title: Integration of decentralized torrefaction with centralized catalytic pyrolysis to produce green aromatics from coffee grounds.
abstract: The aim of this work was to integrate decentralized torrefaction with centralized catalytic pyrolysis to convert coffee grounds into the green aromatic precursors of terephthalic acid, namely benzene, toluene, ethylbenzene, and xylenes (BTEX). An economic analysis of this bioproduct system was conducted to examine BTEX yields, biomass costs and their sensitivities. Model predictions were verified experimentally using pyrolysis GC/MS to quantify BTEX yields for raw and torrefied biomass. The production cost was minimized when the torrefier temperature and residence time were 239°C and 34min, respectively. This optimization study found conditions that justify torrefaction as a pretreatment for making BTEX, provided that starting feedstock costs are below $58 per tonne.
authors.affiliation: Department of Biosystems and Agricultural Engineering, Michigan State University, MI, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Chai
authors.affiliation: Department of Biosystems and Agricultural Engineering, Michigan State University, MI, USA; Department of Chemical Engineering and Materials Science, Michigan State University, MI, USA; Department of Forestry, Michigan State University, MI, USA. Electronic address: saffronc@msu.edu.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Saffron
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Biosystems and Agricultural Engineering, Michigan State University, MI, USA.
authors.forename: Zhongyu
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Biosystems and Agricultural Engineering, Michigan State University, MI, USA.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Munro
authors.affiliation: The Coca-Cola Company, Atlanta, GA, USA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Kriegel
mesh_terms: D001554:Benzene / Q000032:analysis; D001555:Benzene Derivatives / Q000032:analysis; D018533:Biomass; D001709:Biotechnology / Q000191:economics / Q000379:methods*; D002384:Catalysis; D003069:Coffee / Q000737:chemistry*; D003365:Costs and Cost Analysis; D008401:Gas Chromatography-Mass Spectrometry; D008962:Models, Theoretical; D013696:Temperature; D013997:Time Factors; D014050:Toluene / Q000032:analysis; D055549:Volatile Organic Compounds / Q000032:analysis*; D014992:Xylenes / Q000032:analysis
chemical_list: D001555:Benzene Derivatives; D003069:Coffee; D055549:Volatile Organic Compounds; D014992:Xylenes; D014050:Toluene; D001554:Benzene; C004912:ethylbenzene
keywords: Aromatics; Biomass; Catalysis; Pyrolysis; Torrefaction