含氮原油降凝剂的合成及评价

以马来酸酐(MA)和丙烯酸十八酯(OA)为单体进行聚合,并用十二胺接枝改性,合成了丙烯酸十八酯-马来酸双十二烷基酰胺梳型共聚物(POMN)。用红外光谱对聚合物进行了表征,并考察了该降凝剂对长庆含蜡原油的降凝减黏效果。结果表明,当n(MA):n(OA)=1:4,加剂量为300μg/g,加剂温度为60℃时,降凝效果较好,原油凝点降低13℃,原油低温黏度也大大降低。为了进一步扩大降凝效果,进行了复配实验。结果表明,POMN与乙烯-醋酸乙烯酯(EVA)按质量比为1:1复配,效果最佳,降凝幅度可达17℃,大大改善了含蜡原油的低温流动性能。     

The interaction of waxes with pour point depressants

Paraffin wax deposition from crude oils at low temperature is one of the serious and long-standing problems in petroleum industry. Addition of pour point depressants (PPD) has been proved to be an efficient way to inhibit wax deposition. The influence of PPD on wax precipitation at low temperature was investigated. The amount and composition of wax precipitated from paraffin solutions with and without PPD at different temperatures were studied by high speed centrifuge and gas chromatography (GC), respectively. The interactions between waxes and PPD were investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results showed that PPD do not completely prevent the wax from precipitating, but just shift the precipitation toward a lower temperature. This conclusion was identified from the analysis of the amount and composition of precipitated wax as well as the transition temperatures and energies of wax. It was shown that this effect is due to the structure of wax is partly transformed from orthorhombic into hexagonal form by PPD.     

共聚物ME-TA-MA的合成及对盘锦原油的降凝降粘作用

根据盘锦原油的性质,成功研制了以甲基丙烯酸、十四醇、马来酸酐为原料的共聚物ME-TA-MA降凝降粘剂。单因素实验确定了合适的工艺条件。酯化：n（十四醇）∶n（甲基丙烯酸）=1.25∶1,m（催化剂）：m（甲基丙烯酸＋十四醇）=2%,m（溶剂）∶m（甲基丙烯酸＋十四醇）=50%;聚合：n（马来酸酐）∶n（酯化产物）=1∶1,m（引发剂）：（甲基丙烯酸十四酯＋马来酸酐）=1.5%,m（溶剂）∶m（甲基丙烯酸十四酯＋马来酸酐）=50%,聚合温度80℃,聚合时间3h。IR结果表明,所制备产物的官能团结构与设计的目标产物相符。将最佳条件下合成的产物以m（降凝剂）∶m（原油）=0.23%的加剂量加入到盘锦原油中,凝点可降低13℃,粘度可降低61.33%。     

一种润滑油降凝剂的合成与应用

介绍了一种润滑油基础油降凝剂的合成及其用于150 SN润滑基础油的降凝效果。该降凝剂以马来酸酐、十八胺、乙酸乙烯酯为原料,以二甲苯为溶剂,对甲苯磺酸作为催化剂,通过胺化和聚合反应制得。通过红外表征,表明所合成的产物与设计的分子结构吻合。考察了反应的工艺条件对降凝剂降凝效果的影响。该降凝剂对大庆润滑油厂的150SN润滑油基础油有一定的效果。     

Ozonized vegetable oil as pour point depressant for neat biodiesel

The use of ozonized vegetable oils as pour point depressant for neat biodiesel was evaluated. Ozonized vegetable oils (1-1.5% by weight) were effective in reducing the pour point of biodiesel prepared from sunflower oil, soybean oil and rapeseed oil to −24, −12 and −30 °C, respectively. Cloud point however remained unaffected. In the case of palm oil biodiesel, significant reduction was observed in cloud point but not in pour point. Statistical analyses showed that neat biodiesel and biodiesel treated with ozonized vegetable oils showed no significant difference in other properties including density and viscosity. Although ozonized vegetable oils increase the flash point of biodiesel, the values are still within the limits set by the standards in the US and Europe. Lowest reduction in pour point was observed in cases where the biodiesel and the ozonized samples were prepared from the same vegetable oil. Hence, a correlation may exist between the nature of the biodiesel and ozonized oil. Microscopic analysis at low temperature revealed that ozonized vegetable oil impede agglomeration of biodiesel into network of solidified material giving crystals with sizes around 10 μm.     

