Water Supply (Aug 2021)
Mesoporous structure regulation of activated carbons and effects on the synergistic efficacy of synchronous adsorption and bio-degradation in biological activated carbon process
Abstract
Mesoporous activated carbon MCGL-4 was tailored for simultaneous enhancement of adsorption and bio-degradation by multistage depth-activation (MDA). Synergistic efficacy of synchronous adsorption and bio-degradation was evaluated in pilot-scale bio-enhanced activated carbon (BEAC) system. Results identified that MCGL-4 obtains synchronously well-developed meso- (0.7605 cm3/g), micro- (0.2655 cm3/g) and macro-porous (0.143 cm3/g) structures. Higher volume during 20.4–208.2 Å (0.6848 cm3/g) ensured higher adsorption capacities for natural organic matters (NOM). The initial immobilized biomass and stabilities on MCGL-4 were also significantly promoted. Rapid small-scale column tests system (RSSCTs) tests showed that adsorption capacities for humic-like organics were 67,725.32 mg·DOC/(kg·carbon) at 39.50 m3·H2O/(kg·carbon). In BEAC system, MCGL-4 achieved higher removal efficiency for fulvic acid, humic acid and aromatic organic matters than commercial carbons. At 39.50 m3·H2O/(kg·carbon), cumulative uptake of organic-pollutants achieved by MCGL-4 was 94,850.51 mg·DOC/(kg·carbon). The proportion occupied by bio-degradation were 31,674.70 mg·DOC/(kg·carbon). It also confirmed that bio-degradation ability was much higher than commercial carbons after mesoporous structures regulation by MDA process. HIGHLIGHTS MCGL-4 was tailored for simultaneous bio-enhancement and adsorption by multistage depth-activation.; MCGL-4 is a promising adsorbent for effective removal of natural organic matters from water.; MCGL-4 was more conductive to simultaneous biodegradation and adsorption of organic-pollutants.; Mesopores (20.4 ∼ 208.2 Å) played important role in adsorption of humic-like organics.;
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