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Sheng Han - One of the best experts on this subject based on the ideXlab platform.

  • research on combined Pour Point Depressant of methacrylate acrylamide copolymers and ethylene vinyl acetate copolymers for diesel fuel
    Fuel, 2021
    Co-Authors: Hualin Lin, Yuan Xue, Sheng Han, Suya Yin
    Abstract:

    Abstract The combined-Pour Point Depressants (PPDs) have shown potential for the improvement of the cold flow properties of diesel. In this study, free radical polymerization was used to polymerize methacrylate (RMC) and acrylamide (AM) in different molar ratios (1:1, 3:1, 6:1, 9:1, 12:1, 15:1). Methacrylate-acrylamide copolymers (RMC-AM) were synthesized and analyzed through Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), and thermogravimetric analysis (TGA) to characterize the copolymers. Through exploring the effect of different chain lengths and different monomer molar ratios on the solid Point (SP) and cold filter-plugging Point (CFPP) of diesel, C14MC-AM (9:1) showed relatively good performance (ΔSP = 25 °C, ΔCFPP = 10 °C). Then, ethylene–vinyl acetate copolymer (EVA) materials with different VA content were introduced in this study. Diesel treated with 1000 ppm of EVA-2 (VA = 28%) showed relatively good performance (ΔSP = 18 °C, ΔCFPP = 10 °C). C14MC-AM (9:1) was mixed with EVA −2 in different ratios (1:0, 4:1, 2:1, 1:1, 1:2, 1:4, and 0:1, namely, PPDC-1 ~ 7) to produce synergy and improve the cold flow properties of diesel. The ΔSP and ΔCFPP of diesel fuel treated with only 500 ppm PPDC-5 can reach 28 °C and 23 °C, respectively. In addition, the crystallization behavior and crystal morphology of the treated diesel fuel were discussed through differential scanning calorimeter, polarized optical microscope and rheological analysis. The results showed that the combined-PPD made the wax crystals dissolve in the diesel system. The wax crystals became more uniform and denser under the action of AM polar groups.

  • synthesis and evaluation of benzyl methacrylate methacrylate copolymers as Pour Point Depressant in diesel fuel
    Fuel, 2019
    Co-Authors: Maiying Xie, Yuan Xue, Hualin Lin, Fengfei Chen, Jinbao Liu, Taishun Yang, Suya Yin, Sheng Han
    Abstract:

    Abstract The cold-flow properties of diesel fuel are considered as the determining factors of diesel utilization and popularization. Pour-Point Depressants (PPDs) are often added to diesel to remediate issues with fluidity in cold climates. In this study, a series of benzyl methacrylate-methacrylate copolymers (MB-R1MC, R1 = C12, C14, C16, C18) and benzyl methacrylate-tetradecyl methacrylate (MB-C14MC) in different molar ratios of the functional monomers (1:1, 1:5, 1:10, 1:15, and 1:20) was synthesized by radical polymerization and characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). The depression effects of these PPDs in diesel were investigated and compared with previous reports. Results showed that diesel treated with 3000 ppm MB-C14MC (1:10) exhibited the best depression on solid Point and cold filter-plugging Point (CFPP) by 26 and 12 °C, respectively, and the CFPP depression was evidently superior to that in a previous research. Moreover, the action mechanism was explored by differential scanning calorimeter, polarizing optical microscopy and rheology analysis. Results showed that the nonpolar component of PPDs co-crystallized with n-alkanes and provided large number of crystallization sites in diesel, whereas the polar components adsorbed on the wax crystal surface, thereby changing the shape, decreasing the size, and increasing the dispersity of wax crystal. Therefore, MB-C14MC copolymer was confirmed to be an excellent PPD of diesel fuel.

