Catalytic valorisation of various paper wastes into levulinic acid, hydroxymethylfurfural, and furfural: Influence of feedstock properties and ferric chloride

Lignocellulosic paper waste constitutes a major waste stream globally, which should be valorised for chemical production. However, paper properties (e.g., feedstock composition, cellulosic crystallinity, and thermal stability/degradability) vary with raw materials and pulping processes. This study investigated levulinic acid (LA), hydroxymethylfurfural (HMF), and furfural production by H2SO4 and FeCl3 catalysed conversion of nine types of paper wastes in a green solvent system (1:1 gamma-valerolactone/water). At 160-180 degrees C for 1-20 min, similar to 23-27 wt% LA yield was achieved from sanitary papers, tracing/parchment paper, and paper food box mainly containing crystalline cellulose, while a lower LA yield (similar to 10-20 wt%) was obtained from other paper wastes with high contents of ash and lignin. A higher selectivity towards HMF (similar to 12 mol%) was achieved in the presence of FeCl3. A furfural yield of similar to 4-7.5 wt% was also obtained from the hemicellulose content. This study elucidates crucial factors and desirable characteristics of paper waste for catalytic valorisation.

Automated summary

This study investigated the catalytic valorization of different types of paper wastes for chemical production. The properties and composition of paper significantly affect the yield and selectivity of the products, highlighting the importance of considering these factors in the valorization of paper waste.