Since the diesel products from paraffin-based Daqing crude oil showed low sensitivity to certain commercial diesel pour point depressant （PPDs） that resulted from the high content of paraffin, certain poly-acrylic a...Since the diesel products from paraffin-based Daqing crude oil showed low sensitivity to certain commercial diesel pour point depressant （PPDs） that resulted from the high content of paraffin, certain poly-acrylic acid derivatives （PADE） with-COOR, -COOH,-CONHR, and -COO-NH3^＋R groups by molecular design on the mechanics of diesel; PPDs were synthesized and evaluated as cold flow improver for Daqing 0^# diesel in this paper. The pure PADE was superior to the commercial PPDs and displayed a substantial ability of wax crystals dispersion. There was a synergistic effect among the PADE and T1804 and secondary amine. The synergism clearly improved the low temperature performance of Daqing diesel products and could reduce the cold filter plugging point of 0^# diesel by 6-7 ℃.展开更多
In the practice of petroleum industry, adding cold flow improver （CFI） to lower the fuel＇s cold filter plugging point （CFPP） is an effective and economic way for improving the cold flow performance of diesel fuel...In the practice of petroleum industry, adding cold flow improver （CFI） to lower the fuel＇s cold filter plugging point （CFPP） is an effective and economic way for improving the cold flow performance of diesel fuel. This paper described the synthesis and evaluation of the performance of dibehenyl fumarate-vinyl acetate （FV） copolymer for improving the cold flow performance of the tested diesel fuels. The carbon distribution in n-alkanes of the tested diesel samples were analyzed by gas phase chromatography. The structure of the copolymer was confirmed by the 1H NMR spectroscopy. The wax crystals morphologies with and without adding the FV additive were investigated by means of polarizing microscope. The test results indicated that the FV additive could depress CFPP of the tested diesel samples by 2℃ and 4℃, respectively, when dosage of the additive was 0.08 m%. The additive can modify the size and shape of the wax crystals and inhibit the formation of larger wax crystal lattices.展开更多
Precipitation of nalkanes in diesel affects cold flow property With XRD pattern, shape of crystals is able to be studied But XRD pattern has not been applied to investigation of precipitation of crystals of n...Precipitation of nalkanes in diesel affects cold flow property With XRD pattern, shape of crystals is able to be studied But XRD pattern has not been applied to investigation of precipitation of crystals of nalkanes appearing in diesel In this paper, XRD pattern of a series of diesel flow improver(DFI), wax and mixture of wax and DFI are analyzed The relationship between character of XRD pattern and performance of DFI is studied When sharp peak between 10°～30° is little, shape of peak is ordered and curve of peak is smooth, performance of DFI is better XRD pattern of the mixture of wax and DFI shows noncrystalline structure has changed Hence it might be considered crystallization procedure of wax be affected by DFI This work is also helpful to the full understanding of the mechanism of展开更多
The improvement of the Cold Filter Plugging Point (CFPP) by an additive will depend on either the characteristics of the diesel or the additive itself. The ways in which cold flow improver interacts with the constitue...The improvement of the Cold Filter Plugging Point (CFPP) by an additive will depend on either the characteristics of the diesel or the additive itself. The ways in which cold flow improver interacts with the constituents of the fuels and the reasons for their efficiencies are far from fully elucidated. In this work , the contents of the n-paraffin in five kinds of diesels were tested by urea adduction, and the carbon distribution of n-paraffins was tested by temperature programmed gas chromatograph GC-14A and computed by the software for simulating distillation. Maximum likelihood method is applied to obtain μ and σ2 of the carbon distribution, and the deviation χ2 is computed. When the degrees of freedom is 4 and significance level (α) is 0.10, χ2_ 0.90(4)=7.779. If deviation χ2 is smaller than χ2_ 0.90(4), the hypothesis that the population is normal is accepted. The results show that the distributions of n-paraffin in these five kinds of diesels are normal. It can be found that the susceptibility of the diesel DQCH is weak and the variance σ2 of the carbon distribution in n-paraffin is only 1076.21 smaller than that for other diesels. The smaller the variance σ2 is, the weaker the susceptibility is. The susceptibility of the diesel LYL is also weak. The value of the statistic test quantity χ2 on the normal distribution of the n-paraffin in the diesel LYL is 4.112 bigger than other diesels . Statistic test quantity χ2 could reflect whether the carbon distribution of n-paraffin fits the normal distribution. When the carbon distribution of n-paraffin does not fit normal well, the wax settling does not match the agglomeration of flow improver. In this situation, the flow improver can’t interact with more wax crystal so that the CFPP of diesel can not be decreased.展开更多
文摘Since the diesel products from paraffin-based Daqing crude oil showed low sensitivity to certain commercial diesel pour point depressant （PPDs） that resulted from the high content of paraffin, certain poly-acrylic acid derivatives （PADE） with-COOR, -COOH,-CONHR, and -COO-NH3^＋R groups by molecular design on the mechanics of diesel; PPDs were synthesized and evaluated as cold flow improver for Daqing 0^# diesel in this paper. The pure PADE was superior to the commercial PPDs and displayed a substantial ability of wax crystals dispersion. There was a synergistic effect among the PADE and T1804 and secondary amine. The synergism clearly improved the low temperature performance of Daqing diesel products and could reduce the cold filter plugging point of 0^# diesel by 6-7 ℃.
