Comparative techno-economics of 1,3-butadiene production from sugarcane feedstocks via ethanol or 2,3-butanediol as intermediates

• Published in: Industrial crops and products 2024-02, Vol.208, p.117872, Article 117872
• Main Authors: Gouws, Mirelle René, Dogbe, Eunice Sefakor, Bosman, Catharine Elizabeth, Görgens, Johann Ferdinand
• Format: Article
• Language: English
• Subjects: Bio-based 1,3-butadiene; Bio-based 2,3-butanediol; Bioethanol; Biorefinery; Feedstocks; Techno-economic analysis
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2023.117872

The global sugar industry has stagnated due to oversupply of the markets with conventional sugar products. Shifting from sugar-only production to co-production of other valuable products, through the integration of biorefineries into existing sugar mills, may open new revenue streams and investment opportunities. The economic feasibilities of various biorefinery scenarios for the production of 1,3-butadiene, by annexation to an existing sugar mill, were investigated. Pathways using either 2,3-butanediol or ethanol as intermediate product were compared, using A-molasses (first-generation), and sugarcane bagasse and brown leaves (second-generation) as feedstocks. The processes were simulated from literature data using Aspen Plus® software for subsequent techno-economic and sensitivity analyses. Producing 1,3-butadiene via the 2,3-butanediol pathway proved to have more attractive economics, with minimum selling prices of 4.08 $/kg and 4.55 $/kg for first-generation-only and integrated/combined first- and second-generation feedstocks, respectively, compared to the ethanol pathway at 5.71 $/kg and 5.72 $/kg. This was mainly attributed to low catalytic performance and higher capital costs associated with the ethanol-to-butadiene catalytic conversion. The investigated scenarios were unprofitable compared to a market price of 1.05 $/kg for fossil-derived 1,3-butadiene, requiring substantial price premiums for bio-based 1,3-butadiene. Instead, the sole production of bio-based 2,3-butanediol as final biorefinery product was deemed to be more viable for investment. •Four 1,3-butadiene sugarcane mill annexed biorefinery scenarios were developed.•1,3-butadiene production using ethanol or 2,3-butanediol intermediates was compared.•2,3-butanediol pathway more cost-effective than ethanol pathway.•Catalytic upgrading of intermediates critical to economic performance.