Towards a Sustainable Production of Furfuryl-Alcohol: Conversion of Residual Biomass By Pyrolysis

HOCH, P.M.; VOLPE, M.A.

Boston, MA

Congreso; AICHE Annual Meeting 2021; 2021

AICHE

Due to the natural resistance of plant cell wallsto microbial and enzymatic rupture, biochemical transformations oflignocellulosic materials are particularly difficult to carry out (Himmel etal., 2007). Pyrolysis arose as a process of choice for this kind ofmaterials because it can rapidly transform biomass producing liquid, gas andsolid products (Lim et al., 2016). The liquid, known asbio-oil, is universally regarded as a source for fuels and chemicals(Bridgewater, 2012).As a source of lignocellulosic material, sunflowerseed hulls are abundant residues of the edible oil industry, especially in thesouth region of Buenos Aires, Argentina, where approximately 22 thousand tonsare accumulated per year. This material could be considered a very promisingsource of biomass for carrying out pyrolysis processes for either fuel or Value-addedProducts production, due to the amount produced each year and the fact that theraw cost material is null, because it is otherwise a waste mainly used forenergy production by burning. The environmental issues derived from the hullsburning include fumes and unpleasant odors, and it looks more sensible to finda profitable use.There are several possible products to be obtainedafter the hulls are pyrolyzed, depending on the conditions of the pretreatmentand the process itself. In particular, after the fast pyrolysis is performed, amixture containing a bio char and a bio liquid is obtained. The bio char can beused for example as a replacement for coal, while the bio liquid must undertakeseveral purification steps in order to obtain the desired products.Continuing our interest in adding value tosunflower seed hulls, we analyze the production of furfuryl alcohol after thepyrolysis and bioliquid separation is performed. As it was already mentioned, afirst step a bio-oil rich in furfural is obtained from the pyrolysis of thehulls. Second, this bio-oil is sent to a catalytic treatment for convertingfurfural into furfuryl alcohol, using Pd based catalysts in a Batch reactorunder mild conditions (at 110°C and 0.4 MPa of H2). The Pd basedcatalysts, Pd/BCs, used for the laboratory scale process, are prepared bysupporting palladium on bio-chars which are also a co-product of pyrolysis ofthe hulls. The conversion of furfural and the selectivity to furfuryl alcoholare analyzed for the different catalysts, in the context of the evaluation ofthe possibility of producing VAP from the hulls (Casoni et al, 2018)In this work, besides the experimental work done inorder to find the best laboratory conditions for the production of value-addedproducts derived from the pyrolysis of sunflower seed hulls, a mathematicalmodel of a large scale process is proposed and embedded into a superstructureconsidering different alternatives for pretreatment, pyrolysis conditions,post-pyrolysis separation of the bioliquid, catalyst selection including butnot limited to preparation on bio chars, and post catalytic hydrogenation stepseparation of products is set up, with models based on first principles at aconceptual level, including mass and energy balances. A Generalized Disjunctiveprogramming problem is now posed in order to find a setup using as objectivefunction the Net Present Value. This constitutes a deeper study of the processpresented in Casoni et al (2018), where an initial proposal waspresented for an industrial scale facility.Besides the furfuryl alcohol, several value-addedproducts can be obtained from agro-industrial residues by applying themethodology introduced in this study, thus new green processes for replacingthe traditional ones can be developed.ReferencesBridgewater A.V., 2012. Review of fast pyrolysis ofbiomass and product upgrading. Biomass Biosenergy. 38, 68-94.Casoni, A.I., Volpe M.A., Hoch P.M. Gutierrez V.S.,2018. Catalytic conversion of furfural from pyrolysis of sunflower seed hullsfor producing bio-based furfuryl alcohol, Journal of Cleaner Production 178,237-246Himmel M.E., Ding S.Y., Johnson D.K., Adney W.S.,Nimlos M.R., Brady J.W., Foust T.D., 2007. Biomass recalcitrance: engineeringplants and enzymes for biofuels production, Science 315, 804-807.Lim, C.H., Mohammed, I.Y., Abakr, Y. A., Kazi,F.K., Yusup, S., Lam, H. L., 2016. Novel input-output prediction approach forbiomass pyrolysis. J. Clean.Prod. 136, 51-61