负载型贵金属铂催化剂催化氢化大豆油的性能研究  

The Catalytic Hydrogenation of Soybean Oil over the Noble Metal Platinum Supported Catalyst

作　　者：杨希[1] 陈奕[1] 聂少平[1] 谢明勇[1] 

机构地区：[1]南昌大学食品科学与技术国家重点实验室,南昌330047

出　　处：《中国粮油学报》2014年第5期58-64,共7页Journal of the Chinese Cereals and Oils Association

基　　金：973计划(2012CB720805)

摘　　要：油脂氢化是利用还原性镍等金属作为催化剂,使氢加成到三酰甘油双键上的过程。但在氢化过程中会不同程度地产生异构化产物——反式脂肪酸(TFAs)。因此学术界一直研究如何降低氢化过程中TFAs含量的方法,尤其是对催化氢化中各类催化剂的制备与性能的探究。通过制备二氧化锆(ZrO2)负载贵金属铂的催化剂,在工业条件下氢化大豆油并与雷尼镍催化剂对比其活性、反应选择性以及产生TFAs的含量。采用浸渍-还原法制备负载贵金属铂的催化剂,利用常用的表征手段如XRD、TEM、BET、ICP等对催化剂进行物理化学表征;同时在工业氢化条件下对大豆油进行催化氢化,对比各催化剂的活性、选择性以及TFAs的含量,且进一步对比氢化后油脂的品质指标如酸价、熔点。结果表明,ZrO2负载贵金属铂催化剂的活性极明显高于镍催化剂,且在碘值约为70时产生的反式酸含量为25.48 g/100 g大豆油,低于镍催化剂产生的反式酸(31.42g/100 g大豆油)。负载铂催化剂氢化后油脂的酸价稳定并且小于1.0 mgKOH/g;油脂的滑动熔点值显著上升,最终高达45.08℃。在工业氢化条件下,ZrO2负载的铂催化剂为典型的介孔材料,金属粒径小,金属分散性很好,具有高活性,低TFAs含量等优点。The industrial hydrogenation of edible oil is a process of introducing the double bonds of the triglyceride in the presence of Raney Ni catalyst. Since the hydrogenati hydrogen molecule to the on process would result in the production of saturated and trans fatty acids （TFAs）, it＇s urgent to develop new technologies to minimize the con- centration of trans -fatty acids in hydrogenated products. Especially the researches on the preparation and perform- ance of catalysts adopted in the hydrogenation will be focused. In order to increase the activity and selectivity of the catalysts adopted for the soybean oil hydrogenation, the nobel platinum supported on zirconium dioxide catalyst has been prepared and compared with the Raney Ni on industrial hydrogenation conditions. The platinum supported cata- lyst was synthetized by wet impregnation method. The catalyst was characterized through XRD, TEM, BET and ICP AES. Then the hydrogenation with each catalyst has been carried out on the industrial hydrogenation condition. The activity, selectivity and effects on the formation of trans fatty acids were investigated in hydrogenation reaction and compared with Raney Ni catalyst. Moreover, the physical and chemical properties of hydrogenated oil such as acid value and melting points were also analysed. The results showed that the activity of the platinum based on zirco- nium dioxide catalyst was found to be much higher than the nickel catalyst. The formation of TFAs in the hydrogenated soybean oil was 25.48 g/100 g oil with an iodine value of 70, which was lower than the commercial nickel catalyst （31.42 g/100 g oil）. The acid value of hydrogenated oil was stable and less than 1.0 mg KOH/g. The sliding melting points of the platinum supported on zirconium dioxide increased significantly, ultimately reach to 45.08 ℃. The platinum supported on zirconium dioxide catalyst, a typical mesoporous material with small partical size in nanoscale and finely dispersion of metal platinum was indicated to have a higher activity

关 键 词：油脂氢化 反式脂肪酸 二氧化锆 贵金属铂 熔点 酸价 

分 类 号：TQ645[化学工程—精细化工]