Efficient removal of humic acid in aqueous solution using polyaniline adsorbent

Abstract

2012) Efficient removal of humic acid in aqueous solution using polyaniline adsorbent, Desalination and Water Treatment, 40:1-3, 92-99, A B S T R AC TPolyaniline adsorbent prepared by chemical oxidation was developed to remove the humic acid (HA) in aqueous solution. The adsorbents showed the high adsorption capacity for aqueous HA with the maximum adsorption amount 126.58 mg g −1 , and the adsorption isotherm obeyed the Langmuir model. The adsorption kinetics followed an initial diffusion-controlled and then an attachment-controlled adsorption process. The HA adsorption was not much impacted in the presence of Na + , K + , while Ca 2+ ion in aqueous solution can evidently enhance the HA adsorption. The HA adsorption on polyaniline decreased with increasing solution pH owing to the electrostatic interaction between imine and amine of polyaniline and disassociated HA. The HA molecules adsorbed on the polyaniline can be effectively desorbed in 0.1 M NaOH solution, and regenerated adsorbent can be repeatedly used in the subsequently adsorption-regeneration cycles.

Kinetic Study of the Adsorption of Natural Organic Matter From Aqueous Solution by Surfactant Modified Zeolite

“…In addition, it is noticeable that NOM molecular size may increase from a spherical structure form at low pH to a linear structure form at high pH, which also indicates the reduction of NOM adsorption at increased pH values (15,17). Many studies have reported the similar results for other adsorbents (32)(33)(34). The aim of this study was to use the acquired experimental data for application in the water treatment where the pH of the water is in the range of 5 -7.…”

Removal of Disinfection By-Products Precursor (Humic Acid) by Graphene-Silica Composites

“…The adsorption removal effectiveness of NOM onto RGO-SiO2 is observed to be slightly reduced after three cycles, and no obvious decrease after the next cycle, which indicates that the regenerated RGO-SiO2 retains its outstanding NOM adsorption removal effectiveness in surface water, and the adsorbent can be reused [10]. The removal capacity of RGO-SiO 2 on haloacetic acid (HAAsFP) is higher than trihalomethane (THMsFP), which is owing to the precursor of HAAs being mainly hydrophobic organic compounds [22]. The adsorption capacity of RGO-SiO 2 on hydrophobic organic compounds in water is stronger.…”

“…The removal capacity of RGO-SiO2 on haloacetic acid (HAAsFP) is higher than trihalomethane (THMsFP), which is owing to the precursor of HAAs being mainly hydrophobic organic compounds [22]. The adsorption capacity of RGO-SiO2 on hydrophobic organic compounds in water is stronger.…”