Synthetic polyacrylamide as a potential flocculent to remove commercial chromium(III) oxide from aqueous suspension

Abstract

The effects of solution pH and cationic group contents in polyacrylamide (PAM) macromolecules on the polymer adsorption mechanism on chromium(III) oxide surface were studied. The structure of PAM adsorption layer was also characterized to explain the changes in solid suspension stability. The following methods were applied: turbidimetry, spectrophotometry, potentiometric titration and microelectrophoresis. Thanks to them, the stability of the Cr 2 O 3 -polymer systems, polymer-adsorbed amount, surface charge density and zeta potential of solid particles were determined. The experimental results indicate that adsorption of cationic PAM increases with the rising pH. The larger the content of cationic groups in PAM chains is, the higher the adsorption level is observed. The most effective chromium(III) oxide removal is achieved at pH 9 after addition of PAM with the largest content of cationic groups (i.e. 80 %). The neutralization of solid surface negative charge by positively charged polymer chains (assuming more coiled conformation) is responsible for this.

Removal of trivalent chromium from aqueous solution using aluminum oxide hydroxide

“…Several adsorbents (eucalyptus bark, saw dust, sand, clay mineral, charcoal, and various agricultural by products like peanut shell, wheat husk, sugarcane bagasse, biosorption, magnetic beads, carbon nanotubes, Sinorhizobium meliloti 1021 exopolysaccharide, polyacrylic acid, ionic polyamino acid block copolymers, albumins, synthetic polyacrylamide, etc.) have been examined by many scientists for their chromium removal efficiencies in different parts of the world (Gupta et al 2001 ; Garg et al 2004 ; Mohan et al 2006 ; da Fonseca et al 2006 ; Dubey and Gopal 2007 ; Karnitz et al 2007 ; Karale et al 2007 ; Li et al 2008 ; Owlad et al 2009 ; Atieh et al 2010 ; Ramakrishnaiah and Prathima 2012 ; Wiśniewska and Szewczuk-Karpisz 2013 ; Szewczuk-Karpisz et al 2014 ; Mandal et al 2015 ; Ostolska and Wiśniewska 2015 ; Szewczuk-Karpisz and Wiśniewska 2015 ; Wisniewska et al 2016 ). However, there is no report in the literature on the chromium removal using local adsorbents in Ethiopia.…”

Synthesis of nanocomposites from cationic polyacrylamide and modified carbon black: Application as flocculants for oily sludge suspension

“…The oxygen‐containing functional groups of the 1‐CB surface of the nanocomposites can enhance the bridging function . Therefore, with an increase of m 1‐CB : m CPAM , the transmittance was increased . At a mass ratio of m 1‐CB : m CPAM of 2.5:1, the 1‐CB/CPAM composite reached saturation.…”

Removal of Chromium Species by Adsorption: Fundamental Principles, Newly Developed Adsorbents and Future Perspectives

“…To obtain new adsorbents with larger Cr(VI) adsorption capacities, versatile polymers or macromolecules have been further developed, and the Cr removal efficiency has been improved. For example, the cationic group contents in polyacrylamide (PAM) was found to benefit the adsorption of Cr(III) [ 104 ]. A copolymer hydrogel prepared by 2-hydroxyethyl acrylate (HEA) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) exhibited a priority adsorption order of Cr(III) > Fe(III) > Cu(II) > Cd(II) > Pb(II) in a multicomponent solution [ 105 ].…”