Concept of rice husk biorefining for levulinic acid production integrating three steps: Multi-response optimization, new perceptions and limitations. (February 2018)

• Record Type: Journal Article
• Authors: Fleig, Olivia Paniz; Lopes, Emília Savioli; Rivera, Elmer Ccopa; Maciel Filho, Rubens; Tovar, Laura Plazas
• Is Part Of: Process biochemistry. Volume 65(2018)
• Page Start: 146
• Page End: 156
• Publication Date: 2018-02
• Subjects: Rice husk -- Levulinic acid -- Humins -- Desirability function -- Lignocellulosic biorefinery -- Biorefinery optimization; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2017.11.015
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: Integrated three-step conversion in a biorefining of rice husk to levulinic acid. New insight into selective conversion of rice husk to value bio-based products. Derringer's desirability function is useful for multi-response optimization. New perceptions provide levulinic acid in a highly selectivity (62.2%). Lower released humins were recovered as solid byproducts. Abstract: Valuable intermediates for solvents, biofuels and biopolymer precursors are produced from levulinic acid (LA). In this study, rice husk (RH) was fractionated using a three-step biorefining approach for LA production: (1) acid pretreatment, (2) alkaline pretreatment and (3) catalytic depolymerization of cellulose. In third step, the H2 SO4 -acid concentration ( A d ), reaction temperature ( T d ) and reaction time ( t d ) on the LA concentration ( CLA ), selectivity ( SLA ) and yield percentage based on the theoretical value ( Yt, LA ), were investigated. Optimal values for CLA of 27.2 g/L, SLA of 62.2% and Yt, LA of 60.6 mol% were obtained at A d of 5.0% w/v, T d of 175 °C and t d of 75 min. A scenario based on 100 kg of dry RH produced 11.8 kg of LA with a yield of 42.9 mol% based on the theoretical values of the cellulose in the RH, as well as 12.5 kg of xylose, 12 kg of lignin and 2.9 kg of formic acid. Furthermore, the potential route to LA production with the requirement to remove the ash and with a low production of carbonaceous species (∼2.5 kg) was highlighted in this study. These results offer new insight into selective conversion of RH to bio-based products.