Metal-contaminated biochars as cheap and more sustainable catalysts for furfural conversion to value-added compounds

Furfural is an important biobased building block molecule to produce several value-added compounds for the fine chemical industry, biofuels, and biopolymers through a catalytic pathway. Developing cheaper and more sustainable catalysts to promote furfural conversion reactions is imperative to meet the Green Chemistry prin-ciples and obtain biobased products through greener routes. In this sense, sewage sludge-derived biochars emerge as promising materials that catalyze furfural conversion reactions since they possess acid and basic surface sites due to their high metal content and organic structure. This paper reports the employment of two sewage sludge-derived biochars as catalysts for furfural conversion, an encouraging application for these solids with severe environmental concerns. These materials were fully characterized regarding their composition, structure, textural, morphological, acidic, and surface properties, displaying the presence of acid (Lewis and Bronsted) and basic sites. These biochars presented good activity for converting furfural (26.5-68.8%) and high selectivity to furfuryl alcohol (43.6-90.6%). In addition, other value-added products were observed, such as furfural-derived ethers, ester, and ketone.

Automated summary

This study reports the application of sewage sludge-derived biochars as catalysts for furfural conversion, showing good activity and selectivity, as well as the generation of other valuable products.