  • influence of poly methacrylate co maleic anhydride Pour Point Depressant with various pendants on low temperature flowability of diesel fuel
    Fuel, 2018
    Co-Authors: Yuan Xue, Zhicheng Zhao, Xiang Lian, Hualin Lin, Sheng Han
    Abstract:

    Abstract To investigate the influence of various pendants in comb-type copolymers on the low-temperature flowability of diesel fuel, a series of methacrylate-co-maleic anhydride copolymers R1MC-MA (R1 = C14, C16, C18) were synthesized. And C14MC-MA was aminated by R2NH2 (R2 = C14, C16, C18, phenyl, 1-naphthyl) to obtain a series of aminated copolymers C14MC-MA-a (C14MC-MA-14a, C14MC-MA-16a, C14MC-MA-18a, C14MC-MA-phenylamine, C14MC-MA-naphthylamine). They were characterized by Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC). The influence of these Pour Point Depressants (PPDs) on the cold flow properties of diesel fuel were investigated. The crystallization behavior and crystal morphology of diesel fuel were also studied by differential scanning calorimeter (DSC) and polarizing optical microscope (POM). When the dosage of PPDs was 1000 ppm, C14MC-MA-14a displayed an excellent depression on cold filter plugging Point (CFPP) by 5 °C, C14MC-MA-phenylamine showed the best depression on solid Point (SP) by 17 °C, and PPDC-1 (the mixture of C14MC-MA-14a with C14MC-MA-phenylamine) exhibited the best performance in depressing the CFPP and SP by 8 °C and 18 °C respectively. The results show that the effects of the PPDs on reducing SP and CFPP sometimes are inconsistent, because SP is closely related to the crystal/liquid interface, while CFPP is directly related to the wax crystal size. When Pour Point Depressants are added, the wax crystals become smaller and regular (act as wax dispersants), thus inhibiting the formation of the porous network. So the CFPP decreased with decreasing the wax crystal size; and the SP first decreased with decreasing the wax crystal size, while when the wax crystals are too small, the large specific surface energy leads to the recovery of the SP. DSC and POM results showed that PPDs changed the crystallization behavior, size and shape of wax crystals, weakened the ability of wax crystals to form a three-dimensional network structure and made the wax crystals more uniform, compact, and dense. Therefore, the low temperature flowability of diesel fuel is improved by the synthesized Pour Point Depressant.

  • A new kind of nanohybrid poly(tetradecyl methyl-acrylate)-graphene oxide as Pour Point Depressant to evaluate the cold flow properties and exhaust gas emissions of diesel fuels
    Fuel, 2018
    Co-Authors: Zhicheng Zhao, Yuan Xue, Yan Song, Lian Jun, Chang Wei, Sheng Han
    Abstract:

    Abstract In this paper, a new kind of nanohybrid poly(tetradecyl methyl-acrylate)-graphene oxide (PMA14-GO) as Pour Point Depressant (PPD) was prepared from graphene oxide, using matrix via in situ free radical polymerization. The effect of PMA14-GO (i.e., PMA14-3GO, PMA14-6GO and PMA14-9GO) PPDs on the cold flow properties and exhaust gas emissions of diesel fuels were studied. Results indicated that PMA14-GO PPDs exhibited a better effect on cold filter plugging Point (CFPP) and solidifying Point (SP) than that of PMA14. Among them, PMA14-6GO and PMA14-9GO were the most suitable candidates for improving CFPP and SP. Specifically, upon addition of 0.2 wt% PMA14-6GO could reduce the CFPP of diesel by 14 °C, and 0.2 wt% PMA14-9GO reduced the SP of diesel by 19 °C. Moreover, PMA14-GO PPDs could effectively lower the low-temperature. Other fuel properties were also determined and compared with the ASTM D975 . Given the heterogeneous nucleation mechanism, uniform and tiny particle-shaped crystals were observed by polarizing optical microscopy and differential scanning calorimetry. In addition, burning diesel fuel with PMA14-GO PPDs effectively reduced HC and CO emissions, whereas NO and CO2 emissions increased with the increased engine speed at full load.

