Synthesis and Evaluation of Copolymers as Pour-point Depressants

Abstract

α-Olefin maleic anhydride copolymers were prepared by reacting C₈ or C₁₄ olefin with maleic anhydride, then esterified with dodecyl or NAFOL 1822B alcohol, purified and characterized through average molecular weight, polydispersity index, and infrared spectroscopy. A waxy crude oil (pour point = 21°C and wax content = 18.9 wt%) was treated with the four synthesized additives as pour-point depressants and determined using x-ray diffractometer. It is found that the x-ray diffraction patterns of waxes with additives are remarkably different from those without additives. The NAFOL 1822B ester of 1-tetradecene maleic anhydride copolymer also show stronger interaction with the wax than NAFOL 1822B ester of 1-octene copolymer, dodecyl ester of 1-tetradecene maleic anhydride copolymer, and dodecy ester of 1-octene maleic anhydride copolymer. These effects can be attributed to the chain length of side hydrocarbon. The wax solubilization is a function of copolymer.     

Effect of Flow Improvers on the Rheological Properties of Gas Oil and Gas Oil Raffinate

Abstract

The gas-oil feedstock was solvent extracted with pyrrolidone (NMP) at different temperatures (50°C–70°C) and at different solvent feed ratios (ranging from 2/1 to 5/1). The raffinates were treated with four flow improver additives—two synthesized improvers (poly NAFOL 1822C palmitate-Co-N,N ditallowamine phthalic diamide and poly NAFOL 1822C palmitate Co-N,N ethanolamine phthalic diamide) and two available commercial improvers 2437 (Com. 1) and commercial wax dispersant CWD-11 (Com. 2) to study their efficiencies and suitabilities for improving the rheological properties. The efficiency of the additives in reducing the pour point of gas oil and their raffinates is in the order: Sec. > Et. > Com. 1 > Com. 2.     

基于分子模拟的铁表面含酯燃油油膜吸附特性分析

将肉豆蔻酸甲酯(C₁₄)、棕榈酸甲酯(C₁₆)、硬脂酸甲酯(C₁₈)、油酸甲酯(C_18：1)、亚麻油酸甲酯(C_18：2)及蓖麻油酸甲酯(C _18：1OH)添加至柴油中,基于Materials Studio软件建立酯/正十四烷在铁表面吸附构型,分析含酯油膜的能量构成。结果表明：对于C₁₄酯/正十四烷混合物,随着酯体积分数增加,油膜的吸附能大幅增加,而内聚能总体差异较小;对于5%(体积分数)酯/正十四烷混合物,含不同酯油膜的吸附能总体上较为接近,但内聚能随着碳链长度、不饱和程度及极性基团等因素变化较大,其由大到小的顺序为C_18：1OH、C_18：2、C_18:1、C₁₈、C₁₆、C₁₄。对比酯体积分数与组分引起的油膜吸附能变化可见,酯体积分数是更重要的因子,但酯组分变化可引起内聚能显著的差异。酯体积分数增加和酯组分改变均为提升低硫柴油润滑性能的有效措施。     

Synthesis of polymeric additives based on itaconic acid and their evaluation as pour point depressants for lube oil in relation to rheological flow properties

Modification of the wax crystal habit practical interest during transportation processing of lube oil at low temperature. Various pour point depressant (PPD) additives can facilitate this modification by different mechanisms. Comb shaped polymer additives are known to depress the pour point of lube oil by providing different nucleation sites for the precipitation of wax. This paper describes performance based design, synthesis, characterization and evaluation of comb shaped polymeric additives. Alkyl itaconates were prepared by the esterification of itaconic acid with different saturated alcohols C₁₆/C₁₈/NAFOL 20+A (C_av = 20)/NAFOL 1822 B (C_av = 22). The four synthesized monomers were characterized and copolymerized with styrene in different molar ratios. All the products were characterized by infra-red (FTIR), Nuclear Magnetic Resonance (NMR) Spectroscopy and Gel permeation chromatography (GPC). Rheological properties of lube oil (with and without additives) were studied by Brookfield viscometer. In this study the additives based on itaconic acid were evaluated as good PPD and rheology modifiers.     

