Boosting the aqueous-phase production of lactic acid via dual-site activation of carbohydrates

A series of Zr-based catalysts were prepared using various commercial and cheap organic acids as the coordination agents, and these as-synthesized samples exhibited superior activities to produce lactic acid (LaA) from carbohydrates. Using humic acid (HA) as a typical coordination agent, LaA yield was up to 76% over the resultant Zr-HA, outperforming the most recent reported works. Deeper studies revealed that Zr-HA possessed both acid sites and base sites, and these dual active sites can simultaneously activate xylose, resulting in high yield production of LaA. Besides, Zr-HA also showed excellent reusability and can be reused at least five times.