Catalytic Ethanolysis of Fructan-rich and Starchy Expired Food into Biofuel 5-Ethoxymethylfurfural

Catalytic systems were investigated for the ethanolysis of expired food into 5-ethoxymethylfurfural (5-EMF). Fructan-rich expired food (expired probiotics beverage powder, onion powder, garlic powder, and burdock tea), and starchy expired food (expired steamed buns and egg yolk battercake) were tested as starting substrates. Optimization of the reaction conditions included varying the catalyst type, temperature, catalyst loading, and reaction time to maximize 5-EMF yield. Several co-solvents were added to evaluate their impact on the generation of 5-EMF. The selected expired foods produced 5-EMF yields ranging from 0.2 mol% to 68 mol%. The 5-EMF yield from fructan-rich expired food was more noticeably affected by the content of the non-carbohydrate part than that from starchy expired food. The effect of co-solvents on conversion efficiency was closely related to the catalyst type but was not strongly correlated with the feedstock used. This study provides a facile way to produce biofuel chemicals from carbohydrate-rich expired food.