Furan-type Compounds from Carbohydrates via Heterogeneous Catalysis

Biomass derived carbohydrates and related raw materials are the most abundant renewable resources available which have great potential as bio-fuels and chemical building blocks for a diverse range of applications. They can reduce to a large extent our over dependence on fossil-fuel resources. Over the past decade, various acid and/or base catalysts have been used to transform biomass resources into different kinds of furans, providing a feasible way for sustainable energy supply and chemicals. Compared to homogeneous catalytic systems, transformations mediated by heterogeneous catalysts are often associated with distinct advantages such as easy separation, reusability, lower catalyst loading, anti-corrosion effects and simple operation for continuous conversion. In this review, the direct transformation of biomass into furans with the help of heterogeneous catalysts is discussed. The effects of reaction conditions on the intrinsic reactivity and selectivity of each catalytic system are assessed; special emphasis has been paid to comprehend the mechanism for the synthesis of furan-based compounds from biomass resources using heterogeneous catalysts. Keywords: Bio-fuels, biomass resources, heterogeneous catalysis, furans, furfural, heterogeneous, 5-hydroxymethylfurfural, valuable chemicals.