Glycerol valorization

Valorization of by-products New routes for glycerol and bioethanol upgrading Improved and more efficient catalysts to produce H2 from by-products and waste in liquid phase... 

Shiju NR, Brown DR, Wilson K, Rothenberg G. Glycerol valorization dehydration to acrolein over silica-supported niobia catalysts. Top Catal. 2010 53 1217-23. 

Valorization of the by-product glycerol is absolutely essential for the competitiveness of the process. As the classical markets of glycerol are already saturated by the installed biodiesel capacity, new markets have to be developed, such as feeding component for cattle [3], as an intermediate to prepare a diesel component, or as an intermediate for chemical synthesis. For such markets, different and specific level of purities are required, which are not easy to reach economically. 

Barbirato F, Himmi HE, Conte T, Bories A (1998) PDO production by fermentation an interesting way to valorize glycerin from the ester and ethanol industries. Ind Crops Prod 7 281-289 Biebl H, Marten S (1995) Fermentation of glycerol to 1,3-propanediol use of cosubstrates. Appl Microbiol Biotechnol 44 15-19... 

Papanikolaou S, Aggelis G. (2003). Modelling aspects of the biotechnological valorization of raw glycerol production of citric acid Yarwwia lipolytica and 1,3-propanediol by Clostridium butyricum. J. Chem. Technol. Biotechnol, 78, 542-547. 

This chapter is an overview of architectures adopted for the catalytic/biocatalytic composites used in wide applications like the biomass valorization or fine chemical industry. On this perspective, the chapter updates the reader with the most fresh examples of construction designs and concepts considered for the synthesis of such composites. Their catalytic properties result from the introduction of catalytic functionalities and vary from inorganic metal species e.g., Ru, Ir, Pd, or Rh) to well-organized biochemical structures like enzymes e.g., lipase, peroxidase, (3-galactosidase) or whole cells. Catalytic/biocatalytic procedures for the biomass conversion into platform molecules e.g., glucose, GVL, Me-THF, sorbitol, succinic acid, and glycerol) and their further transformation into value-added products are detailed in order to make understandable the utility of these complex architectures and to associate the composite properties to their performances, versatility, and robustness. 

From the biodiesel production, glycerol was produced at 1.9 Mio mto in 2010/2011 with an annual growth of 15%. In the biorefinery concept, the economic feasibihty of biodiesel production should be based also on the revenues generated by the valorization of coproducts such as glycerol. Moreover, it is important to notice that, in Europe, the availability of other by-products (meals, cakes) leads to a decrease in the dependence of animal feed importation for the agroindustry. 

We showed that oleaginous crops are particularly efficient to produce a large variety of oils and numerous by-products that can be valorized into multiple commodity chemicals. By applying the concept of the whole-plant biorefinery, triglycerides, fatty acids, glycerol, and lignoceUulose are converted into chemicals that can find applications in several markets. 

Aresta M, Dibenedetto A, Nocito F, Ferragina C (2009) Valorization of bio-glycerol new catalytic materials for the synthesis of glycerol carbonate via glycerolysis of urea J Catal 268 106-114... 

Taking into account the above statements, the following section will discuss the catalytic performances of nanofluorides in some applications on biomass valorization such as the cellulose hydrolysis to glucose [145], cellulose valorization to lactic acid [146], and the valorization of glycerol (i.e., the by-product of biodiesel production) to synthesis of diacyl and triacyl glycerine [147], but also the dehydration of xylose and glucose to furan derivatives [148,149]. 

Another example of glycerol valorization with zeolites relies on the hydrogenolysis of glycerol to 1.2-propanediol via bifunctional heterogeneous catalysis [211]. The mechanism involves zeolite-catalyzed dehydration, followed by metal-mediated hydrogenation. 

Valorization of all by-products from the oil industry in a biorefinery concept. The valorization of glycerol and cakes in fermentative processes for the production of biofuels, bioplastics, and value-added chemicals serves as an example (Koutinas et al., 2014). 

Future research incentives on the development of biorefineries should focus on all aspects of the process regarding upstream processing (ie, evaluation of various raiewable raw materials and conversion strategies), bioconversion for SCO production, downstream conversion of SCO into biodiesel or other fuels, and generation of co-products through valorization of cmde glycerol or other side/waste streams. Furthermore, it is essential to evaluate the economic viability and sustainability of industrial-scale, SCO-based biodiesel production. 

Papanikolaou, S., Aggelis, G., 2009. Biotechnological valorization of biodiesel derived glycerol waste through production of single ceU oil and citric acid by Yarrowia lipolytica. Lipid Technology 21, 83—87. 

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