Effect of wax inhibitors on pour point and rheological properties of Iranian waxy crude oil

A variety of techniques have been employed in order to reduce problems caused by the crystallization of paraffin during the production and/or transportation of waxy crude oil. Flow improvers are used extensively to increase the mobility of crude oil. In this study, the influence of the ethylene-vinyl acetate copolymer (EVA), as flow improver, with different ranges of molecular weight on the viscosity and pour point of five Iranian waxy crude oils was evaluated. Five types of Iranian waxy crude oil were selected based on their similar wax (> 10%) but different asphaltene contents. Also, the effect of asphaltene content on the performance of this flow improver was studied. The rheological behavior of these crude oils, with middle range API gravity, in the absence/presence of flow improver was studied. The rheological data cover the temperature range of 5 to 40 °C. The results indicated that the performance of flow improver was dependent on the molecular weight and the asphaltene content. For crude oil with low asphaltene, higher molecular weight flow improvers are the best additive and lower molecular weight flow improvers showed good efficiency for crude oil with high asphaltene content. Addition of small quantities of asphaltene solvents such as xylene (1 wt.%), alone or in combination with flow improver, can improve viscosity of crude oil with high asphaltene content.     

原油降凝剂及其在我国原油中的应用

介绍了原油降凝剂在国内外的发展概况和种类、降凝作用机理、对降凝剂效果的影响因素,以及我国降凝剂的研究情况.     

DFT and MM calculation: the performance mechanism of pour point depressants study

Adding pour point depressants (PPDs) to lower the cold filter plugging point (CFPP) of oils has been widely used as the most valuable way in the world. To develop the new type of PPDs according to the oils of different kinds, many researchers have tried to study the performance mechanism of PPDs with different methods. In this article, we have carried out this study with density function theory and molecular mechanics calculation methods. From the results of different systems, we have found that: (1) Alkane molecule is non-polar but the methyl groups on the chain ends have higher electronegativity than all the methylene groups. (2) The EVA (copolymer of ethylene and vinyl acetate) molecule is divided into segments by the polar groups, and the segments are composed of carbon chains, while at the joint points of the segments are ester groups. Calculation results show that the non-polar parts of EVA molecule have good affinity to the adjacent alkane molecules. The rigidity of the carbon bonds neighboring to ester groups is enhanced by the introduction of ester groups, which can also help the next segments to get into the next crystal units and accelerate the growth rate of the planes perpendicular to (001) plane. (3) The alkane molecules absorbed on the PPD molecules can be bent, and the bending conformation brings steric hindrance effect to the molecules to deposit on the surface near the PPD molecules. The relatively higher electronegativity of the methyl groups, which are bent out of the crystal units, can also bring more repulsion effect to the alkane molecules to deposit. This helps to restrict the high growing velocity of (001) plane and results in the uniformity growing rate in three dimensions. (4) If we want to get the good performance properties of PPDs, the carbon number should be a little lower than the mean carbon number of the wax crystals. Then the acetate percent of EVA molecules should be around 30% and the concrete value should be determined according to the oils used.     

原油降凝剂中间体的合成及处理

报道了原油降凝剂中间体的合成及如何清除中间体中阻聚剂的新方法。     

PMMVA润滑油降凝剂的合成及其降凝效果

用混合高碳醇、十八胺分别与马来酸酐反应得到醇解产物和胺解产物,再以2种产物以及醋酸乙烯酯为单体,三元共聚得到目标产物：马来酸混合醇酯-马来酸十八酰胺-醋酸乙烯酯共聚物（PM—MVA）。正交实验确定了缩合反应中醇解反应的最优工艺条件：n（马来酸酐）：n（混合醇）-1：1、m（催化剂）：m（反应物）-2．0％、m（溶剂）：m（反应物）-40％。胺解反应以反应物n（马来酸酐）：n（十八胺）=1：2进行。正交实验确定最佳的聚合工艺条件：n（缩合产物）：n（醋酸乙烯酯）-1：1．5、m（引发刑）：m（聚合单体）-1．5％、m（溶剂）：m（聚合单体）-30％、聚合温度75℃、聚合时间4h。IR结果表明：所制备产物的官能团结构与设计的目标产物相符。将最佳条件下合成的产物以硼（降凝剂润滑油）-0．85％加入到150SN润滑油基础油中,凝点可降低17℃。     

