Chemical Synthesis of Adipic Acid from Glucose and Derivatives: Challenges for Nanocatalyst Design

Adipic acid is an essential building block for the nylon industry, but its production continues to rely on fossil-derived benzene and generates a substantial amount of N2O every year. Recognizing the environmental impact of conventional adipic acid production and motivated by societal interests toward a sustainable future, the production of adipic acid should switch toward a renewable feedstock and proceed with a nitric acid-free protocol. In light of this transition, glucose emerges as a suitable feedstock to replace benzene for bioadipic acid production. It can be chemically converted into bioadipic acid via two different routes, forming either glucaric acid or 2,5-furandicarboxylic acid as the respective key intermediates. However, these transformations are challenged by various issues, such as retro-aldol condensation, which fragments glucose into smaller organic byproducts, and catalyst instability, which compromises the reaction rates. This perspective addresses the potentials and challenges in nanocatalyst design and discusses how catalyst morphology tailoring and metal-support interaction tuning can be revised systematically to maximize the yield of bioadipic acid. The influence of catalyst structures on selective activation of C-H (oxidation) and C-O bond (hydrogenolysis) of the intermediates is critically discussed. The electronic features of bimetallic and metal-acid/base hybridized catalysts on C-H and C-O bond activation have been correlated in this work. The goal of this perspective aims to provide insights on novel nanocatalysts designed to improve bioadipic acid production from sustainable feedstocks.