Synthesis and characterization of N-alkyl-2-aminopyridinum oligomers as pour point depressants for crude oil

The synthesis of N-decyl- (C10P), N-dodecyl- (C12P) and N-cetyl-2-aminopyridinum (C16P) oligomers was achieved by oxidative polymerization of N-decyl- (C₁₀), N-dodecyl- (C₁₂) and N-cetyl-2-aminopyridinium bromide monomers respectively in aqueous acid medium. Density function theory (DFT) was applied to recognize the reactive center in monomers used. The result of quantum calculations indicated that the oligomerization could proceed via open ring reaction. The obtained oligomers were characterized using FTIR and ¹H NMR spectroscopy. In addition, the XRD and SEM were used to investigate the morphology of the prepared oligomers. The thermal stability of the obtained oligomers was followed by thermogravimetric analysis (TGA). The conversion of these oligomers is ranged from 61 to 68% and the weight average molecular weights are closed to 3000?g?mol^?1. The surface tension of the synthesized oligomers was measured at different concentrations and temperatures. The efficiency of the synthesized oligomers in depressing the pour point of crude oil was investigated. The synthesized oligomers showed high efficiency as pour point dispersants.     

新型胺解原油降凝剂PSMA的合成与性能评价

采用分散聚合法以聚乙烯吡咯烷酮(PVP)为分散剂,无水乙醇为分散介质,合成了马来酸酐和甲基丙烯酸十八酯为单体的二元共聚物(PSMA-a),并对聚合物用苯胺进行酰胺化处理,得到降凝剂PSMA。采用傅里叶红外光谱和热失重对聚合物的结构和热稳定性进行表征。以大庆油田原油为实验对象,采用差示扫描热分析、石油凝点试验仪和石油产品运动黏度计对其进行了降凝降黏性能的研究。通过正交试验确定了最佳的单体配比、反应温度、反应时间和引发剂用量。实验表明,当降凝剂质量浓度为750mg/L,PVP用量为单体总质量分数的8%时,具有最佳的降凝降黏效果。     

Preparation and evaluation of some eco-friendly olethio-amide derivatives as lube oil additives

Eco-friendly synthesis of organic compounds is a major trend in green chemistry. Thus, we aim at producing some of the lube oil additives through the use of green chemistry. Dispersant lube oil additives are remarkable additives that regulate the formation of deposits throughout the process. Antioxidants do not prevent the oxidation reactions but only delay the rate of this process. In the present work, some additives for lube oil based on thiourea derivative were prepared by one-step reaction, which is the reaction of octadeca-7-enoy) chloride with ammonium thiocyanate in addition to different amines such as ethylenediamine, diethylene triamine, and tetraethylene pentamine as three-component system in order to prepare thioamide derivatives (A, B, and C). Infrared spectroscopy, elemental analysis, nuclear magnetic resonance, determination of molecular weights, and yield determination verified the chemical structure of all synthesized molecules. All the compounds produced are tested as lube oil additives (dispersants and antioxidants), and it has been found that all the compounds prepared are good as dispersants but have poor effect as antioxidants. The theoretical result is the same as the experimental result of antioxidants through the use of the quantum chemical calculations by calculating the energy gap (EHOMO-ELUMO). The best dispersant lube oil additive is (C).     

Synthesis of comb bipolymers and their pour point depressing properties

A bipolymer maleic anhydride-methyl acrylate(MAMA) was synthesized from maleic anhydride and methyl acrylate based on molecular design. MAMA further reacted with oleylamine or octadecyl alcohol to generate two comb polymers called Oleamide-MAMA(NMAMA) and OctadecanolMAMA(OMAMA), respectively. The structure of both the polymers was confirmed by their infrared spectral analysis(IR), gel permeation chromatography analysis(GPC) and differential scanning calorimeter(DSC). Moreover, the pour point depressing(PPD) properties of these comb polymers were examined experimentally. Experimental results showed that besides the molecular weight and concentration of the polymers, the length of side chains and the number of functional groups also had great influence on the pour point depressing performance. The π bonds and hydrogen bonds between depressants were the key factors for improving the pour point depressing properties. These results suggest that both OMAMA and NMAMA are potential pour point depressants for industry.     