Evaluation of Effects of Selected Wax Inhibitors on Paraffin Deposition

Deposition from decane solutions of model paraffins such as n-C₂₄H₅₀ (C₂₄), and n-C₃₆H₇₄ (C₃₆), as well as a mixture of n-alkanes (C₂₁ to C₄₄) was examined with and without chemical wax deposition inhibitors. The device used to produce the deposits investigated was a “Cold Disk” Wax Deposition Apparatus (CoDWaD) capable of producing field like deposits with relatively small volumes of oil in minutes. It was found that most of commercial wax inhibitors tested could decrease the deposition of low molecular weight paraffins (C₃₄ and below), while having little effect on the wax deposition for high molecular weight paraffins (C₃₅-C₄₄). In many cases, although the total amount of wax formed on the cold plate was reduced, the absolute amount of deposition for high molecular wax was actually increased. Therefore, the net effect of many commercial inhibitors is to make even harder wax under the tests conditions studied here. One intriguing result was that the addition of an oleic imidazoline c rrosion inhibitor improved the performance of two wax inhibitors tested. It was also observed that there are subtle differences in inhibitor performance depending on whether the test solutions are binary mixtures, synthetic wax mixtures, or crude oil.     

Evaluation of Effects of Selected Wax Inhibitors on Wax Appearance and Disappearance Temperatures

In this investigation, a light transmittance method was used to evaluate the wax appearance temperatures (WAT) and wax disappearance temperatures (WDT) of model paraffin compounds (n-C₂₄H₅₀ (C₂₄) and n-C₃₆H₇₄ (C₃₆)) in n-decane (C₁₀) solutions both with and without wax inhibitors. The change in WAT at different paraffin concentrations in the presence of an inhibitor behaves as though there is a constant amount of paraffin removed by the inhibitor. However, the amount of apparent paraffin reduction by an inhibitor (e.g. 160 g of C₂₄ by one gram of an inhibitor) indicates that the inhibition mechanism cannot easily be explained by a simple “sequestering” effect. Wax inhibitors that decrease the WAT tend to also increase the WDT. Most of the wax inhibitors tested at a dosage of 100 ppm did suppress the WAT of lower molecular weight paraffin (C₂₄) solutions, but had little or no effect for higher molecular weight paraffin (C₃₆) solutions. Side-chain length of polymethacrylate wax inhibitors is an important performance parameter. Of the three polymethacrylate wax inhibitors tested, the one with the longest alkyl side-chain (C₁₈) had the most effect on suppressing the WAT and increasing the WDT of the binary mixtures (n-C₁₀-n-C₂₄ solutions).     

Studies on Carbon Number Distribution of High Melting Microcrystalline Waxes

Carbon number distribution of microcrystalline wax derived from tank sludges of Bombay High crude oil (India) and its various high melting fractions have been studied by High Temperature Gas Chromatography (HTGC). Binodal, Gaussian distribution and a wide range of alkanes, ranging from C₂₁-C₇₅, along with their many isomers with predominant alkanes being C₄₀ and C₆₇, have been observed in the microcrystalline wax. Higher melting wax fractions have Gaussian distribution.     

n-DIOCTADECYL FUMARATE-VINYL ACETATE COPOLYMER: SYNTHESIS, CHARACTERIZATION AND APPLICATION AS FLOW IMPROVER FOR OILS

Monomer n-dioctadecyl fumarate (DOF), and copolymers (C₁₈FVA) of DOF with vinyl acetate were synthesized. Monomer and copolymers were characterized by IR, ¹H-NMR, VPO and DSC. Due to the special structure of DOF, only copolymers containing 45.9%-97.8% (mol) DOF were obtained. The crystalline CH₂ numbers on polymer side chain χ were calculated from enthalpy determined by DSC, and it was found that χ slightly decreased with increasing vinyl acetate content. C₁₈FVA can be used as flow improver for viscous oil and residual oil, and the more the crystalline CH₂ number on the side chains, the better lattice match between copolymer and wax crystal structure of oils.     

