Application of polypyrrole-based adsorbents in the removal of fluoride: a review

Abstract

When fluoride levels in water exceed permitted limits (>1.5 mg L−1), water pollution becomes a major concern to humans.

Oxidative Polymerization of Aniline on the Surface of Sisal Fibers (SFs) as Defluoridation Media for Groundwater

“…Maximum defluoridation of fluoride was achieved at pH 5 (pH < pHpzc = 6.08) where the surface charge of the adsorbents remained positive [ 34 ]. At extreme acidity, the amount of fluoride uptake was reduced due to the formation of weak fluoro acids and complex species (HF, HF 2 − , and F − ) which can affect the accessibility and mode of interaction of fluoride [ 32 ].…”

“…Protonation of nitrogen due to polymerization of aniline enhanced the electrostatic interactions between amine and imine surfaces with fuoride ions in aqueous solution. Furthermore, fuoride ions can easily displace a highly polarizable chloride ion which exists on the surface and interface of polyaniline as a counter anion [32]. Te fuoride uptake capacity increased steadily (up to 2.21 mg/g) when the solution pH began to rise up from 1 to 4.…”

Supercapacitores: Revisão

“…Durante o processo de dopagem, o polímero sofre oxidação e perde um elétron da cadeia neutra, o que acarreta na alteração de sua estrutura aromática para a forma quinoide (Figura 13D,E). Assim, a condução do polímero nesse estado dá-se via pólarons e bipólarons (Pang et al, 2020, Stejskal & Trhová, 2018, Ashassi-Sorkhabi & Kazempour, 2020, Wang et al, 2022. Fonte: Adaptada de Wang et al, (2018).…”

Adsorptive avidity of Prussian blue polypyrrole nanocomposite for elimination of water contaminants: a case study of malachite green and isoniazid

“…15 Here, polypyrrole (PPY) was chosen as a porous conducting polymer as its adsorbents have shown high adsorption capacity and selectivity for a variety of dyes and contaminants due to chemisorption and electrostatic interactions. [16][17][18] However, the impact of transition metal complex doping on polymers for adsorption applications has been scarcely studied. In continuation of our interests in applications of transition metal complexes, [19][20][21] especially as dopants in conducting polymer matrix for dielectric properties and water treatment applications, 22,23 we explore here their structure-activity response for the adsorption of dye and antibiotic contaminants under environmentally viable conditions (pH 7, and 20 1C).…”