Tracking Catalytic Esterification of Naphthenic Acids in Crude Oil by ESI FT-ICR MS

The catalytic esterification reaction was used to decrease total acid number(TAN) of crude oil by converting naphthenic acids to naphthenic acid esters in the presence of Zn-Al hydrotalcite used as the catalyst and glycol used as the reactant. The crude oil and its corresponding esterified oil were characterized by the negative-ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). Six acidic class species, O_2, O_1, N_1, N_2, N_1O_1 and N_1O_2 were assigned in the negative-ion spectrum both in the crude oil and its esterified oil. Among the identified acidic compounds, the O2 class was dominant. The relative abundance of O_2 class species was much higher than other acidic class species in crude oil, while it was significantly decreased after esterification. The most abundant O_2 class species had a carbon number of 30-34 and a double-bond equivalence(DBE) value of 5 before and after esterification. It could be concluded that the naphthenic acids in crude oil can be esterified to lower its TAN value, and each of them seems to exhibit identical esterification efficiency approximately due to the similar DBE versus the-carbon number distribution before and after esterification.

Molecular composition of naphthenic acids in a Chinese heavy crude oil and their impacts on oil viscosity

Most heavy crude oils underwent biodegradation and generated a significant amount of naphthenic acids. Naphthenic acids are polar compounds with the carboxylic group and are considered as a major factor affecting the oil viscosity. However, the relationship between the molecular composition of naphthenic acids and oil viscosity is not well understood. This study examined a “clean” heavy oil with low contents of heteroatoms but had a high content of naphthenic acids. Naphthenic acids were fractionated by distillation and caustic extraction. The molecular composition was characterized by high-resolution Orbitrap mass spectrometry. It was found that the 2- and 3-ring naphthenic monoacids with 15–35 carbon atoms are dominant components of the acid fractions;the caustic extraction is capable of isolating naphthenic acids with less than 35 carbons, which is equivalent to the upper limit of the distillable components, but not those in the residue fraction;the total acid number of the heavy distillates is higher than that of the residue fraction;the viscosity of the distillation fraction increases exponentially with an increased boiling point of the distillates. Blending experiments indicates that there is a strong correlation between the oil viscosity and acids content, although the acid content is only a few percent of the total oil.

Thermal Treatment for Decreasing the Acidity of Crude Oil

Highly acidic crude oil is thermally soaked to investigate how the temperature and time involved affect the removal of organic acid in feedstock. Experimental results indicate that thermal treatment is an effective approach to decreasing acidity and the acid removal rate reaches 80%. Temperature is one of the main factors that determine the acid removal reaction. When the temperature ranges from 420oC to 440oC, the acid removal rate increases with the rise of the reaction temperature, but the increase slows down gradually. At the reaction temperature below 440oC, the long reaction time favors the acid removal. The cracking and polymerization of hydrocarbon molecules take place so that the properties of the crude oil change at the same time when the highly acidic crude is thermally treated.

The Breeding of Hybrid Rape Variety Youyan 924 with Strong Heterosis and High Oil

The rape project of ＂Development and Application of Cabbage Type Rape Hybrids with Strong Heterosis＂ which belongs to National 863 Program aimed to breed the rape variety whose rapeseed yield or oil yield increased more than 10% compared with check （CK） variety, or oil yield increased more than 3 percentage points compared with CK. In the regional trial in the middle react,es of the Yangtze River for two years, the average rapeseed yield and oil yield of Youyan 924 which is a hybrid rape variety respectively reached 2 695.95 and 1 264.35 kg/hm2, which respectively increased by 5.22% and 13.4% compared with those of the other test- ing varieties in the same group, and respectively increased by 10.06% and 23.68% compared with those of Zhongyouza 2 which belongs to CK, thus reaching the standard of hybrid rape variety with strong heterosis; the average oil percentage of the variety in the two years was 46.63%,which increased by 3.44 percentage points compared with that of all the other testing varieties in the same group, and in- creased by 5.14 percentage points compared with that of Zhongyouza 2, and the oil percentage of it in the production testing reached 49.21%. Thus Youyan 924 is a variety with strong heterosis and high oil, moreover, its contents of erucic acid and glucosinolate are 0,25% and 20.27 μmol/g, respectively. From the data aggregation of national regional trial, it has the advantages of high oil yield, high yielding ability, reaching the standards of low erucic acid and low glucosinolate, strong lodging re- sistance, good disease resistance aqd moderate mature period.