树枝状长链酯的合成及其作为原油流动改性剂性能研究

以低代树状聚酰胺-胺和系列丙烯酸长链酯为原料,通过分子设计合成了6种具有树状结构的原油流动改性剂。采用傅里叶红外光谱、核磁共振氢谱和元素分析对其结构进行了表征,并研究了系列树枝状长链酯对原油流动性能的影响,主要分析了树状长链酯对原油凝点和流变性能的影响。结果表明,树枝状长链酯对原油流动性的影响不仅与其端基烷基链长度有关,而且与其代数也有关。端基烷基链越长,添加树状长链酯原油体系的凝点和表观粘度降低的越明显;含有8 个支化长链的1.5代树状长链酯对降低原油凝点和表观粘度的效率高于含有4个支化长链的0.5代树枝状长链酯。相同条件下,添加1.5代树状十八酯原油体系的原油凝点和表观粘度高于添加其它1.5代树枝状长链酯的原油体系。     

Synthesis and performance evaluation of vegetable oil polymer as a multifunctional lube oil additive

Abstract

The development and utilization of vegetable oils for polymeric materials are currently in the spotlight of the polymer and chemical industry. In this work homopolymer of palm oil and copolymer of it’s with decyl acrylate was prepared and their characterisation was carried out by spectral method, thermogravimitric analysis and gel permeation chromatography method. Performance of these polymers was evaluated by standard ASTM method in base oil. Biodegradability test of polymers was also carried out and shows excellent positive results. A comparison of their performances has also been evaluated and reported.     

Influence of alkyl methacrylate-maleic anhydride-1-hexadecene terpolymers and their mixtures with ethylene-vinyl acetate as pour point depressants in diesel fuel

In this paper, tetradecyl methacrylate-maleic anhydride-1-hexadecene (C₁₄MC-MA-HE) terpolymers in various molar ratios was prepared and used as pour point depressants (PPDs) in 0^# diesel fuel. Results showed that C₁₄MC-MA-HE terpolymers exerted distinct depression effects on solid point (SP) and cold filter plugging point (CFPP) at 0.15?wt.%, especially in 4:1:1 and 4:4:1 ratio. To obtain better PPDs, the terpolymers were mixed with ethylene-vinyl acetate copolymer (EVA) at 1:1 mass ratio, and have proved to present better synergistic effects. PPDC-2 exhibited the best depression in both CFPP and SP by 20?°C at 0.15?wt.%. Additionally, the performance mechanism was explored.     

降凝剂对JZ20-2油气田海底管输高凝点混合原油流变性影响的试验研究

JZ20-2油气田产出原油类型复杂,主要为低凝油、黑油和凝析油.利用试验手段,研究了降凝剂对JZ20-2油气田混合原油流变性的影响.通过降凝剂评价试验对降凝剂剂型、处理温度和加剂量进行了优选;通过管输模拟试验对加降凝剂处理后混输原油的降凝效果和稳定性进行了评价.该项研究及其结果对加降凝剂原油输送技术在我国海上的进一步应用有一定借鉴意义.     

高凝原油降凝剂的合成及复配性能研究

根据高凝原油组成以及降凝剂对原油的感受性确定了合成降凝剂的高碳醇的碳数,以丙烯酸和C18～C22混合醇为原料,合成丙烯酸高碳醇酯,得到三种聚合物:丙烯酸酯自聚物(AM),丙烯酸酯-醋酸乙烯酯(AMV)和丙烯酸酯-醋酸乙烯酯-苯乙烯(AVS)。比较了三种聚合物的降凝效果,选出AVS考察其合成条件并且与常用降凝剂EVA进行复配。实验结果表明:丙烯酸酯、醋酸乙烯酯、苯乙烯最佳配比为1∶1∶0.5,引发剂用量为1.2%,单体质量浓度30%,反应时间为7h时,三元共聚物AVS与EVA的复配物CPR可以使魏岗原油凝固点降低10℃,防蜡率达到40.62%。     

Synthesis of phthalimide and succinimide copolymers and their evaluation as flow improvers for an Egyptian waxy crude oil

This paper describes the synthesis, characterization and performance evaluation of three phthalimide and three succinimide copolymers of vinyl acetate, styrene and methyl methacrylate as flow improvers for waxy crude oil. The prepared copolymers were named as; (VA)Ph; (St)Ph; (MMA)Ph; (VA)S; (St)S and (MMA)S. These copolymers were characterized by FTIR and ¹H NMR spectroscopy. The molecular weights and nitrogen content of these copolymers were determined by using the GPC technique and the Kjeldhal method, respectively. The rheological properties of crude oil (with and without additives) were studied. From the obtained results, it was remarked that the styrene phthalimide copolymer (St)Ph exhibited the maximum pour point depression (ΔPP_500 ppm = 30). The results of the rheological flow properties showed that the Bingham yield values (τ_β) for crude oil without additives at 15, 27 and 39 °C were 0.286, 0.131 and 0.075 Pa respectively, whereas the τ_β for the treated crude oil by the styrene phthalimide (St)Ph copolymer were 0.021, 0.0164 and 0.0081 Pa at 500 ppm at the same temperatures.     