  • a new kind of Pour Point Depressant diesel from direct coal liquefaction
    Fuel Processing Technology, 2016
    Co-Authors: Hui Liu, Sheng Han, Shuangshuang Jiang, Hongshuang Guo, Chao Yang, Jianzhong Jiang
    Abstract:

    Abstract Coal liquefaction (CL) technology is a feasible solution to the energy crisis. The coal-to-liquid conversion includes direct CL (DCL) and indirect CL. Compared with the limited and unevenly distributed petroleum resources, the diesel from DCL (DDCL) has received worldwide attention since the beginning of this century and has been considered a substitute for diesel fuel. In this study, DDCL was regarded as a potential additive to improve the cold flow properties of petrodiesel. Other properties of the blending were also evaluated. When 40% DDCL was added to petrodiesel, the Pour Point (PP) reached − 31 °C, and the cold filter plugging Point (CFPP) reached − 15 °C. The ΔPP and ΔCFPP decreased by 24 and 13 °C, respectively. The other properties, such as flash Point and water content were not affected with the addition of DDCL. The cetane number of the blending were decreased but can be solved by adding fatty acid esters easily. The blending could be used in most climatic zones in the world, except the polar regions. In addition, Crystallization behavior was investigated via differential scanning calorimetry (DSC), and find that petrodiesel blended with 40% DDCL is more stable than blended with 10% and 20% DDCL.

Xiaodong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and evaluation of grafted eval as Pour Point Depressant for waxy crude oil
    Industrial & Engineering Chemistry Research, 2018
    Co-Authors: Yongwen Ren, Long Fang, Zhaojun Chen, Xiaodong Zhang
    Abstract:

    Alcoholized ethylene–vinyl acetate copolymer (EVAL) was chemically modified by grafting n-alkyl acrylates with different alkyl chain lengths. The grafted EVAL was characterized through Fourier transform infrared (FTIR) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, and element analysis. The effect of grafted EVAL on wax crystallization process of crude oil was investigated by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The results showed that the length of alkyl side-chain in grafted EVAL largely influenced the efficiency of grafted EVAL. Grafted EVAL with side-chain length of C16 could reduce the Pour Point of Shengli (SL) crude oil by 11 °C, and that with side-chain length of C18 could reduce the Pour Point of Jianghan (JH) crude oil by 14.5 °C. The introduction of alkyl side-chain could improve wax solubility and promote grafted EVAL to adsorb and cocrystallize with wax molecules, which obviously decreased the wax precipitation amount and cha...

  • preparation and evaluation of modified ethylene vinyl acetate copolymer as Pour Point Depressant and flow improver for jianghan crude oil
    Industrial & Engineering Chemistry Research, 2017
    Co-Authors: Yongwen Ren, Long Fang, Zhaojun Chen, Xiaodong Zhang
    Abstract:

    The ethylene–vinyl acetate copolymer (EVA) was modified by alkali-catalyzed alcoholysis. The alcoholized EVA (EVAL) was characterized by Fourier transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance (1H NMR). Moreover, the influence of modified polar groups of EVA on the crystallization process of wax was investigated through differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The results showed that EVAL had better performance than EVA in reducing the Pour Point and the viscosity of crude oil. EVAL could change the wax crystal habit and obviously lower the wax precipitation amount of crude oil. In addition, EVAL with stronger polarity could provide greater electrostatic repulsion force to wax crystals compared with EVA, which made the wax crystals have more difficulty to connect together and form a much looser network structure.

  • preparation of a kind of reactive Pour Point Depressant and its action mechanism
    Fuel, 2015
    Co-Authors: Tao Liu, Long Fang, Xin Liu, Xiaodong Zhang
    Abstract:

    Abstract A series of reactive Pour Point Depressants (PPD) with anhydride group were prepared, and their action mechanism had been investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and cross-polarized light microscope. The results showed that the prepared Pour Point Depressants had obvious Pour Point depressing effect on crude oil. Its action mechanism was concluded that PPD could react with the resin and asphaltene in the crude oil to generate a new macromolecule when crude oil was treated with PPD-3 at 90 °C. The new macromolecule further formed a new agglomerate structure by association with the asphaltene and resin in crude oil, which worked as a new nucleator to provide nucleation sites for wax crystal instead of the original asphaltene–resin agglomerate structure, and then improved the flowability of crude oil.

