Pt/HPW/ZrO2催化甘油脱氧制取1,3-丙二醇

以磷钨杂多酸为钨前驱体用浸渍法制备系列具有不同Pt含量和不同HPW/ZrO2焙烧温度的Pt/HPW/ZrO2催化剂。通过BET比表面积、红外光谱和X线衍射方法表征催化剂的结构,在连续流动固定床反应器中考察其对甘油水溶液催化脱氧制取1,3-丙二醇(1,3-PDO)反应催化性能的影响。结果表明:ZrO2负载磷钨杂多酸经500℃以上温度处理,磷钨杂多酸分解为相应的氧化物,单斜相WO3和磷氧化物分散在ZrO2表面。Pt/HPW/ZrO2催化剂对甘油脱氧反应具有较高的催化活性。铂负载量、HPW/ZrO2焙烧温度、反应温度、压力及甘油浓度等因素的变化,对甘油转化率和1,3-PDO收率的影响较大。在4 MPa、130℃、液体体积空速(LHSV)为0.25 h-1的反应条件下,2.0%Pt/HPWZ10(700)催化剂上60%甘油水溶液催化脱氧反应可得到53.4%甘油转化率和44.5%的1,3-PDO选择性,产物中1,3-PDO与1,2-丙二醇(1,2-PDO)摩尔比值达到14.3。100 h稳定性实验表明催化剂性能稳定。

Catalytic performance of Pt/HPW/ZrO2 for glycerol deoxygenation into 1,3-propandiol

A series of Pt/HPW/ZrO2 catalysts with different Pt loadings and calcination temperatures were prepared by the impregnation method with tungstophosphoric acid as the tungsten precursor.Their BET specific surface areas and crystalline phase structures were determined using N2 adsorption,infrared spectroscopy and X-ray diffraction.Deoxygenation of glycerol in aqueous medium into 1,3-propandiol was performed on these catalysts in a fixed-bed continuous-flow reactor.The results revealed that the decomposition of tungstophosphoric acid into its constituent oxides as crystalline WO3 and phosphorus oxide on the surface of ZrO2.Pt/HPW/ZrO2 catalysts showed the excellent activity in the reaction of deoxygenation of glycerol into 1,3-propandiol.The glycerol conversion and the yield of 1,3-PDO greatly depended on Pt content,HPW/ZrO2 calcination temperature,reaction temperature,and pressure and glycerol concentration in aqueous solution.Under the conditions of 130 ℃,4 MPa,aqueous glycerol(60% w/w) LHSV=0.25 h-1,the conversion of glycerol over 2.0% Pt/HPWZ10(700) was 53.4%,and the selectivity to 1,3-PDO was up to 44.5%(1,3-PDO/1,2-PDO=14.3 molar ratio).The catalyst was stable for 100 h under operation conditions.