Process for Separation of Petroleum Acids from Crude Oil

A new technique for separation of petroleum acids from crude oil was proposed. The method relates to processes for treating acidic oils or fractions thereof to reduce or eliminate their acidity by addition of effective amounts of crosslinked polymeric amines such as polypropylene amine and anionic exchange resins having amino-groups. Petroleum acids contained in the mixture can be extracted by a complex solvent. The results indicate that more than 80 % of the petroleum acids are removed and the process does not cause environmental pollution because all the solvents are recovered and reused in the test.

Advance in germplasm innovation and gene mining of high-oil maize

As one of the 3 worldwide major grain crops, maize is the main source of food, feed and edible vegetable oil. High-oil maize has been selectively bred for many years due to its high oil content and nutritional quality. However, compared with normal maize, the progress of high-oil maize breeding is hindered nowadays. Main problems are scarce of high-oil maize germplasm, conventional breeding methods, and slow genetic research progress on oil content and fatty acid composition. In this study, germplasm innovation and gene mining of high-oil maize were reviewed to provide theoretical reference for genetic breeding and utilization. Several high-oil basic populations have been developed after more than 100 years of selection, which have served as the unique resources for high-oil maize breeding. They have also been used to dissect genetic architecture of oil biosynthesis in maize kernel. Using linkage and association analyses, many QTLs and loci associated with oil content and fatty acid composition have been identified and mapped. In addition, some candidate genes for QTLs have been validated to regulate maize grain oil content and fatty acid composition. Prospect for high-oil maize was also discussed to provide knowledge about genetic mechanism of oil biosynthesis and improvement of kernel quality in maize.

海拔环境对甘蓝型油菜籽粒品质性状的影响

本文通过研究不同海拔环境下甘蓝型油菜籽粒品质性状变化规律,旨在为高海拔地区甘蓝型油菜引种及品质育种提供参考。以11个甘蓝型油菜品系为试材,在甘肃兰州、青海西宁和西藏拉萨试验点种植,比较分析3个海拔环境对油菜籽粒芥酸、硫苷、含油量、棕榈酸、C18脂肪酸的硬脂酸、油酸、亚油酸、亚麻酸品质的影响。结果表明,随海拔高度的增加,甘蓝型籽粒含油量呈增加趋势,品系间表现一致,变异系数为0.0822;芥酸含量均在高海拔拉萨种植后明显升高,硫苷含量在高海拔种植比低海拔种植均有不同程度的增加,其两者的变异系数较大,分别为0.3364、0.4920。相关性分析显示,芥酸含量、含油量与海拔呈极显著正相关,相关系数分别为0.865、0.750,硫苷与海拔呈显著相关性,相关系数为0.428。研究发现,高海拔有利于含油量、芥酸和硫苷的积累,纬度的升高有利于棕榈酸和硬脂酸的积累,温度的变化是多数品质含量变化的主要因素。

甘蓝型高油分杂交油菜新品种宝油187的选育与应用

【目的】培育高产、高油及耐密植油菜新品种,为高油高产优质油菜品种的应用提供种质选择。【方法】贵州省油菜研究所利用隐性核不育两系D418AB作母本,以恢复系YD84R作父本,于2023年育成高油分双低杂交油菜新品种宝油187(农业农村部登记编号:GPD油菜〔2023〕520162)。【结果】宝油187在长江上游区域试验中平均产量207.7 kg/667m^(2),比对照(蓉油18)增产4.09%;平均产油量104.6 kg/667m^(2),比对照增产22.18%;平均生育期215 d。在长江中游区域试验中宝油187平均产量210.3 kg/667m^(2),比对照(华油杂50)增产7.32%;平均产油量107.6 kg/667m^(2),比对照增产10.29%;平均生育期215 d。经农业农村部油料及制品质量监督检验测试中心检测,宝油187芥酸为0.05%,硫甙为20.45μmol/g饼,含油量为51.94%。【结论】宝油187中抗菌核病,丰产性好,耐密植,高油分,适宜在贵州、四川、重庆、湖南、湖北和江西等冬油菜区推广应用。

