Catalytic oxidation of lignin in the medium of nitrobenzene with vanillin obtaining

Lignin, due to its structure, is a very valuable supplier of aromatic aldehydes which find wide application in food, chemical and pharmaceutical industries. One of these substances is vanillin, which is widely used in pharmaceutical chemistry. Derivatives of vanillin have antiseptic and antibacterial properties. Drugs, derived from vanillin, are used to stimulate digestion, to treat cardiovascular diseases. Nitrobenzene is the most selective oxidant of lignin and therefore gives the highest possible yield of aromatic aldehydes and is more preferable in comparison with oxygen, despite its toxicity. The most common catalyst for nitrobenzene oxidation of lignin is copper, however, such catalysts is quite difficult to regenerate and recover. This article describes the oxidation of lignin with nitrobenzene in an alkaline medium in the presence of a catalyst 3% Ru/MN270. MN270 is a hypercrosslinked polystyrene in the pores of which can be obtained an active and stable metal particles by the method of impregnation.