Combined conversion of lignocellulosic biomass into high-value products with ultrasonic cavitation and photocatalytic produced reactive oxygen species – A review

• Published in: Bioresource technology 2023-01, Vol.368, p.128333-128333, Article 128333
• Main Authors: Djellabi, Ridha, Aboagye, Dominic, Galloni, Melissa Greta, Vilas Andhalkar, Vaibhav, Nouacer, Sana, Nabgan, Walid, Rtimi, Sami, Constantí, Magda, Medina Cabello, Francisco, Contreras, Sandra
• Format: Article
• Language: English
• Subjects: Biomass valorization; Circular bioeconomy; Photocatalysis; Selective scission of C–C/C–O; Ultrasonic vibration
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.128333

[Display omitted] •Mechanisms of photoproduced ROSs to cleave crosslinked CC/CO in biomass.•Photocatalytic materials design and operating factors for biomass conversion.•Impact of ultrasonic vibration on the mass transfer and biomass valorization.•Synergistic effects of sonophotocatalysis to boost the yield of high value products.•Future directions for the optimization of sonophotocatalytic biomass conversion. The production of high-value products from lignocellulosic biomass is carried out through the selective scission of crosslinked CC/CO bonds. Nowadays, several techniques are applied to optimize biomass conversion into desired products with high yields. Photocatalytic technology has been proven to be a valuable tool for valorizing biomass at mild conditions. The photoproduced reactive oxygen species (ROSs) can initiate the scission of crosslinked bonds and form radical intermediates. However, the low mass transfer of the photocatalytic process could limit the production of a high yield of products. The incorporation of ultrasonic cavitation in the photocatalytic system provides an exceptional condition to boost the fragmentation and transformation of biomass into the desired products within a lesser reaction time. This review critically discusses the main factors governing the application of photocatalysis for biomass valorization and tricks to boost the selectivity for enhancing the yield of desired products. Synergistic effects obtained through the combination of sonolysis and photocatalysis were discussed in depth. Under ultrasonic vibration, hot spots could be produced on the surface of the photocatalysts, improving the mass transfer through the jet phenomenon. In addition, shock waves can assist the dissolution and mixing of biomass particles.