Step 1: Hydrogenation response procedure actions
In a 0.5 L autoclave, add the linalool rectification raffinate where the hefty components have actually been removed and also the driver according to the process needs, switch on the mechanical mixing, and also control the mixing rate at 400-500 r/min. The autoclave was replaced three times with 0.5 MPa nitrogen gas and three times with 0.51 VIPa hydrogen gas respectively. Fill up the autoclave with hydrogen, set the temperature and pressure according to the process requirements, and start the hydrogenation reaction. After the reaction gets to completion factor, the feed liquid is cooled to space temperature, and the feed is released after pressure release. The stimulant was recuperated by centrifugation, and also the make-up of the item was evaluated by gas chromatography.
Step 2: Vacuum distillation of tetrahydrolinalool
The set rectification procedure is adopted, the internal diameter of the glass rectification column is 25 mm, the size of the column is 700 mm, the bottom of the rectification column has a ring-shaped expansion tube, and also the within is full of mm earring-type stainless-steel packing, and also the decompression vacuum system is obtained by a 2ZX.4 rotary vane air pump. Dissipation is controlled by readjusting the voltage of the transformer linked to the sleeve thermostat, the tower top condenser is cooled down with faucet water at room temperature level, and the reflux ratio controller controls the tower leading reflux flow. The stress at the top of the vacuum purification system is 1.3 kPa, the temperature of the tower bottom is managed at 105-115 ° C, and also the back distillation ratio is 10:1. 1. Collect tetrahydrolinalool fractions with a leading temperature of 88-92 ° C/1.3 kPa.
Making use of 5% Pd/C as stimulant, making use of batch hydrogenation response process, 90 ~ 92 ℃, 2.0 MPa, and also response time 4 h, the linalool and also dihydrolinalool in the linalool vacuum cleaner purification raffinate The mass portions were 59.2%, 38.3%, specifically, m (stimulant): (raffinate)=1.2:100, the response yield of synthesizing tetrahydrolinalool from linalool vacuum purification raffinate was 96.3%, and tetrahydrolinalool in the reaction liquid The mass fraction of camphor is 96.5%. Tetrahydrolinalool items with a mass portion higher than 99% as well as a chroma APHA less than 25 can be obtained by rectification under minimized pressure, and also the correction return is 79.2%. The two dual bonds in the linalool particle have different activities throughout the hydrogenation response of 5% Pd/C catalyst system to create tetrahydrolinalool. Methyl-6-octene-3-alcohol, and then more hydrogenation reaction to produce tetrahydrolinalool. In the response process, linalool can form spin-off 2,6-dimethyloctane, P.2-mentene, P. 1( 7 )-mentene, p-mentanol-1, as well as the temperature level of reaction is higher than At 100 ° C, side reactions are considerably accelerated. Tetrahydrolinalool will certainly form oxidized tetrahydrolinalool in contact with air, and also the item must be secured by nitrogen during storage.