  • investigation into a Pour Point Depressant for shengli crude oil
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Long Fang, Xiaodong Zhang, Botao Zhang
    Abstract:

    A new-style Pour Point Depressant (PPD) for crude oil was prepared by mixing the aminated copolymer and the composite commercial ethylene–vinyl acetate copolymers (EVA) in fixed proportion. The ami...

  • investigation into a Pour Point Depressant for shengli crude oil
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Long Fang, Xiaodong Zhang, Botao Zhang
    Abstract:

    A new-style Pour Point Depressant (PPD) for crude oil was prepared by mixing the aminated copolymer and the composite commercial ethylene–vinyl acetate copolymers (EVA) in fixed proportion. The aminated copolymer was synthesized by amination of terpolymer copolymerized with monomers octadecyl acrylate, maleic anhydride, and vinyl acetate. Moreover, the aminated copolymer was characterized by Fourier transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (1H NMR), and gel permeation chromatography (GPC). The interaction between components of the crude oil and the PPD was investigated by FTIR, differential scanning calorimetry (DSC), and cross-polarized light microscopy. The results showed that the PPD could form asphaltene–PPD–resin agglomerates. The new agglomerates became the efficient nucleator of the crude oil beneficiated with PPD. They changed the process of wax crystallization and greatly depressed the Pour Point of the crude oil.

Yang Liu - One of the best experts on this subject based on the ideXlab platform.

Guangyu Sun - One of the best experts on this subject based on the ideXlab platform.

  • ethylene vinyl acetate copolymer and resin stabilized asphaltenes synergistically improve the flow behavior of model waxy oils 2 effect of asphaltene content
    Energy & Fuels, 2018
    Co-Authors: Bo Yao, Fei Yang, Xiaoping Zhang, Guangyu Sun, Gang Liu, Yansong Zhao
    Abstract:

    In part 1 (10.1021/acs.energyfuels.7b03657), the synergistic effect of ethylene–vinyl acetate copolymer (EVA) Pour Point Depressant (PPD) and rensin-stabilized asphaltenes on improving the flowability of synthetic waxy oil has been verified. This paper is a continuous work studying the effect of the asphaltene content (0.01–3 wt %) on the synergistic effect between EVA PPD and resin-stabilized asphaltenes. The results showed that, in the absence of EVA and with the increase of the asphaltene content, the precipitated wax crystals of the waxy oil tend to grow gradually from initial big needle-like to smaller and more regular (spherical-like) particles with a larger amount; therefore, adding aphaltenes can only decrease the apparent viscosity of waxy oil at the temperature range slightly lower than the wax precipitation temperature (WPT) (the precipitated wax crystal amount is low), and the temperature range is broadened by increasing the asphaltene content. When the temperature is decreased far below the W...

  • performance improvement of the ethylene vinyl acetate copolymer eva Pour Point Depressant by small dosage of the amino functionalized polymethylsilsesquioxane pamsq microsphere
    Fuel, 2018
    Co-Authors: Bo Yao, Fei Yang, Xiaoping Zhang, Guangyu Sun, Yansong Zhao
    Abstract:

    Abstract In the previous work, we have reported that small dosages of the polymethylsilsesquioxane (PMSQ) microsphere can effectively improve the performance of the EVA Pour Point Depressant (PPD) and the amount of EVA PPD adsorbed on the microsphere evidently influences the efficiency of the EVA/PMSQ composite particle. To further promote the adsorption of EVA on the microsphere and enhance the efficiency of the composite particle, here, the amino-functionalized PMSQ microspheres with different amino molar ratios (PAMSQ) are first synthesized and characterized. The flow behavior, exothermic crystallization and microstructure of the waxy crude oil undoped/doped with EVA, EVA/PMSQ and EVA/PAMSQ are systemically investigated. Results show that 50 ppm EVA PPD can greatly improve the flow behavior of the oil and small dosages (2.5 ppm) of PMSQ microsphere can significantly improve the performance of the EVA PPD. After the amino-functionalization, the flow improving efficiency of EVA/PAMSQ is further enhanced: the gelation Point, G′, G″, apparent viscosity and yield stress of the oil sample decrease to a lower value. The best performance is found at adding 50 ppm EVA + 2.5 ppm PAMSQ-2 (with amino molar ratios at 15%). Compared to EVA/PMSQ, the EVA/PAMSQ exhibits a stronger nucleation effect to increase the WAT of the oil sample slightly, and outstandingly modifies the morphology of the precipitated wax crystals into larger and more compact flocs. The amino-functionalization facilitates more EVA PPDs adsorbing and concentrating on the PAMSQ microsphere, causing the formation of the EVA/PAMSQ composite particles. The composite particles provide stronger nucleation effect for the wax precipitation, resulting in larger and more compact wax microstructures and then further improving the flow behavior of the oil. The rheological improving performance of EVA/PAMSQ for the waxy crude oil increases with the increase of amino molar ratio and the efficiency of EVA/PAMSQ-2 reaches the best. When the amino molar ratio is too high (PMASQ-3), the PAMSQ-3 microsphere is unstable in oil phase and aggregates into large particle flocs, which inhibits the EVA adsorption on the PAMSQ-3 microsphere and then weakens the rheological improving efficiency of the EVA/PAMSQ-3 composite particle.

  • performance improvement of the ethylene vinyl acetate copolymer eva Pour Point Depressant by small dosages of the polymethylsilsesquioxane pmsq microsphere an experimental study
    Fuel, 2017
    Co-Authors: Fei Yang, Bo Yao, Xin Shi, Guangyu Sun
    Abstract:

    Abstract In a previous work, the addition of the polymethylsilsesquioxane (PMSQ) microsphere (50–400 ppm) can improve the flow behavior of waxy crude oil through the spacial hindrance effect. However, the flow improving efficiency of the neat PMSQ microsphere is not as good as the traditional polymeric Pour Point Depressants (PPDs). In this paper, the effect of the ethylene-vinyl acetate copolymer (EVA2806) PPD together with the PMSQ microsphere (with the size around 2 µm) on the flow behavior of a typical waxy crude oil was investigated. The results show that adding 50 ppm EVA PPD can greatly improve the flow behavior of the oil. The neat PMSQ microsphere cannot improve the flow behavior of the oil at small dosages (≤10 ppm), but can significantly improve the performance of the EVA PPD. The gelation Point, G′, G″, transient apparent viscosity and yield stress of the oil decrease further after adding both 50 ppm EVA and a small amount of the PMSQ microsphere (≤10 ppm). The best flow improving efficiency is found at 50 ppm EVA + 2.5 ppm PMSQ. The addition of the PMSQ microsphere has little influence on the WAT and precipitated wax crystal amount of the oil doped with EVA, but outstandingly changes the morphology of the precipitated wax crystals into larger and more compact flocs. The adsorption tests show that the EVA molecules can adsorb and concentrate on the PMSQ microsphere, thus causing the formation of the EVA/PMSQ composite particles. The composite particles can act as nucleation templates for the wax precipitation, resulting in larger and more compact wax microstructures and then further improving the flow behavior of the oil. The PMSQ microsphere dosage and the amount of EVA PPD adsorbed on the microsphere obviously influence the performance of the composite particle with the best performance at 50 ppm EVA + 2.5 ppm PMSQ. The findings mentioned above provide a new way to improve the performance of polymeric PPDs efficiently.

