Ultrasound‐aided rapid and enhanced adsorption of anionic dyes from binary dye matrix onto novel hematite/polyaniline nanocomposite: Response surface methodology optimization

Abstract

In recent times, polyaniline (PANI), a conducting polymer, has been studied widely for environmental remediation application due to its controllable electric conductivity with high surface area, which makes it a suitable adsorbent material. But lower mechanical stability of PANI is considered to be a serious drawback for its large‐scale industrial application. To improve the mechanical strength of PANI, in this study, hematite nanoparticles were impregnated onto PANI by oxidative polymerization method in order to fabricate a novel organometallic nanocomposite (hematite‐PANI‐NC). The hematite‐PANI‐NC was used as adsorbent for removal of methyl orange (MO) and eosin yellow (EY) dye from binary dye matrix under ultrasonic‐assisted adsorption. Excellent MO and EY dye removal (more than 98%) was observed from binary matrix at a wide solution pH from 2.0 to 6.0, and under ultrasound wave the adsorption equilibrium was achieved within 15 min only. Both MO and EY dyes adsorption experimental data strictly followed Langmuir isotherm, and maximum monolayer adsorption capacity of 126.58 mg/g and 112.36 mg/g was observed for MO and EY dye, respectively. The uptake mechanism of MO and EY dyes onto hematite‐PANI‐NC is governed by electrostatic interaction, π‐π bonding and hydrogen bonding between dye molecules and nanocomposite. Response surface methodology analysis reveals maximum MO and EY removal of 98.43% and 99.35% at optimum experimental conditions. This study implies that the hybrid organometallic material hematite‐PANI‐NC has high potential for quick and enhanced sono‐assisted uptake of anionic dyes from water near neutral solution pH.

Adsorption and reduction of carcinogenic organics by ordered semi-crystalline poly-m-chloroaniline

“…Electron withdrawing substituted polyaniline will give positive character to the substituted PANI; as a result, this will interact with anionic dyes more than cationic dyes via electrostatic interaction and gets adsorbed on the surface of polymer. [28][29][30][31][32] There are many reports of polyaniline (PANI) to be good adsorbent for dye removal in comparison to poly(pyrrole) and poly (thiophene), [19][20][21][22] but as per our knowledge, there is no such report on absorption studies on poly-m-chloroaniline has been studied. In this paper, poly-m-chloroaniline has been synthesized by chemical oxidation using H 2 O 2 as an oxidizing agent and FeCl 2 used as a metal to provide ordering in the structure.…”

Competitive adsorption and mechanism of hexahydroxy metallic system by aminated solution-blown polyacrylonitrile micro/nanofibers

“…This kind of adsorbent has a high surface area because of the nano-scale diameter of the polymer nanofibers, and surface groups can be changed by choosing different polymers or modification. It can satisfy the criterion of a material used for adsorption (Saeed et al 2008;Kampalanonwat & Supaphol 2010;Neghlani et al 2011;Huang et al 2013;Deb et al 2020aDeb et al , 2020b. There has been substantial interest in surface modifying PAN micro/nanofibers, with several advantages associated with their characteristic large surface area, chemical resistance, thermal stability, low flammability and good mechanical properties, and they have performed well in heavy metal and dye adsorption (Deng & Bai 2003;Saeed et al 2008;Neghlani et al 2011;Deb et al 2019;Deb et al 2020aDeb et al , 2020b.…”

“…It can satisfy the criterion of a material used for adsorption (Saeed et al 2008;Kampalanonwat & Supaphol 2010;Neghlani et al 2011;Huang et al 2013;Deb et al 2020aDeb et al , 2020b. There has been substantial interest in surface modifying PAN micro/nanofibers, with several advantages associated with their characteristic large surface area, chemical resistance, thermal stability, low flammability and good mechanical properties, and they have performed well in heavy metal and dye adsorption (Deng & Bai 2003;Saeed et al 2008;Neghlani et al 2011;Deb et al 2019;Deb et al 2020aDeb et al , 2020b. Modified PAN micro/nanofibers can be regenerated and be reused in other cycles after adsorption (Neghlani et al 2011;Horzum et al 2012).…”

Synthesis and characterization of layered double hydroxide decorated zeolite as the efficient sorbent for removal of toxic metal ions

“…[9][10][11][12][13][14][15] Among them, adsorption technology is an attractive option due to its simple operation, low investment, and potential recovery and reuse of heavy metal ions and oxyanions. [16][17][18] Materials such as zeolites, 19 clays, 20 and layered double hydroxide 21 have been extensively studied for metal ion remediation over these years but these sorbents show low performance for co-removal of heavy metal ions and oxyanions. Therefore, the preparation of sorbents for the co-removal of both heavy metal ions and oxyanions is very useful.…”