The thermal degradation of two synthetic lubricants base oils, poly-a-olefins （PAO） and di-esters （DE）, was investigated under oxidative pyrolysis condition and their properties were characterized in simulated ＂a...The thermal degradation of two synthetic lubricants base oils, poly-a-olefins （PAO） and di-esters （DE）, was investigated under oxidative pyrolysis condition and their properties were characterized in simulated ＂areo-engine＂ by comparing the thermal stability and identifying the products of thermal decomposition as a function of exposure temperature. The characterization of the products were performed by means of Fourier transform infrared spectrometry （FTIR）, gas chromatography/mass spectrometry （GC/MS） and viscosity experiments. The results show that PAO has the lower thermal stability, being degraded at 200℃ different from 300 ℃ for DE. Several by-products are identified during the thermal degradation of two lubricant base oils. The majority of PAO products consist of alkenes and olefins, while more oxygen-contained organic compounds are detected in DE samples based on GC/MS analysis. The related reaction mechanisms are discussed based on the experimental results.展开更多
The production of poly-α-olefins(PAOs)has attracted attention due to their excellent viscosity-temperature dependence,wear characteristics,oxidative properties,and high thermal stability.In this study,indene extracte...The production of poly-α-olefins(PAOs)has attracted attention due to their excellent viscosity-temperature dependence,wear characteristics,oxidative properties,and high thermal stability.In this study,indene extracted during coal tar refining was used as a raw material to synthesize a bis(indenyl)zirconium dichloride metallocene catalyst.A PAO with low viscosity and a high viscosity index was produced via the oligomerization of 1-decene in the presence of both the prepared metallocene and a methylaluminoxane(MAO)co-catalyst.Notably,the effects of different synthesis reaction parameters,such as Al:Zr ratio,amount of catalyst,and reaction temperature,on the conversion ratio and product selectivity were investigated in detail.The produced PAO was thoroughly characterized using Fourier-transform infrared,^(13)C,and^(1)H nuclear magnetic resonance spectroscopies;gas chromatography;and viscosity measurements.At 70℃,the metallocene catalyst created more stable active sites.In addition,the alkylation effect of MAO was noticeable.Interestingly,the obtained catalysis results demonstrated that a high conversion ratio of~93%was achieved at a low reaction temperature of 70℃,with a catalyst dosage of 0.0848 mmol and Al:Zr ratio of 8.48mmol:0.0848mmol.Moreover,under these optimal conditions,the kinematic viscosity of PAO was 4.25 mm2/s at 100℃,and the viscosity index was 139,indicating good viscosity-temperature properties.展开更多
Polymerization of mixed alpha-olefins originating from the Fischer-Tropsch synthesis catalyzed by theBu)_3/[Me_2NHPh]^+[B(C_6F_5)_4]^-,was studied.The effects of the Zr/olefin mole ratio,Al/Zr mole ratio,reaction temp...Polymerization of mixed alpha-olefins originating from the Fischer-Tropsch synthesis catalyzed by theBu)_3/[Me_2NHPh]^+[B(C_6F_5)_4]^-,was studied.The effects of the Zr/olefin mole ratio,Al/Zr mole ratio,reaction temperature,and reaction time on the viscosity and molecular weight of the product were investigated.The conversion under optimized conditions reached 97.3%.The product structure was characterized by ^(13)C NMR spectrometry and ~1H NMR spectrometry,and the conversion of olefins with different carbon numbers under different conditions was determined by GC analysis.The polymer obtained under optimized conditions has a high viscosity index of 262 with a narrow molecular weight distribution of 1.95,which is a desired component for lubricating base oil.展开更多
基金Supported by the Fund from the Air Force Armament Department of China for Innovative Research Group(Grant KJ2012283)
文摘The thermal degradation of two synthetic lubricants base oils, poly-a-olefins （PAO） and di-esters （DE）, was investigated under oxidative pyrolysis condition and their properties were characterized in simulated ＂areo-engine＂ by comparing the thermal stability and identifying the products of thermal decomposition as a function of exposure temperature. The characterization of the products were performed by means of Fourier transform infrared spectrometry （FTIR）, gas chromatography/mass spectrometry （GC/MS） and viscosity experiments. The results show that PAO has the lower thermal stability, being degraded at 200℃ different from 300 ℃ for DE. Several by-products are identified during the thermal degradation of two lubricant base oils. The majority of PAO products consist of alkenes and olefins, while more oxygen-contained organic compounds are detected in DE samples based on GC/MS analysis. The related reaction mechanisms are discussed based on the experimental results.
基金supported by the Chinese Academy of Sciences Strategic Pilot Science and Technology Special (Class A)(XDA21020000)the National Natural Science Foundation of China (22072175,21673272)support from the Ulam program,awarded by the Polish National Agency for Academic Exchange (NAWA),Poland,under project No.PPN/ULM/2020/1/00006/DEC/1
文摘The production of poly-α-olefins(PAOs)has attracted attention due to their excellent viscosity-temperature dependence,wear characteristics,oxidative properties,and high thermal stability.In this study,indene extracted during coal tar refining was used as a raw material to synthesize a bis(indenyl)zirconium dichloride metallocene catalyst.A PAO with low viscosity and a high viscosity index was produced via the oligomerization of 1-decene in the presence of both the prepared metallocene and a methylaluminoxane(MAO)co-catalyst.Notably,the effects of different synthesis reaction parameters,such as Al:Zr ratio,amount of catalyst,and reaction temperature,on the conversion ratio and product selectivity were investigated in detail.The produced PAO was thoroughly characterized using Fourier-transform infrared,^(13)C,and^(1)H nuclear magnetic resonance spectroscopies;gas chromatography;and viscosity measurements.At 70℃,the metallocene catalyst created more stable active sites.In addition,the alkylation effect of MAO was noticeable.Interestingly,the obtained catalysis results demonstrated that a high conversion ratio of~93%was achieved at a low reaction temperature of 70℃,with a catalyst dosage of 0.0848 mmol and Al:Zr ratio of 8.48mmol:0.0848mmol.Moreover,under these optimal conditions,the kinematic viscosity of PAO was 4.25 mm2/s at 100℃,and the viscosity index was 139,indicating good viscosity-temperature properties.
文摘Polymerization of mixed alpha-olefins originating from the Fischer-Tropsch synthesis catalyzed by theBu)_3/[Me_2NHPh]^+[B(C_6F_5)_4]^-,was studied.The effects of the Zr/olefin mole ratio,Al/Zr mole ratio,reaction temperature,and reaction time on the viscosity and molecular weight of the product were investigated.The conversion under optimized conditions reached 97.3%.The product structure was characterized by ^(13)C NMR spectrometry and ~1H NMR spectrometry,and the conversion of olefins with different carbon numbers under different conditions was determined by GC analysis.The polymer obtained under optimized conditions has a high viscosity index of 262 with a narrow molecular weight distribution of 1.95,which is a desired component for lubricating base oil.
