, composite materials, such as magnetic polyaniline/GO, 16 polyacrylamide-GO, 17 ethylene diamine tetra-acetic acid-functionalized-GO, 18 thiacalixarenefunctionalized-GO, 19 magnetite-GO, 20 WO 3 -GO, 21 and GObayberry tannin sponge 22 have been prepared and utilized for the removal of Sr 2+ . Besides the prevention of GO nanosheet release, the solid supports could provide some additional functionality to target another pollutant in the composite materials and thus are highly encouraged.…”