The effects of additives on the reduction of the pour point of diesel fuel and fuel oil

One important industrial problem is the wax precipitation of oil fractions. Factors such as oil composition, temperature, and pressure are effective in causing wax precipitation. One way to prevent wax precipitation is using of chemical inhibitors to reduce pour point. Studying the effects of additives on specific oil samples could help solve wax precipitation problems at various oil processing stages. Despite previous studies that have been done at this aim, finding materials that could decrease the pour point and be economically acceptable, environmentally well optimized, and reasonable is still an unsolved problem. So, it is important to make use of effective materials that could be influential in preventing of wax precipitation or reduction of the amount of precipitation and thus decrease the pour point temperature. In this study, the effects of industrial polymer additives and surfactants that are economically acceptable on decrement of pour point temperature were studied by using three oil product samples, namely light diesel, heavy diesel, and fuel oil (Purification Company of Esfahan). Furthermore, optimized type and concentration of the additives were studied. Results showed that copolymer ethylene-vinyl acetate 28% at a concentration of 500 ppm reduced pour point temperature by 12°C for diesel and that copolymer ethylene-vinyl acetate 19% at a concentration of 300 ppm reduced pour point temperature by 9°C for fuel oil.     

Synthesis of cyclohexanone-alcohol hemiketals and evaluation as flow improver for waxy crude oil

In this paper, four novel cyclohexanone-alcohol hemiketals (KL-1, KL-2, KL-3, KL-4) as waxy crude oil flow improver have been prepared by cyclohexanone and 1-pentanol, 1-Hexanol, 1-heptanol, 1-octanol. Evaluation results demonstrate the hemiketal compounds have obvious effect on the viscosity and pour point of Henan crude oil. DSC analysis showed that waxing point and waxing peak decreased to a certain degree in 0.05% hemiketal solutions. Wax crystal morphology analysis indicated the four hemiketals played a role of nucleation in the process of waxy crude oil decoagulation, and in that way acts as waxy crude oil flow improver.     

Development and growth of science-intensive production of lube oil additives in the transition to a market economy

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, pp. 2–4, May, 1991.     

潍北高凝点原油降凝降黏剂的研制

实验室自制的三元共聚物AMV-22与EVA复配,添加SLA-107作助剂,制备适用于胜利油田潍北区块高凝点原油的降凝剂AMVES。实验考察了该降凝剂对原油的降凝降黏效果。DSC热分析结果表明,AMVES加量为1000 mg/L时,可使原油凝点从48℃降低到37℃,析蜡点降低2℃。流变性曲线表明原油的剪切稀释作用随温度升高显著增强,当剪切速率大于100 s^-1后黏度基本不变,降凝剂可以大幅降低启动原油的屈服应力。偏光显微镜图显示原油温度越低,蜡晶网状结构越致密,交联度强,黏度大,流动性差;加AMVES之后原油中蜡晶变为团簇状颗粒,原油的流动性增强。由此可见降凝剂AMVES作用于蜡晶使其三维网状结构破坏,从而有效降低原油凝点和黏度。     

Effect of chemical structure on the cloud point of some new non-ionic surfactants based on bisphenol in relation to their surface active properties

A series of non-ionic surfactants were prepared from bisphenol derived from acetone (A), acetophenone (AC) and cyclohexanone (CH). The prepared bisphenols were ethoxylated at different degrees of ethylene oxide (27, 35, 43). The ethoxylated bisphenols were non-esterified by fatty acids; decanoic, lauric, myristic, palmitic, stearic, oleic, linoloic and linolinic. Some surface active properties for these surfactants were measured and calculated such as, surface tension [γ], critical micelle concentration [CMC], minimum area per molecule [A_min], surface excess [C_max], free energy of micellization and adsorption [ΔG_mic] and [ΔG_ads]. At a certain temperature, the cloud point was measured for these surfactants. From the obtained data it was found that; the cloud point is very sensitive to the increase of the alkyl chain length, content of ethylene oxide and degree of unsaturation. The core of bisphenol affected the cloud point sharply and they are ranked regarding bisphenol structure as BA > BCH > BAC. By inspection of the surface active properties of these surfactants, a good relation was obtained with their cloud points. The data were discussed on the light of their chemical structures.