The Effect of Dissolved Humic Acids on Aluminosilicate Formation and Associated Carbon Sequestration

Figure 5

²⁹Si SP/MAS NMR spectra of precipitates from solutions with 0.5 mM Si and (a-b) 0.5 mM Al; (c-d) 0.75 mM Al; (e-f) 1.0 mM Al; with and without 6 mg/L DOC as indicated. All spectra were taken under quantitative conditions with a 180 s relaxation delay and 10 kHz spinning rate.