硬脂酸二乙醇酰胺丙烯酸单酯-马来酸酐-醋酸乙烯酯共聚物柴油降凝剂制备及评价

以硬脂酸二乙醇酰胺丙烯酸单酯、马来酸酐、醋酸乙烯酯为单体,采用溶液聚合法合成了硬脂酸二乙醇酰胺丙烯酸单酯-马来酸酐-醋酸乙烯酯降凝剂,考察了单体物质的量比、引发剂用量、聚合温度对降凝效果的影响.通过红外光谱对共聚物分子结构进行了表征,结果表明,合成的分子结构和设计目标分子结构相符.此降凝剂可使东营0#柴油的凝点降低7℃...     

江汉原油降凝剂的制备及其性能研究

利用溶液聚合反应合成了一系列丙烯酸酯类高蜡原油降凝剂,并对其降凝效果进行研究。研究结果表明：采用摩尔配比为6：3：1的丙烯酸十八酯,马来酸酐和醋酸乙烯酯组成的混合单体制备的三元聚合物高蜡原油降凝剂MVA-3对江汉原油具有明显的降凝效果,在加剂量为1000mg／kg时,可以使江汉原油的凝点降低12℃。高蜡原油降凝剂MVA-3能够同原油中的胶质和沥青质有效结合,可以降低原油中固有的胶质一沥青质聚集体在原油中的析出温度,改变原油中蜡的结晶方式,降低蜡结晶析出温度和蜡结晶析出速度,并能减少原油中蜡的析出总量。     

大港原油高效降凝剂的研制

针对大港油田原油含蜡高的特点 ,以丙烯酸高碳醇酯 (HAA)、顺丁烯二酸酐 (MA)、苯乙烯 (ST)和醋酸乙烯酯 (VAc)为原料研制出适用的降凝剂 ,其中的HAA是用C1 8～C2 2 醇与丙烯酸 ,以对甲苯磺酸为催化剂 ,以对苯二酚为阻聚剂合成的 ,并采用自制的HJ 10 0无机试剂 (5 %NaNO3 水溶液 )回收了对苯二酚 ,回收率 99.2 %。将HAA/MA/ST/VAc按摩尔比 9∶1∶1∶1及 9∶1∶1∶0在 80℃ ,用过氧化苯甲酰引发 ,以N2 为保护气体 ,以甲苯为溶剂 ,回流 7h ,分别合成了四元共聚和三元共聚原油降凝剂A和B。当降凝剂A或B加入量为原油量的0 .2 %时 ,能使大港原油倾点下降 17℃和 9℃。     

渤海湾盆地黄骅坳陷滨海Ⅰ号构造原油的油源研究及意义

滨海Ⅰ号构造是渤海湾盆地黄骅坳陷歧口凹陷勘探程度很低的大型构造,所钻探的白东2×1井东营组发现低产油流。原油地球化学特征研究表明,该原油为中高蜡轻质成熟原油,甾烷组成中以胆甾烷和异胆甾烷为主,且C₂₇,C₂₈,C₂₉甾烷呈略不对称的"V"型分布,有一定量的重排甾烷和4-甲基甾烷;萜烷组成中三环萜烷略低于五环萜烷,伽马蜡烷高,Ts,C₂₉Ts和C₃₀重排藿烷含量相对较高。生物标志物分布特征表明该原油的生烃母质具有菌藻类和陆源高等植物混合特点,且沉积于半咸水—咸水环境,应该来源于歧口凹陷沙一下段或沙三段咸水湖相烃源岩。滨海Ⅰ号构造紧邻歧口生油凹陷,油气成藏条件好,具有良好的勘探前景。      

Synthesis and Evaluation of Some C14MC-MCNR2 Copolymers and C14MC-MA-MCNR2 Terpolymers as Cold Flow Improvers in the Diesel Fuels

