RESULTS OF PROJECT 5, December 2018
Project 5 in BioValue has investigated the use of catalysis for converting sugars into chemicals products. More specifically, tin-containing zeolites have been used for converting C6 sugars, including sucrose, to lactic acid derivatives, and C5 sugars and C2 sugars to novel poly-ester building blocks. Additionally, metal catalysts were used to study the transformation of C2 sugars to glycolic acid and C4 sugars.
One of the most important results in BioValue project 5 is the discovery that alkali ions can be used to alter the reaction pathways occurring during catalysis with the tin-containing zeolites. This has given some degree of control over the catalytic system, and was shown to be an excellent method for optimizing the yield of lactic acid derivatives obtained from C6 sugars. This insight was used for an up-scaled production trial in a pilot unit at Haldor Topsøe, where approximately 100 kg of sugar was converted to lactic acid derivatives using catalysis. Further maturation of the technology has since taken place in a separate project (Cat2BioChem, IFD), focused on exploring the commercial potential for the novel poly-ester building blocks. Some of these have now been produced in kg-scale and tested for various applications. Based on the results from these two projects, the industrial potential for using zeolite catalysis for valorizing sugars has been illustrated. The next step on the path towards commercialization is to build a dedicated pilot plant to further validate the technology and produce larger amounts of samples for application development.
A part of the activities in project 5 in BioValue were also aimed at finding ways to utilize glycol aldehyde (C2 sugar) for the production of other chemicals. Here, two activities were studied: oxidation of glycol aldehyde to glycolic acid by use of supported metal catalysts and oxygen (air) as the oxidant and hydrocyanation of glycol aldehyde to C3 compounds. The first activity on oxidation was unfortunately largely unsuccessful and it was not possible to identify any good catalysts and reaction conditions that gave high yields of glycolic acid in the project. The second project on hydrocyanation was successful, and it was found that glycolaldehyde readily reacts with hydrogen cyanide to make the corresponding cyanohydrin. This can then be transformed into the corresponding amino-alcohol (1,2-dihydroxy-3-aminopropane) or hydrolysed to glyceric acid. A patent application was filed on this hydrocyanation protocol combined with hydrogenation.
In 2017, a new project (OxyCrack, IFD) was started. This project partially builds on some of the developments in BioValue project 5, and especially the activities related to glycol aldehyde (C2) are relevant in this context. The purpose of the ‘OxyCrack’ project is to demonstrate a new technology for the conversion of C6 sugars into C2 in high yields. Here, further conversion of C2 to other chemicals and the learnings from BioValue (including what not to do), will be used for future development activities in this area.
All in all, it is clear that BioValue has served as an incubator for many of the activities that are now ongoing in the area of catalytic conversion of sugars, which are now an important part of the future technology pipeline at Haldor Topsøe.