  • structural properties of gelled changqing waxy crude oil benefitted with nanocomposite Pour Point Depressant
    Fuel, 2016
    Co-Authors: Bo Yao, Fei Yang, Ying Zhang, Zuoqu Xiao, Guangyu Sun
    Abstract:

    Abstract The novel and effective nanocomposite PPD has garnered attention for its potential application in pipelines transporting waxy crude oil. In this paper, melt blending method was used here to prepare the poly(octadecyl acrylate) (POA)/clay nanocomposite PPD, which shows much better performance on waxy crude oil. The effects of the POA and POA/clay nanocomposite PPDs on the structural properties of gelled Changqing waxy crude oil were well studied through rheological tests, DSC analyses and microscopic observation. The precipitated wax crystal amount of the crude oil at low temperatures does not change with the addition of POA and nanocomposite PPDs, but the addition greatly weakens the structure of the gelled crude oil. Compared with the same dosage of POA, the addition of nanocomposite PPD further inhibits the formation of wax crystal’s network and further weakens the structural strength and viscoelasticity of the gelled crude oil. Increasing the dosage of nanocomposite PPD favors the weakening of the gelled crude oil structure. The nanocomposite PPD particles can act as nucleation templates of wax crystals and further weaken the gelled structure of waxy crude oil. In addition, we deduce that controlling the dispersed state of polymeric PPDs in oil phase could control the performance of the polymeric PPDs. The decrease of the mean nanocomposite PPD particle size from 6 μm (prepared by solvent blending) to 2 μm (prepared by melt blending) changes the dispersed state of POA molecules in oil phase and thus greatly enhances the performance of nanocomposite PPD.

  • influences of different functional groups on the performance of polyoctadecyl acrylate Pour Point Depressant
    Petroleum Science and Technology, 2016
    Co-Authors: Fei Yang, Bo Yao, Guangyu Sun, Zuoqu Xiao, Lu Wang, Xin Shi, Kongyao Yan
    Abstract:

    ABSTRACTThe polyoctadecyl acrylate (POA), polyoctadecyl acrylate-vinyl acetate (POA-VA), polyoctadecyl acrylate-maleic anhydride (POA-MA), and polyoctadecyl acrylate-styrene (POA-St) were synthesized and used as Pour Point Depressants (PPDs). The performance of the PPDs first increases with the increase of polar group (MA or VA) content, and then decreases with the further increase of polar group (MA or VA) content. The POA-VA PPDs show the best performance at the OA:VA molar ratio 3:1, whereas the POA-MA PPDs shows the best performance at the OA:MA molar ratio 7:1. The performance of POA-St PPDs decreases outstandingly with the increase of the nonpolar St molar fraction.

Yuan Xue - One of the best experts on this subject based on the ideXlab platform.

  • research on combined Pour Point Depressant of methacrylate acrylamide copolymers and ethylene vinyl acetate copolymers for diesel fuel
    Fuel, 2021
    Co-Authors: Hualin Lin, Yuan Xue, Sheng Han, Suya Yin
    Abstract:

    Abstract The combined-Pour Point Depressants (PPDs) have shown potential for the improvement of the cold flow properties of diesel. In this study, free radical polymerization was used to polymerize methacrylate (RMC) and acrylamide (AM) in different molar ratios (1:1, 3:1, 6:1, 9:1, 12:1, 15:1). Methacrylate-acrylamide copolymers (RMC-AM) were synthesized and analyzed through Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), and thermogravimetric analysis (TGA) to characterize the copolymers. Through exploring the effect of different chain lengths and different monomer molar ratios on the solid Point (SP) and cold filter-plugging Point (CFPP) of diesel, C14MC-AM (9:1) showed relatively good performance (ΔSP = 25 °C, ΔCFPP = 10 °C). Then, ethylene–vinyl acetate copolymer (EVA) materials with different VA content were introduced in this study. Diesel treated with 1000 ppm of EVA-2 (VA = 28%) showed relatively good performance (ΔSP = 18 °C, ΔCFPP = 10 °C). C14MC-AM (9:1) was mixed with EVA −2 in different ratios (1:0, 4:1, 2:1, 1:1, 1:2, 1:4, and 0:1, namely, PPDC-1 ~ 7) to produce synergy and improve the cold flow properties of diesel. The ΔSP and ΔCFPP of diesel fuel treated with only 500 ppm PPDC-5 can reach 28 °C and 23 °C, respectively. In addition, the crystallization behavior and crystal morphology of the treated diesel fuel were discussed through differential scanning calorimeter, polarized optical microscope and rheological analysis. The results showed that the combined-PPD made the wax crystals dissolve in the diesel system. The wax crystals became more uniform and denser under the action of AM polar groups.

