Effects of Polymer Molecular Weight on Adsorption and Flocculation in Aqueous Kaolinite Suspensions Dosed with Nonionic Polyacrylamides
<p>Experimental results of adsorption tests: (<b>a</b>) adsorption isotherm curves of 1.5 K, 10 K, 0.6–1 M, 5–6 M, and 18 M polyacrylamides (PAMs), representing the PAM adsorption capacity (<span class="html-italic">i.e.</span>, the solid-phase equilibrium PAM concentration; <span class="html-italic">q<sub>e</sub></span>) <span class="html-italic">versus</span> the solution-phase equilibrium PAM concentration (Ce) and (<b>b</b>) maximum adsorption capacity <span class="html-italic">versus</span> PAM molecular weight.</p> "> Figure 2
<p>Experimental results of steady-shear viscosity measurements: (<b>a</b>) steady-shear viscosity <span class="html-italic">versus</span> shear rate at different polyacrylamide (PAM) concentrations for 18 M PAM and (<b>b</b>) zero-shear specific viscosity <span class="html-italic">versus</span> PAM concentration for 1.5 K, 10 K, 0.6–1 M, 5–6 M, and 18 M PAMs.</p> "> Figure 3
<p>Schematic diagram of equilibrium and nonequilibrium flocculation mechanisms in kaolinite suspensions dosed with polyacrylamides.</p> "> Figure 4
<p>Experimental results of flocculation tests performed using 0.6–1 M and 5–6 M polyacrylamides (PAMs) at different shear rates and contact times. (<b>a</b>,<b>b</b>) represent PAM adsorption capacity <span class="html-italic">versus</span> PAM concentration for 0.6–1 M and 5–6 M, respectively. The x-axis represents the total dosed PAM concentrations in the left-hand panels, and solution-phase PAM concentrations in the right-hand panels.</p> "> Figure 5
<p>Experimental results of flocculation tests performed using 0.6–1 M and 5–6 M polyacrylamides (PAMs) at different shear rates and contact times. (<b>a</b>,<b>b</b>) represent the residual turbidity (final turbidity/initial turbidity) <span class="html-italic">versus</span> PAM concentrations for 0.6–1 M and 5–6 M, respectively. The x-axis represents the total dosed PAM concentrations in the left-hand panels, the solution-phase PAM concentrations in the middle panels, and the solution-phase PAM concentrations in the right-hand panels.</p> ">
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Adsorption Tests
2.3. Viscosity Measurements
2.4. Flocculation Tests
3. Results and Discussion
3.1. PAM Adsorption on Kaolinite
MW (g/mol) | q,max (mgPAM/gKaolinite) | Ks (mgPAM/L) | R2 |
---|---|---|---|
1.5 K † | 0.7753 | 12.542 | 0.9280 |
10 K | 0.9951 | 3.8749 | 0.9078 |
0.6~1 M ‡ | 17.941 | 1.0811 | 0.9851 |
5~6 M | 26.796 | 3.3032 | 0.9730 |
18 M | 0.8718 | 1.2365 | 0.9128 |
3.2. Entanglements in High-MW Polymeric Solutions
3.3. PAM-Mediated Particle Flocculation
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Lee, B.J.; Schlautman, M.A. Effects of Polymer Molecular Weight on Adsorption and Flocculation in Aqueous Kaolinite Suspensions Dosed with Nonionic Polyacrylamides. Water 2015, 7, 5896-5909. https://doi.org/10.3390/w7115896
Lee BJ, Schlautman MA. Effects of Polymer Molecular Weight on Adsorption and Flocculation in Aqueous Kaolinite Suspensions Dosed with Nonionic Polyacrylamides. Water. 2015; 7(11):5896-5909. https://doi.org/10.3390/w7115896
Chicago/Turabian StyleLee, Byung Joon, and Mark A. Schlautman. 2015. "Effects of Polymer Molecular Weight on Adsorption and Flocculation in Aqueous Kaolinite Suspensions Dosed with Nonionic Polyacrylamides" Water 7, no. 11: 5896-5909. https://doi.org/10.3390/w7115896