同心双锥型高含水油水两相管式旋流分离特性

针对常规切向入口旋流分离器处理高含水采出液效果较差以及分离效率受入口流速影响较大等问题,率先提出中心细锥体和外筒倒锥体的同心双锥型油水两相管式分离构造。综合高含水率、大处理量等因素综合作用,建立油-水两相分离Mixture多相流模型和流场RNG k-ε湍流模型,并采用SIMPLE压力-速度耦合算法对模型进行求解,依据求解结果揭示同心双锥型管式分离腔室内旋流场的动态分布状况,量化分析中心锥角度变化对油水两相管式分离效率的具体影响程度,探究油滴粒径、入口流速等参数对管式旋流分离性能的作用机制。结果表明,随中心锥角度不断增加,同心双锥型管式旋流分离效率呈现先升高再降低的变化趋势,最佳中心锥角度为82°;增大油滴粒径能升高油池聚集性,有利于提升分离性能,当油滴粒径由0.3 mm增至0.6 mm时,分离效率由85.6%提至94.5%;入口流速对分离效率的影响相对较小,当入口流速由5 m·s^(-1)提至11 m·s^(-1),分离效率仅由93.3%升至96.9%,流速相差6 m·s^(-1)时,分离效率仅相差3.5%。

高酸原油选择适合破乳剂的实验分析研究

现有破乳剂均有一定的局限性,对于特高含水的水包油型乳状液,存在脱水率低、脱水温度高、脱水速度慢等缺点,因此,针对不同地区的不同原油选择适合的破乳剂有着重要意义。基于此,考察了影响破乳剂性能的各种反应条件,在实验温度90℃和用量为10×10^(-6)破乳剂的条件下,通过瓶试脱水法,考察评价石油磺酸盐对破乳剂的影响。研究表明,石油磺酸盐明显降低了破乳剂在高酸原油中破乳脱水作用。

超高酸原油中石油酸分子组成表征与腐蚀性预测

采用傅里叶变换离子回旋共振质谱法对国内某超高酸原油及其馏分油中的石油酸分子组成进行表征,研究Q345R、1Cr5Mo、304L和316L 4种典型炼油装置用材在不同酸值(Total acid number,TAN)油品中的静态腐蚀行为,并构建高温酸腐蚀预测模型。结果表明,TAN为10.403 mg KOH/g、含2个氧原子的O2类石油羧酸是石油酸的主要成分,其中二环、三环环烷酸和单环芳香羧酸含量相对较高。168 h静态挂片腐蚀实验结果表明,4种材质腐蚀速率均随温度升高而增加,高于280℃后增加趋势逐渐变缓。不同材质微观腐蚀形貌存在显著差异:Q345R整体呈现均匀腐蚀形态;1Cr5Mo表面形成密集蚀坑;304L表面分布少量浅表性腐蚀区;316L仍可见金属光泽。根据腐蚀速率结果,考虑脂肪酸、环烷酸和芳香酸与金属的结合作用,将石油酸分子组成作为腐蚀预测模型的修正项,采用Levenberg-Marquardt(LM)算法拟合模型参数,模型相关系数R 2大于0.950,均方根误差RMSE小于0.089,可实现超高酸原油腐蚀性的早期预测,为指导超高酸原油加工装置合理选材、制定检维修计划提供支持。

加工高酸原油的常压塔塔顶挥发线腐蚀及防护

某加工高酸原油的常减压装置的常压塔塔顶(常顶)挥发线,在线腐蚀探针监测数据长时间超过控制指标,检修发现常顶挥发线有较多蚀坑减薄部位,存在腐蚀泄漏风险。通过分析定点测厚情况、探针腐蚀速率、探针腐蚀垢物、常顶含硫污水腐蚀介质,结合常顶挥发线中介质流速的计算,识别出两个加剧腐蚀过程的主要因素:常顶挥发线介质中存在浓度高达390~600 mg/L的多种小分子有机酸,以及塔顶介质的高流速。针对常顶挥发线的腐蚀问题,采取了两项有针对性的措施:控制常顶石脑油流量不超过150 t/h,以减少腐蚀介质在系统内的积累;优化中和剂的选型,确保中和剂能够有效中和系统中的酸性物质,从而显著降低腐蚀速率。通过实施这些工艺措施,改善了常顶挥发线的腐蚀情况,延长了设备的使用寿命,确保了装置能够长期、稳定、安全地运行。

高酸值原油环烷酸的结构组成

对苏丹Fula-North-3B原油及馏份油中环烷酸的酸值、结构、分子量分布等进行了分析测试和研究. 结果表明:苏丹Fula-North-3B原油中环烷酸的酸值(以KOH计)在10~14 mg/g之间,结构均以一、二、三环为主,在350oC以上,除一、二、三环外,还含有一定量的四、五环的环烷酸. 芳环含量很少, 烯烃双键含量也很少,环烷酸的构成主要是一元酸. 环烷酸的分子量分布情况与馏份的沸程趋势一致. 随着馏份变重,酸值增加、环烷酸的平均分子量增大、分布变宽、碳数范围增加.

