Porous cage-like microfiber of fly ash magnetic powder (CMS)/polyaniline (PANI) composites with absorption properties

Abstract

In order to recycling adsorbent of wastewater, magnetic adsorbents with recycling properties were prepared by fly ash magnetic powder (CMS)-doped polyaniline microfiber composites (CMS/PANI microfiber). The cheap fly ash magnetic powder is obtained from industrial solid waste fly ash. XRD patterns of CMS/PANI microfiber shows that the peaks at 30o are corresponding to the magnetite in CMS. SEM images shows that CMS/PANI fibrous winding structures forming a porous cage, where microfiber have the diameter of 60 nm and the length of 2-3 um. EDS spectra indicated that the magnetic dots monodispersed on the surface of every root of microfiber. BET surface areas of PANI microfiber and CMS/PANI microfiber are 36.42 m2/g and 25.75 m2/g, respectively. The different wastewater samples has been used including congo red(CR), methyl orange(MO) and halogenated element ions solutions. The maximum adsorption amounts of CR and MO were 324.68 mg/g and 212.3 mg/g, respectively. Interestingly, the CMS/PANI nanofibre material still adsorbs very well to other ionic wastewaters. The magnetic adsorbent achieves a sorption rate of 70% for Ca2+ containing wastewater under certain conditions. The magnetic adsorbent exhibited 48% adsorption of Cl- and over 90% adsorption of F-, Br- and I-. After six cycles of magnetic separation, the adsorption rate was still above 96%. The adsorption curves and equation fits show that the adsorption process is consistent with the langmuir isotherm model and the quasi-secondary kinetic model.

Fabrication of EVOH/PANI Composite Nanofibrous Aerogels for the Removal of Dyes and Heavy Metal Ions

“…In the first 25 min, the adsorption capacity increased quickly with time. Subsequently, the adsorption rate became gentle and reached equilibrium within 50 min, which was faster than most reported adsorbents [ 37 , 38 , 39 ]. The equilibrium adsorption capacity for methyl orange was 9.88 mg/g, 14.40 mg/g, 46.32 mg/g and 73.22 mg/g for initial solution concentrations of 10 mg/L, 20 mg/L, 60 mg/L and 100 mg/L, respectively.…”

Recent Advances in the Removal of Organic Dyes from Aqueous Media with Conducting Polymers, Polyaniline and Polypyrrole, and Their Composites

“…This is based on the observation that any material in contact with the reaction mixture becomes coated with a thin submicrometre film [ 44 ], which is well suited for adsorption purposes. The coating of inorganic substrates is represented by the following: barium titanate [ 45 ]; cobalt ferrite [ 28 ]; cobalt sulfide [ 46 ]; copper(II) oxide [ 47 ]; fly ash [ 48 ]; iron oxyhydroxide [ 49 ]; iron sulfide [ 21 ]; magnetite [ 50 ]; manganese(IV) dioxide [ 34 , 40 ]; manganese ferrite [ 51 ]; magnesium ferrite [ 52 ]; molybdenum trioxide [ 53 ]; montmorillonite [ 54 ]; nickel oxide [ 40 ]; silica gel [ 55 ]; tin dioxide [ 56 ]; titanium dioxide [ 22 , 33 , 57 , 58 ]; zeolite [ 59 ]; zinc oxide [ 60 , 61 , 62 ]; zirconium(IV) dioxide [ 63 ].…”

“…Here, three is a typical number ( Table 1 ). For example, they include some specific parts, such as magnetite or ferrites [ 26 , 42 , 46 , 48 , 50 , 51 , 53 , 82 , 89 , 90 ], which serve the adsorbent separation with a magnetic field.…”