集输工艺对高蜡原油中降凝剂作用的影响分析

高蜡原油的集输工艺对降凝剂的降凝降黏作用有较大影响。使用降凝剂AE对吉林木南原油降凝处理,考察了集输过程中降凝剂加量和加剂温度、泵的高速剪切、原油的重复加热和输送过程中冷却速率等工艺条件对降凝剂作用效果的影响。结果表明,降凝剂最佳加剂量0.7%,最佳加剂温度70℃,高速剪切温度应在析蜡点10℃以上,重复加热温度应不低于60℃,在55～40℃的析蜡高峰区应使原油温度缓慢降低。     

Synthesis and characterization of nanohybrid of poly(octadecylacrylates derivatives)/montmorillonite as pour point depressants and flow improver for waxy crude oil

In this paper, a novel series of nanohybrid of poly(octadecylacrylate derivatives) montmorillonite (ODA/MMT) was prepared by successfully dispersing the inorganic nanolayers of MMT-clay on the organic polymer matrix via in situ free-radical polymerization by different ratios. The prepared nanohybrid polymers were characterized by FTIR and Raman spectroscopy, X-ray diffraction (XRD), HRTEM, GPC, DSC, and TGA instruments. The XRD confirmed the presence of an exfoliated/interacted clay structure in the prepared polymer. Moreover, the molecular weight of the prepared polymer nanohybrids is higher than the corresponding polymer. The results of applying the polymer as pour point depressants showed a considerable reduction from 27°C (initial pour point) to −3 °C, facilitating the process of oil flow at lower temperatures than earlier. The apparent viscosity of waxy crude oil was also decreased significantly by the addition of the (ODA/MMT) polymers, and the long-term stability of the prepared nanohybrid polymers was superior to that of a conventional polymer. The efficiency of polymers nanohybrid in reducing the pour point of crude oil associated with improved oil flow is one of the most important processes of charge and transportation process. The mechanism of enhancement of the flow properties by the polymers nanohybrid is predicted. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47333.     

Synthesis of methacrylate copolymers and their effects as pour point depressants for lubricant oil

In this study, polymethacrylate polymers were synthesized by free‐radical polymerization for use as pour point depressants in lubricant oil, and their low‐temperature properties were investigated. Four methacrylate monomers were synthesized by the esterification of methyl methacrylate (MMA) with four kinds of fatty alcohols. The purification step was performed to prepare the pure monomers. Two polymerization experiments were carried out with four kinds of methacrylate monomers obtained previously and MMA. Copolymers, which were made from one kind of monomer and MMA, and terpolymers, which were made from two kinds of monomers and MMA, were prepared. The molecular structures of the synthesized methacrylate monomers and polymethacrylate polymers were verified by ¹H‐NMR, and the molecular weight data were obtained by gel permeation chromatography. The pour points of the base oils containing 0.1 wt % polymethacrylate polymers were measured according to ASTM D 97‐93. The pour points of most base oils containing each polymer decreased compared to that of the pure base oil. Particularly, poly(dodecyl methacrylate‐co‐hexadecyl methacrylate‐co‐methyl methacrylate), made of dodecyl methacrylate, hexadecyl methacrylate, and MMA at a molar ratio of 3.5 : 3.5 : 3, showed the best low‐temperature properties. This terpolymer dropped the pour point of the base oil by as much as 23°C, and its yield was 93.5%. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

降凝降黏剂在原油开采集输中的应用

降凝降黏剂已成为钻高难度的高温深井、大斜度定向井、水平井和各种复杂地层的重要手段,并且还可广泛地用作解卡液、射孔完井液、修井液和取心液等。由于稠油的黏度以及凝点低,防止在开采过程中出现困难,降凝降黏剂的应用需要进行一定的关注,解决其发展困难。     