基金supported by the Basic Research Program of the State Key Laboratory of Heavy Oil Processing(200310),China University of Petroleum,Beijing,China.
文摘In the practice of petroleum industry, adding cold flow improver （CFI） to lower the fuel＇s cold filter plugging point （CFPP） is an effective and economic way for improving the cold flow performance of diesel fuel. This paper described the synthesis and evaluation of the performance of dibehenyl fumarate-vinyl acetate （FV） copolymer for improving the cold flow performance of the tested diesel fuels. The carbon distribution in n-alkanes of the tested diesel samples were analyzed by gas phase chromatography. The structure of the copolymer was confirmed by the 1H NMR spectroscopy. The wax crystals morphologies with and without adding the FV additive were investigated by means of polarizing microscope. The test results indicated that the FV additive could depress CFPP of the tested diesel samples by 2℃ and 4℃, respectively, when dosage of the additive was 0.08 m%. The additive can modify the size and shape of the wax crystals and inhibit the formation of larger wax crystal lattices.
文摘Precipitation of nalkanes in diesel affects cold flow property With XRD pattern, shape of crystals is able to be studied But XRD pattern has not been applied to investigation of precipitation of crystals of nalkanes appearing in diesel In this paper, XRD pattern of a series of diesel flow improver(DFI), wax and mixture of wax and DFI are analyzed The relationship between character of XRD pattern and performance of DFI is studied When sharp peak between 10°～30° is little, shape of peak is ordered and curve of peak is smooth, performance of DFI is better XRD pattern of the mixture of wax and DFI shows noncrystalline structure has changed Hence it might be considered crystallization procedure of wax be affected by DFI This work is also helpful to the full understanding of the mechanism of
文摘The improvement of the Cold Filter Plugging Point (CFPP) by an additive will depend on either the characteristics of the diesel or the additive itself. The ways in which cold flow improver interacts with the constituents of the fuels and the reasons for their efficiencies are far from fully elucidated. In this work , the contents of the n-paraffin in five kinds of diesels were tested by urea adduction, and the carbon distribution of n-paraffins was tested by temperature programmed gas chromatograph GC-14A and computed by the software for simulating distillation. Maximum likelihood method is applied to obtain μ and σ2 of the carbon distribution, and the deviation χ2 is computed. When the degrees of freedom is 4 and significance level (α) is 0.10, χ2_ 0.90(4)=7.779. If deviation χ2 is smaller than χ2_ 0.90(4), the hypothesis that the population is normal is accepted. The results show that the distributions of n-paraffin in these five kinds of diesels are normal. It can be found that the susceptibility of the diesel DQCH is weak and the variance σ2 of the carbon distribution in n-paraffin is only 1076.21 smaller than that for other diesels. The smaller the variance σ2 is, the weaker the susceptibility is. The susceptibility of the diesel LYL is also weak. The value of the statistic test quantity χ2 on the normal distribution of the n-paraffin in the diesel LYL is 4.112 bigger than other diesels . Statistic test quantity χ2 could reflect whether the carbon distribution of n-paraffin fits the normal distribution. When the carbon distribution of n-paraffin does not fit normal well, the wax settling does not match the agglomeration of flow improver. In this situation, the flow improver can’t interact with more wax crystal so that the CFPP of diesel can not be decreased.