高酸原油热处理脱酸的研究

考察了不同温度、时间的热处理反应对脱除高酸原油中石油酸的影响。试验结果表明 :热处理是降低原油酸值的有效方法 ,其脱酸率可以达到 80 %以上。温度是脱酸反应的主要影响因素 ,在反应温度为 4 2 0～ 4 4 0℃时石油酸的脱除率随温度升高而增加较快 ;当反应温度高于 4 4 0℃时 ,原油脱酸率随温度升高增加变缓。在低于 4 4 0℃的反应温度下 ,反应时间延长有利于提高脱酸率。在热处理脱酸反应的同时 ,原油烃类分子发生裂化缩合反应 ,引起原油的物理化学性质发生变化。

高酸原油催化脱酸工艺研究进展

介绍了高酸原油催化加氢脱酸法、催化热解脱酸法和催化化学反应脱酸法,展望了该工艺的应用前景。提出了根据高酸原油的特点及其腐蚀特性,开发催化脱酸工艺的发展方向。

苏丹高酸值重质原油脱酸新工艺探索

采用醇、胺等复合溶剂,对高酸值原油中的环烷酸进行抽提,详细讨论了抽提温度、搅拌速度、相分离时间及反应时间等因素对脱酸的影响.实验结果表明,该方法有效地克服了乳化现象严重的缺点,经复合溶剂抽提,一次脱酸率可达70%以上.

重质高酸原油酯化脱酸催化剂的研究

高酸原油的加工是炼油厂面临的一大难题。笔者开发了一种用于高酸原油酯化脱酸的固定床酯化催化剂,使高酸原油中的环烷酸与甲醇反应生成环烷酸甲酯以降低原油的酸值和腐蚀性。结果表明,SnO是催化酯化脱酸催化剂的有效活性组分,适当增大催化剂的孔径可提高原油的酯化脱酸率。该催化剂应用于中海绥中36-1高酸原油,可有效降低原油的酸值,在反应温度300℃、醇/油质量比0.02,体积空速1.0 h-1时,可使原油的酸值由2.8 mgKOH/g降低到0.34 mgKOH/g,能够满足炼油厂加工的需要。

ZnMgAl-HTlc催化酯化高酸原油脱酸

在ZnMgAl类水滑石催化剂的作用下,辽河高酸原油中的环烷酸与乙醇反应生成环烷酸乙酯,可有效地降低原油的酸值,并降低其对设备的腐蚀性。实验结果表明,ZnMgAl类水滑石是一种有效的酯化脱酸催化剂,催化酯化反应后其结构基本未变。在醇/油质量比0.02、反应温度250℃、反应时间60 min、原油与ZnMgAl类水滑石催化剂质量比为100的条件下,催化酯化反应可使辽河高酸原油的酸值由3.61 mg KOH/g降至0.15 mg KOH/g,能够满足炼油厂在不进行材质升级条件下加工高酸原油的需求。

渤海原油环烷酸分布与组成结构

对渤海PL19-3原油环烷酸分离提纯后,采用红外光谱、元素分析、气相色谱质谱等手段对环烷酸组成结构及分布进行分析。结果表明:渤海PL19-3原油中石油酸不仅存在于柴油馏分中,在减压蜡油中仍然有较高含量;环烷酸主要是以一环、二环、三环为主,芳环含量较低,并随馏分变重结构趋于复杂。

高酸原油直接催化脱酸裂化成套技术开发和工业应用

利用分子模拟技术和量子化学理论研究了各种石油酸中原子的电荷分布、键级和在不同催化材料上的反应行为,发现羧基可从石油酸分子中脱除,生成无腐蚀性的CO_2和烃类化合物,尤其在酸性裂化催化剂作用下脱羧基速率更快、更彻底。开发了高酸原油经脱盐、脱水后直接进入催化裂化提升管反应器与高温新型催化剂接触,瞬间汽化,同时实现脱酸和裂化反应,生成高价值石油产品的新工艺。工业应用结果:催化脱酸率大于99%,汽油、柴油可直接作为产品的调合组分,在平衡催化剂上金属污染物总量达40 620μg/g(其中镍为24 000μg/g)时,总轻油收率比常规加工技术提高1.36百分点,能耗(相对于原油)降低271.7 MJ/t,对工业应用装置没有特殊防腐要求。为炼油企业扩大原油资源选择范围、降本增效提供了有效技术保障。