高含蜡原油聚烯烃降凝防蜡剂合成及性能评价

为了保障海上原油长距离管输低温流动安全,以丙烯酸十八酯、十八烯和苯乙烯为单体合成三元共聚物,以其为主剂合成聚烯烃降凝防蜡剂POOS,对三元共聚物的合成条件进行了优化,并对加剂前后原油流变性、析蜡特性、微观形态以及降凝防蜡效果进行评价。结果表明,共聚物优化合成工艺条件为：单体摩尔配比n(丙烯酸十八酯):n(十八烯):n(苯乙烯)=5:3:2,引发剂过氧化苯甲酰质量分数5 ‰,反应温度70 ℃,反应时间8 h。当POOS质量浓度为200 mg/L时,原油流变性与未加POOS原油相比变化明显,15 ℃下加剂前后屈服应力为50.3和2.95 Pa,屈服应力降幅94 %,析蜡温度由31.33 ℃降至24.94 ℃,凝点由25 ℃降至15 ℃,冷指测试防蜡率88 %,环道测试防蜡率83.7 %,微观分析蜡晶形态由针状转变为圆状结晶,析出分布不均匀,多个微小蜡晶聚集析出形成单个聚集体,加剂有效改善蜡晶分散形态,抑制网状结构形成,显著改善原油低温流动效果。     

新型原油降凝剂的绿色合成与复配研究

将一种电荷转移配合物（CTC）与丙烯酸十八酯（SA）发生聚合反应,合成出一种性能优良的降凝剂（CS）,在加量为900μg/g时,可使长庆原油的凝点下降10℃;CS与T-1804A复配比例为1∶1时,可使长庆原油凝点下降14℃。通过差示扫描量热,研究了降凝机理及复配机理。结果表明,降凝剂的加入使得系统的热能发生改变,增加了相变能。     

Polymeric additives for pour point depression of residual fuel oils

Esters of styrene-maleic anhydride copolymers were synthesised by reacting styrene with maleic anhydride and esterifying the product with fatty alcohols. The resulting copolymers were purified and tested as pour point depressants for residual fuel oils. Comparative evaluation of these esters of styrene-maleic anhydride copolymers with some commercial additives showed their good activity.     

润滑油降凝剂T818C的合成及其降凝作用

本文研究了润滑油降凝剂T818C（醋酸乙烯-富马酸酯高聚物）的合成,考察了该降凝剂对国内几种主要基础油的降凝效果,并探讨了其降凝机理。结果表明当加剂量为3g／kg～5g／kg时,T818C降凝剂对环烷基基础油和石蜡基基础油均具有很好的降凝作用。     

AE-MA型原油降凝剂的制备及效果评价

以甲基丙烯酸、混合醇、马来酸酐为原料,采用"先酯化-后聚合"的方法,合成一种新型原油降凝剂甲基丙烯酸混合醇酯-马来酸酐共聚物(AE-MA)。实验表明,最佳酯化条件为:n(甲基丙烯酸)∶n(混合醇)=1∶1.25、n(十二醇)∶n(十四醇)∶n(十六醇)=3∶6∶1,w(溶剂)=100%,w(催化剂)=1.5%;最佳聚合反应工艺条件为:n(马来酸酐)∶n(甲基丙烯酸混合醇酯)=1∶1,w(引发剂)=0.75%,聚合时间3.5 h,聚合温度80℃。将最佳条件下合成的产物按1.59%(质量分数)的剂量加入到盘锦原油中,原油凝点最多可降低11℃。     

Synthesis and characterization of novel pour point depressants based on maleic anhydride‐alkyl acrylates terpolymers

The (Docosanyl acrylate‐co‐(octadecyl or hexadecyl acrylate)‐co‐maleic anhydride) terpolymers were prepared using different compositions of the used alkyl acrylates (namely, 90 : 10, 70 : 30, 50 : 50, 30 : 70, and 10 : 90) (DCA‐ODA)/(MA) or (DCA‐HDA)/(MA). The efficiency of these terpolymers as pour point depressants was discussed. Two western desert waxy crude oils with different wax content were used for evaluation. Correlation between pour point depression efficiency and rheological properties were performed. Rheological parameters were also computed and discussed. It was observed that the synthesized terpolymers showed non‐Newtonian pseudoplastic relationships at different concentrations of synthesized terpolymeres with monomer feed ratios of (DCA‐ODA (1 : 1))/(MA) or (DCA‐HDA (1 : 1))/(MA) = 90/10 mole %. This ratio showed a good ability to disperse wax crystals and improve the flow behaviors of tested two crude oils even at low temperatures below their pour points. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010