Study of the Purification from Cashew Nut Shell Oil and Antioxidation of Cardanol
|Keywords||Cardanol Oxidation resistance Purification process Index|
This article give a certain amount of research and analysis on the the cardanol extraction process and indicators; due to the cardanol the instability, choose different antioxidants made some research on the the cardanol oxidation resistance and storage methods. With infrared spectroscopy and liquid chromatography - mass spectrometry to determine the types of cardanol, cardanol four kinds: Cardanol Ⅰ, Cardanol Ⅱ, Cardanol Ⅲ, Cardanol Ⅳ. The molecular weight of the order of 297,299,301,303. High performance liquid chromatography (HPLC) method was measured the four cardanol concentration ratio: Cardanol: Ⅰ Cardanol Ⅱ: Cardanol Ⅲ: Cardanol Ⅳ = 2.00:36.75:20.44:40.81. Cardanol, were analyzed Results: The proportion of :0.9250-0 .9400 g /, cm ~~ 3 (20 ° C); chroma :3-6; :42-48 viscosity mPa.s (30 ° C); iodine value: ≥ 200 g / 100g; Moisture: <1%; Ash <0.1%; acid value :6.0-7 .0 mg / g (with KOH). By vacuum distillation to extract cardanol determine the cardanol the extraction process, get the process operating parameters: the degree of vacuum: 500Pa: tower kettle highest temperature: 220 ℃; operating time: 1.5h; cardanol purity of this operation process conditions more than 95%, and the yield can reach 93%. Cardanol enlarged experiment, adjustments of the purification process of the cardanol. Enlarge the optimum process parameters: vacuum degree: 2000Pa; tower kettle highest temperature: 240 ° C: Operating time: 2.0h; purity of 95% up to 91% yield. Cardanol Iodine result not only of the unsaturated double bonds in the side connected to a great relationship with the phenolic hydroxyl group on the benzene ring, the smaller the degree of oxidation of phenolic hydroxyl, an iodine value bigger. Therefore, changes in the results of the cardanol Iodine can characterize its stability, placed in the air exposure time (50 days), the smaller the change of the Iodine results, showed cardanol better stability. Adding a certain percentage (0.01%) in the homemade cardanol different anti-oxidant, for a certain time in the air exposure (30 days), by the iodine number and the chromaticity measurement, its antioxidant. Single component antioxidant, antioxidant effect size order phenothiazine> BHT: DBHQ ≈ TBHQ in which the DBHQ (iodine value 195g/100g, chroma 5), and TBHQ (the iodine value 196.8g/100g, chroma 4) the best antioxidant effect. The multicomponent antioxidants affect the size of the order: DBHQ TBHQ in> TBHQ in phenothiazine> BHT DBHQ ≈ BHT TBHQ in> phenothiazine BHT antioxidant properties of cardanol. The DBHQ TBHQ (Iodine value 199.87g/100g the chrominance 5) antioxidant effect. The antioxidant is added the cardanol storage good measures.