The diminishing fossil fuel reserves and greenhouse gas emissions have made it imperative for the chemical industry to produce bio-based alternatives as a replacement of petroleum-based platform chemicals. This chapter primarily focuses on 2,5-furandicarboxylic acid (FDCA), a bio-based precursor that can be further utilized in the synthesis of a various chemicals and polymers. The synthesis of FDCA involves chemical, electrocatalytic, and biological methods, wherein the chemical methods have proven most favourable in terms of productivity, purity, and reaction rate. The chemical pathway for FDCA synthesis involves carbohydrate dehydration into 5-hydroxymethylfurfural (HMF), which is oxidized into FDCA. To achieve maximum FDCA production, it is important to select an efficient catalytic system that can give high HMF yields and can also be scaled up in the future. Therefore, this chapter enlists different catalytic systems for HMF synthesis including homogeneous catalytic systems, biphasic catalytic systems, ionic liquids, and heterogenous catalytic systems. The substrate plays a major role in controlling the scalability, productivity, and economics to produce HMF and FDCA. Agricultural residues and food wastes represent significant, yet underutilized, sources of biomass that can be leveraged to produce valuable chemicals. Agricultural residues include the non-edible parts of crops, such as straw, husks, and stems, which are typically left in the field after harvesting. Food wastes encompass a wide range of materials discarded during the processing, distribution, and consumption of food, including peels, pulp, and spoiled or uneaten food. Both categories of biomass are rich in carbohydrates, such as cellulose, hemicellulose, and starch, which can be converted into HMF and FDCA as described in this chapter. These chemicals are crucial to produce bio-based plastics, resins, and other sustainable materials, offering a promising route to reduce reliance on fossil fuels and mitigate environmental impacts.