In order to find efficient cold flow improvers for diesel fuels, a series of copolymers (C14MC-MCNR₂) derivated from long chain alkyl (i.e., tetradecyl) methacrylate C14MC and methacrylamide (MCNR₂) were prepared, and a series of terpolymers (C14MC-MA-MCNR₂) derivated from tetradecyl methacrylate C14MC, maleic anhydride (MA), and methacrylamide (MCNR₂) were also prepared. These copolymers and terpolymers were purified, and their structures were characterized by IR, ¹HNMR, and GPC. Their low temperature fluidities and filterability, such as solid point depression (ΔSP) and cold filter plugging point depression (ΔCFPP), used as cold flow improvers in two diesel fuels were evaluated. The results indicate that: (1) The C14MC-MCNR₂ copolymers possess good solid point depressing performance. (2) The C14MC-MA-MCNR₂ terpolymers exhibit dual function both as wax dispersants and flow improvers simultaneously, and they all possess very excellent solid point depressing performance, and can attain optimum effectiveness of CFPP depression when NR₂ is morpholine.     

A STUDY ON ALCOHOLS MIXTURE ESTERIFIED COPOLYMER OF MALEIC ANHYDRIDE WITH MIXED OLEFINS, ACRYLIC ALKYL ESTER AND STYRENE AS POUR-POINT DEPRESSANT FOR DIESELS

The Synthesis of mixed alcohols esterified copolymer of maleic anhydride with acrylic alkyl ester, olefins and styrene(MOAS) as pour-point depressant (PPD) for diesels was introduced. By using the synthesized MOAS, the pour-point (PP) and cold filter plugging point (CFPP) of the tested diesels made from Daqing crude oils were lowered obviously as those did by other PPDs. Meanwhile the machanism of its function was investigated.     

水热处理对HZSM-5分子筛乙苯乙烯烷基化反应性能的影响

针对在保持高选择性的前提下抑制催化剂的快速积炭失活问题,利用X射线衍射(XRD)、氨气程序升温脱附(NH₃-TPD)、N₂物理吸附-脱附(BET)和吡啶吸附傅里叶变换红外光谱(Py-FT-IR)等手段对水热处理后的HZSM-5催化剂进行表征,并详细考察了水热处理条件对反应性能的影响。结果表明,水热处理温度和时间对催化剂稳定性有显著影响,最佳水热处理条件为T=550 ℃、t=3 h、MHSV_H2↓O=1 h^-1。其中HT-550-3-1催化剂稳定性表现最好,反应32 h后乙苯转化率仅降低了2.6百分点,热重分析发现其炭质量损失率(1.38%)远低于HZSM-5的炭质量损失率(5.08%)。在最佳水热处理条件下的HZSM-5分子筛经过硅(Si)、镧(La)复合改性制得的HT-9%Si-4%La催化剂,在反应温度340~370 ℃、压力101.325 kPa、乙苯质量空速5 h^-1、n(C₈H₁₀)/n(C₂H₄)=5、n(N₂)/n(C₂H₄)=11.3的反应条件下,乙苯转化率高于12.1%,对二乙苯选择性超过97.0%,催化剂稳定运行454 h。     

润滑油降凝剂的合成与应用效果研究

合成了润滑油降凝剂苯乙烯马来酸酐C12～C16混合脂肪醇酯,实验室使用效果评价表明：对环烷基油的降凝效果优于商品降凝剂T803C和T808B。与T803B复配后,对石蜡基油也有较好的降凝效果。     

微波辐射梳形聚羧酸共聚物合成及其分散性能

以自制顺丁烯二酸聚乙二醇(n=9)单酯(MAPEG)、烯丙基磺酸钠(SAS)和顺丁烯二酸酐(MA)为单体,过硫酸铵为引发剂,在微波辐射下合成了梳形聚羧酸共聚物,并用傅里叶变换红外光谱对其结构进行了表征。考察了辐射功率和时间对梳形聚羧酸共聚物分子结构及分散性能的影响。实验结果表明,在微波辐射下,共聚反应所需时间很短,且梳形聚羧酸共聚物的分散性稳定。在n(SAS)∶n(MA)∶n(MAPEG)=3.6∶4.3∶1、引发剂用量1.0%(占总单体的质量)、辐射功率650W、辐射时间5min条件下,所得梳形聚羧酸共聚物的特性黏数为2.63×10-2dL/g;在水与水泥的质量比为0.35、梳形聚羧酸共聚物(n(SAS)∶n(MA)∶n(MAPEG)=3.6∶4.3∶1、引发剂用量1.0%、辐射功率260W和辐射时间5～10min或辐射功率130～650W和辐射时间6～10min)掺杂量(质量分数)为0.4%时,水泥净浆流动度稳定在230mm左右。     