  • synthesis and evaluation of benzyl methacrylate methacrylate copolymers as Pour Point Depressant in diesel fuel
    Fuel, 2019
    Co-Authors: Maiying Xie, Yuan Xue, Hualin Lin, Fengfei Chen, Jinbao Liu, Taishun Yang, Suya Yin, Sheng Han
    Abstract:

    Abstract The cold-flow properties of diesel fuel are considered as the determining factors of diesel utilization and popularization. Pour-Point Depressants (PPDs) are often added to diesel to remediate issues with fluidity in cold climates. In this study, a series of benzyl methacrylate-methacrylate copolymers (MB-R1MC, R1 = C12, C14, C16, C18) and benzyl methacrylate-tetradecyl methacrylate (MB-C14MC) in different molar ratios of the functional monomers (1:1, 1:5, 1:10, 1:15, and 1:20) was synthesized by radical polymerization and characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). The depression effects of these PPDs in diesel were investigated and compared with previous reports. Results showed that diesel treated with 3000 ppm MB-C14MC (1:10) exhibited the best depression on solid Point and cold filter-plugging Point (CFPP) by 26 and 12 °C, respectively, and the CFPP depression was evidently superior to that in a previous research. Moreover, the action mechanism was explored by differential scanning calorimeter, polarizing optical microscopy and rheology analysis. Results showed that the nonpolar component of PPDs co-crystallized with n-alkanes and provided large number of crystallization sites in diesel, whereas the polar components adsorbed on the wax crystal surface, thereby changing the shape, decreasing the size, and increasing the dispersity of wax crystal. Therefore, MB-C14MC copolymer was confirmed to be an excellent PPD of diesel fuel.

  • influence of poly methacrylate co maleic anhydride Pour Point Depressant with various pendants on low temperature flowability of diesel fuel
    Fuel, 2018
    Co-Authors: Yuan Xue, Zhicheng Zhao, Xiang Lian, Hualin Lin, Sheng Han
    Abstract:

    Abstract To investigate the influence of various pendants in comb-type copolymers on the low-temperature flowability of diesel fuel, a series of methacrylate-co-maleic anhydride copolymers R1MC-MA (R1 = C14, C16, C18) were synthesized. And C14MC-MA was aminated by R2NH2 (R2 = C14, C16, C18, phenyl, 1-naphthyl) to obtain a series of aminated copolymers C14MC-MA-a (C14MC-MA-14a, C14MC-MA-16a, C14MC-MA-18a, C14MC-MA-phenylamine, C14MC-MA-naphthylamine). They were characterized by Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC). The influence of these Pour Point Depressants (PPDs) on the cold flow properties of diesel fuel were investigated. The crystallization behavior and crystal morphology of diesel fuel were also studied by differential scanning calorimeter (DSC) and polarizing optical microscope (POM). When the dosage of PPDs was 1000 ppm, C14MC-MA-14a displayed an excellent depression on cold filter plugging Point (CFPP) by 5 °C, C14MC-MA-phenylamine showed the best depression on solid Point (SP) by 17 °C, and PPDC-1 (the mixture of C14MC-MA-14a with C14MC-MA-phenylamine) exhibited the best performance in depressing the CFPP and SP by 8 °C and 18 °C respectively. The results show that the effects of the PPDs on reducing SP and CFPP sometimes are inconsistent, because SP is closely related to the crystal/liquid interface, while CFPP is directly related to the wax crystal size. When Pour Point Depressants are added, the wax crystals become smaller and regular (act as wax dispersants), thus inhibiting the formation of the porous network. So the CFPP decreased with decreasing the wax crystal size; and the SP first decreased with decreasing the wax crystal size, while when the wax crystals are too small, the large specific surface energy leads to the recovery of the SP. DSC and POM results showed that PPDs changed the crystallization behavior, size and shape of wax crystals, weakened the ability of wax crystals to form a three-dimensional network structure and made the wax crystals more uniform, compact, and dense. Therefore, the low temperature flowability of diesel fuel is improved by the synthesized Pour Point Depressant.

