Synthesis And Application On Thymol

Study on the synthesis of thymol and menthol were introduced. Recent advances in synthesis of thymol, focusing on the application of solid catalyst were reviewed mainly. Zinc aluminate was prepared and detected by XRD, IR, BET and TPD. Self-prepared zinc aluminate has the spinel structure. The Zinc aluminate has the specific surface area of 95.21m2/g, the Pore volume of 0.174cm3/g, the pore diameter of 6.3 nm. There are a little-OH in tne surface of zinc aluminate according to IR, the r-alumina has the specific surface area of 79.5m?/g, the Pore volume of 0.2cm3/g, the pore diameter of 8.4cm3/g. It can prove that there has-OH in tne surface of the r-alumina. The results of TPD proves that there has acidic sites in the surface of zinc aluminate spinel andγ-Al2O3. The absorbance of NH3 of zinc aluminate spinel is 322 umol/g, ofγ-Al2O3 is 307 umol/g.thymol was synthesized from m-cresol and isopropyl alcohol via a gas phase Friedel-Crafts reaction, which employing the self-prepared zinc aluminate orγ-Al2O3 as the catalysts. The temperature and time of reaction, proportion of material and flow speed of materials was discussed. the optimal reaction's condition is 0.2mlL/min of flow speed of materials,1:3 of proportion of material,2h of time of reaction,573K of temperature of reaction with the zinc aluminate as catalyst. The selectivity reaches up to 86.9% and the m-cresol conversion reaches up to 51.2% at the optimal reaction's condition. And the stability is good for a long time in use. M-cresol conversion rate will be maintained at 51%, and The selectivity of product will be maintained at 85-86%.Life of the catalyst reaches to 260 hours. The optimal reaction's condition is 0.2 mL/min of flow speed of materials,1:5 of proportion of material,2 hours of time of reaction,603K of temperature of reaction with theγ-alumina as catalyst. The selectivity reaches up to 73.6% and the m-cresol conversion reaches up to 68.5% at the optimal reaction's condition. Life of the catalyst reaches to 250 hours. And the stability is also good for a long time in use. M-cresol conversion rate will be maintained at 64-74%, and The selectivity of product will be maintained at 60.5-68.6%.The menthol was synthesized from thymol via hydrogenation. This article compares the different elements, different from the activity of Raney nickel and Ni-Cr2O3 on the reaction, The results showed that 1% of the titanium-containing Raney(T1) nickel catalysts is the best catalyst for the reation. The most optimum conditions is 20-30atm of pressure,200-220℃temperature.. The menthol was synthesized with Pd/C as catalyst, The results showed that the products are menthone and iso-menthone.