Production methods of vanillin
1, Yuka Vanilla bean extract derived.
 Hydrolysis by o-anisidine diazonium into guaiacol in the presence of nitroso-dimethyl aniline and catalyst, and condensation with formaldehyde, or potassium hydroxide catalyst from the reaction with chloroform, and then by extraction, vacuum distillation and crystallization purification derived. Can also be used for wood pulp waste, eugenol, and more guaiacol safrole, etc., made.
To lignin as raw material
You can use the paper mill sulfite pulp waste contained in the preparation of lignin vanillin. General waste containing solids from 10% to 12%, 40% to 50% of calcium lignosulfonate. First waste liquid concentrate containing solid 40 percent to 50 percent, adding 25% of the lignin of NaOH, and heated to 160 ~ 175 ° C (about 1.1 ~ 1.2MPa) through air oxidation of 2h, the conversion rate is generally up to 8% to 11% of the lignin. Oxide with benzene to extract vanillin, and the recovery of benzene by steam distillation method; generate bisulfite bisulfite sodium oxides and impurities separate, and then the sulfuric acid decomposition of vanillin crude product, and finally finished by vacuum distillation and recrystallization.
Guaiacol as raw materials
Chloral method of guaiacol with chloral in the presence of soda ash or potassium carbonate, heated to 27 ° C generated from condensation of 3 - methoxy -4 - hydroxyphenyl trichloromethyl methanol, unreacted more guaiacol was removed by steam distillation. In the presence of caustic soda, using nitrobenzene as oxidant, heated to 150 ° C oxidative cleavage of vanillin; can also be used Cu-CuO-of CoCl2 as a catalyst, air oxidation at 100 ℃, extraction of vanillin reaction with benzene, purified by vacuum distillation and recrystallization was finished.
4, p-hydroxybenzaldehyde France
Hydroxybenzaldehyde as raw material, single bromide, methoxy, prepared by the reaction of vanillin. In a 250mL flask 16g (0.131mo1), 1,4 and 90mL solvent, dissolved drops 6.8mL (0.131mo1) liquid bromine, heated to 40 ~ 45 ℃ reaction 6h. The decompression pumping solvent, the residue add boiling water and filtration, the filtrate cooling and crystallization, filtration, drying white crystals of 3 - bromo - 4 - hydroxy - benzaldehyde, melting point 123 ~ 124 ℃, the yield of 90%.