Vanillin made of lignin, Germany found a cost-effective method

Scientists at Johannes Gutenberg University Mainz in Mainz, Germany have developed a new method for preparing vanillin from lignin.

 Lignin is a kind of wood component, which is a large amount of accumulated waste during the pulp production process. Scientists at the University of Gutenberg described the newly developed preparation method in the Journal of Sustainable Chemistry & Engineering of the American Chemical Society: dissolving lignin in caustic soda, and then using a simple nickel electrode with electricity In the electrolytic cell, this mixture is heated to 160 degrees Celsius.

 Lignin is therefore oxidized and decomposed to produce high-quality vanillin. The whole process does not use reactants, so it can be declared as natural vanillin. Professor Siegfried Waldvogel, project developer and coordinator of SusInnoScience research focus at Gutenberg University, said: "After years of intensive research, we have now achieved a real breakthrough."

At present, vanillin is mainly obtained from petroleum. Unlike the above-mentioned new method, its process will produce toxic waste that is difficult to handle. In fact, lignin has been used to prepare vanillin. But Waldvogel pointed out that the past process is very expensive, especially the need to use copper. In addition, past methods can only handle a small portion of lignin waste during pulp production.

 Each year, pulp manufacturing produces more than 100 million tons of lignin, which is later mostly used as fuel. Waldvogel said: "Vanillin prepared by our method accounts for about 4% of the lignin used, so in theory it can easily meet the global demand for vanillin." He firmly believes that the new process is "far superior" The previous vanillin preparation method is not only because it does not generate waste, but also because it is more commercially viable. Currently, he is negotiating with relevant business partners.

The new process mentioned above is part of the EU-funded LIBERATE project. Currently, the process is only applied in the laboratory and will soon be tested on an industrial scale. A partner of Gutenberg University, the SINTEF Institute of Norway, is building a pilot plant for this process. In addition, Waldvogel also plans to further improve the process, not only using pure lignin, but also directly extracting vanillin from black liquor, another by-product of pulp mill wood processing. Pulp black liquor also contains lignin.