裂解C5脱有机硫实验研究

针对炼油厂裂解C₅馏分脱除有机硫,对脱硫剂、最佳脱硫条件以及脱硫剂循环回收利用进行了研究。结果表明,质量分数5%复合胺溶液（TSC5）为最佳脱硫剂,在0.1 MPa、30℃、反应时间20 min和剂/油体积比0.3条件下,可使裂解C₅馏分的硫质量分数从106 μg/g降至8.7μg/g,脱硫率91.8%,收率99.4%。以洗涤水/油体积比1.5（其中循环再生水/油体积比1.3,去离子水/油体积比0.2）对脱硫后C₅馏分进行水洗,可将脱硫C₅馏分中的复合胺质量分数降至2 μg/g以下。在80℃、空速180 h^-1条件下,采用N₂汽提法对复合胺富液和洗涤水的混合液进行分离回收利用,其重新配制的TSC5脱硫剂的脱硫效果与新鲜剂相当。提出了裂解C₅深度脱有机硫的原则工艺流程。     

胺解聚合物型原油降凝剂的合成及应用

通过丙烯酸高碳酯与马来酸酐、醋酸乙烯酯、苯乙烯共聚后进行不同系列胺解得到一系列新型高蜡原油降凝剂。考察了该类降凝剂对大庆高蜡原油和尼尔阿曼混合原油的降凝效果。结果表明，胺解聚合物型原油降凝剂具有较好的原油降凝性能，降凝幅度最高达到27℃；同时，测定了加剂温度对降凝剂降凝效果的影响，结果发现，当加剂温度高于原油析蜡温度时，降凝剂的降凝效果才能充分显现出来。     

塔里木盆地塔河油田原油地球化学特征的化学计量学分析及应用

塔里木盆地塔河油田由于存在多期次原油充注导致其成因至今无法得到很好地解释。应用地球化学手段对塔河油田原油地球化学特征进行综合研究,结果显示：塔河油田奥陶系原油沉积于海相沉积环境,处于成熟—过成熟阶段,正构烷烃分布较完整、具有UCM鼓包、普遍存在25?降藿烷、伽马蜡烷含量低,C₂₉藿烷丰度高、规则甾烷呈现C₂₉>C₂₇>C₂₈分布、规则甾烷αββ构型丰度高于ααα构型等特征,表明塔河油田原油遭受过较强程度的微生物降解作用,存在至少2个期次的原油充注。利用主成分分析（PCA）和层序聚类分析（HCA）方法对原油生物标志化合物指标进行分析,将塔河油田原油分为3类：I类原油具有三环萜烷/五环萜烷、Ts/17αC₃₀藿烷、重排甾烷/规则甾烷、C₃₁/C₃₂藿烷、C₂₉/C₃₀藿烷、C₂₄/C₂₃三环萜烷、C₂₀₊₁₉/C₂₃₊₂₄三环萜烷、Ts/Tm高,Ph/nC₁₈低,正构烷烃分布完整,呈现出多期充注特征,但主要表现出早期生物降解原油的特征,早期生物降解原油的贡献高于后期充注正常原油的贡献;II类原油的nC₂₁^-/nC₂₂⁺值最低,部分样品正构烷烃缺失,UCM鼓包明显,主要代表早期经历过强烈微生物降解的原油; III类原油nC₂₁^-/nC₂₂⁺、αβC₃₁?22S/（22S+22R）、C₂₄四环/（C₂₄四环+C₂₆三环）值最高,正构烷烃受热成熟度的影响最大,高碳数正构烷烃大量热裂解导致低碳数正构烷烃相对富集,代表混合原油但正常原油的贡献较大。