  • A new kind of nanohybrid poly(tetradecyl methyl-acrylate)-graphene oxide as Pour Point Depressant to evaluate the cold flow properties and exhaust gas emissions of diesel fuels
    Fuel, 2018
    Co-Authors: Zhicheng Zhao, Yuan Xue, Yan Song, Lian Jun, Chang Wei, Sheng Han
    Abstract:

    Abstract In this paper, a new kind of nanohybrid poly(tetradecyl methyl-acrylate)-graphene oxide (PMA14-GO) as Pour Point Depressant (PPD) was prepared from graphene oxide, using matrix via in situ free radical polymerization. The effect of PMA14-GO (i.e., PMA14-3GO, PMA14-6GO and PMA14-9GO) PPDs on the cold flow properties and exhaust gas emissions of diesel fuels were studied. Results indicated that PMA14-GO PPDs exhibited a better effect on cold filter plugging Point (CFPP) and solidifying Point (SP) than that of PMA14. Among them, PMA14-6GO and PMA14-9GO were the most suitable candidates for improving CFPP and SP. Specifically, upon addition of 0.2 wt% PMA14-6GO could reduce the CFPP of diesel by 14 °C, and 0.2 wt% PMA14-9GO reduced the SP of diesel by 19 °C. Moreover, PMA14-GO PPDs could effectively lower the low-temperature. Other fuel properties were also determined and compared with the ASTM D975 . Given the heterogeneous nucleation mechanism, uniform and tiny particle-shaped crystals were observed by polarizing optical microscopy and differential scanning calorimetry. In addition, burning diesel fuel with PMA14-GO PPDs effectively reduced HC and CO emissions, whereas NO and CO2 emissions increased with the increased engine speed at full load.

  • Effect of poly-alpha-olefin Pour Point Depressant on cold flow properties of waste cooking oil biodiesel blends
    Fuel, 2016
    Co-Authors: Yuan Xue, Weina Zhao, Zhicheng Zhao, Xiang Lian, Hualin Lin, Chao Yang, Xu Guangwen, Ma Peng, Sheng Han
    Abstract:

    Abstract Improving the flow ability at a low temperature is vital for the utilization and popularization of biodiesel. The cold flow properties of waste cooking oil biodiesel–0# diesel blends with poly-alpha-olefin (PAO) Pour Point Depressants were studied. Here results showed that B20 (20 vol.% biodiesel-80 vol.% diesel) treated with 400 ppm PAO exhibited the best depression in cloud Point, cold filter plugging Point and Pour Point by 8 °C, 9 °C and 7 °C, respectively. The other fuel properties of B20 were also determined and compared with the limits indicated in the ASTM D7467 standard. Viscosity–temperature curves, polarized optical microscopy, low-temperature X-ray diffraction, and differential scanning calorimetry were used to explore the performance mechanism of PAO in biodiesel blends; and results presented that PAO could effectively lower the low-temperature viscosity, delay the aggregation of wax crystals and modify their crystallization behavior by transforming the shape of crystals and depressing the formation of large wax crystals.