Reusable Nanocomposite Membranes for Highly Efficient Arsenite and Arsenate Dual Removal from Water

Abstract

Nanocomposite membranes (NCMs) of poly(vinylidene fluoride‐hexafluoropropylene), PVDF‐HFP, with different yttrium carbonate and magnetite loadings, are prepared, and their dual adsorption capacity over neutral arsenite and anionic arsenate species is evaluated. The nanoparticles (NPs) and the corresponding NCMs are fully characterized in morphology, microstructure, thermal, and surface properties. The nanocomposite membranes present a micrometric porous structure with a homogeneous distribution of the active nanoparticles. Chemical, thermal, and water‐contact angle characteristics of the NCMs point out that they maintain the chemical and thermal stability of the polymer while improving the wettability. Arsenic removal depends on NP loading and pH of the media. For instance, efficiencies close to 100% are achieved for arsenate species under acidic conditions, while adsorption capacity over arsenite is also incremented above 80%. Fe3O4/PVDF‐HFP nanocomposite shows a dual affinity for the adsorption of As(III) and As(V) species, with the maximum adsorption capacities of 92.82 and 137.08 mg g−1, respectively. In addition, both NCMs are easily activated and reused without significant efficiency loss. Consequently, the nanocomposite membranes represent low‐cost, reusable, and efficient water remediation systems suitable for the long‐term removal of As(III) and As(V) under conditions mimicking real polluted surface and groundwater.

Smart and Multifunctional Materials Based on Electroactive Poly(vinylidene fluoride): Recent Advances and Opportunities in Sensors, Actuators, Energy, Environmental, and Biomedical Applications

“…A novel microporous structure based on Fe 3 O 4 / poly(VDF-co-HFP) and Y 2 (CO 3 ) 3 /poly(VDF-co-HFP) composites has been produced to remove As(V) and As(III) species from contaminated waters. 562 The results indicate adsorption capacities around 93 mg•g −1 for As(III) and 137 mg•g −1 for As(V) removal employing the Fe 3 O 4 /poly(VDF-co-HFP) membrane. Additionally, this work contemplated reusability tests that resulted in an efficiency loss of 13% of the Fe 3 O 4 /poly(VDF-co-HFP) nanocomposite membrane and increased efficiency by around 6% with the yttrium carbonate 586 This membrane is particularly interesting because it combines two processes to produce porous structures: salt leaching and TIPS.…”

“…The As adsorption assays reveal that using a bayrite/As ratio of 200/1 there was a rejection of ∼60% (40% of As removal) of As species present in the solution after 1 h of operation (Figure c). A novel microporous structure based on Fe 3 O 4 /poly­(VDF- co -HFP) and Y 2 (CO 3 ) 3 /poly­(VDF- co -HFP) composites has been produced to remove As­(V) and As­(III) species from contaminated waters . The results indicate adsorption capacities around 93 mg·g –1 for As­(III) and 137 mg·g –1 for As­(V) removal employing the Fe 3 O 4 /poly­(VDF- co -HFP) membrane.…”

A State-of-the-Art of Metal-Organic Frameworks for Chromium Photoreduction vs. Photocatalytic Water Remediation

“…This point has been carefully studied when integrating the MOFs as surface thin films for gas membrane separation, or is in place to integrate the MOF properly in electronic devices or signal-transducer materials [ 298 , 299 , 300 ]. For instance, self-assembly [ 301 , 302 ], printing [ 303 ], deposition and patterning of MOFs [ 304 ] can play a key role to endow them with photonic properties to adsorb specific wavelengths [ 305 , 306 , 307 , 308 , 309 , 310 , 311 ]. In addition, the heterojunctions at this thin-film scale have been revealed to be beneficial for photocatalytic purposes as well.…”

On The Multiscale Structure and Morphology of PVDF‐HFP@MOF Membranes in The Scope of Water Remediation Applications

“…The integration of nanomaterials, and in particular of MOFs, into the polymeric porous structure of the PVDF-HFP represents a suitable strategy to improve the overall properties and functionality of the membranes based on this per-fluorinated polymer. [32,33] Among the different processing routes to prepare composites based on PVDF-HFP, phase separation is one of the most appropriate to obtain membranes with a well-interconnected porosity network suitable for water remediation. It involves the transition from a solution of the polymer in an organic solvent to the porous interconnected membranes based on PVDF-HFP.…”

“…The integration of nanomaterials, and in particular of MOFs, into the polymeric porous structure of the PVDF‐HFP represents a suitable strategy to improve the overall properties and functionality of the membranes based on this per‐fluorinated polymer. [ 32,33 ]…”