Study on Separating Naphthenic Acids from Diesel Fuel by Microwave Irradiation

The microwave technology was introduced to separate naphthenic acids from diesel fuel. Thedecrease of zeta-potential of electric double layer on the W/O interface and the reduction of diesel fuelviscosity were responsible for the accelerated separation of naphthenic acids under microwave irradiation.The influences of dosage of alkali compound solvent (Mp/MT), irradiation pressure, irradiation time,irradiation power, the settling time and oil phase-to-solvent phase volume ratio (O/S) had been investigated.The optimum process conditions for the refining process were determined. The removal of naphthenicacids reached 98.4% when the optimum conditions were proposed as follows: Mp/MT=1.5, 0.05MPa, 6 min,375W, 25min and O/S=10, respectively. The diesel recovery could reach 99.3% and the quality of thetreated diesel oil was good enough to meet the specification of GB252-2000.

Identification and Characterization of Sulfur Compounds in Straight-Run Diesel Using Comprehensive Two-Dimensional GC Coupled with TOF MS

The solid-phase extraction using Pd-Al2O3 as the stationary phase was employed to pre-separate the sulfur compounds in straight-run diesel. The isolating effect was evaluated quantitatively by gas chromatography with a sulfur chemiluminescence detector to harvest a satisfactory result. The identification of the structure of sulfur compounds by comprehensive two-dimensional gas chromatography coupled with the time-of-flight mass spectrometry indicated that cyclo-sulfides, benzothiophenes, dibenzothiophenes, dihydro-benzothiophenes and tetrahydro-dibenzothiophenes were included in straightrun diesel obtained from the Arab medium crude(AM). A total of 259 individual compounds were detected and their molecular structures were identified. The analytical method was approved as an effective way to characterize the composition of sulfur compounds, which reduced the interference of other compounds, facilitated the data presentation and provided more detailed information about molecular composition of sulfur compounds.

Study on Laboratory Method for Refining of SR Diesel Fuel

The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 20% at a dosage of 17 mL of the solvent and a temperature of 30℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel fraction.

高酸原油柴油馏分中石油酸结构组成分析

通过碱洗法分离柴油馏分中的石油酸,对石油酸进行甲酯化后采用红外光谱、气-质联用、核磁共振波谱仪和电喷雾电离源质谱分析其结构组成。实验结果表明,蓬莱、多巴、辽河3种高酸原油的柴油馏分中有机羧酸的组成以一环环烷酸、二环环烷酸、三环环烷酸为主,基本占有机羧酸的60%以上;3种柴油230～320℃馏分中石油酸碳数分布在8～22之间;320～350℃馏分中石油酸碳数分布在11～28之间;随着柴油馏分沸点增加,脂肪酸、三环环烷酸和烷基苯酸含量升高,一环环烷酸、二环环烷酸含量降低。

柴油脱除环烷酸精制工艺研究进展

综述了柴油脱除环烷酸精制工艺的研究进展。针对传统的碱洗电精制脱酸方法中出现的乳化现象 ,介绍了通过调整工艺参数、添加破乳剂或低分子质量的环烷酸、Na2 SO4和低分子醇等方法来优化现行的碱洗电精制工艺以解决乳化的问题。同时针对传统脱酸方法的不足 ,讨论了氨法、溶剂法、吸附分离法和微波辐射法等柴油精制同时回收环烷酸的新工艺 ,并对各工艺的优点和存在的问题进行了评价。

直馏柴油脱酸工艺研究进展

综述了直馏柴油脱酸方法的发展。氨法化学萃取是目前直馏柴油脱酸工艺的研究热点 ,能否取代直馏柴油碱洗电精制—硫酸中和法工艺 ,其关键在于新型破乳剂、高效率萃取设备和三相分离器的开发。介绍了作者开发的SW - 1破乳剂在直馏柴油氨精制工艺中的应用研究。

络合萃取法精制直馏柴油的研究

针对直馏柴油碱洗脱酸、溶剂脱酸和加氢脱酸精制工艺存在的问题 ,首次采用络合萃取法对直馏柴油进行精制 ,可同时获得精制直镏柴油和环烷酸产品。实验室研究表明 ,本方法流程简单 ,无废液排放 ,精制柴油质量达到GB2 52— 77质量标准。

微波辐射柴油脱酸精制

介绍了一种新的柴油脱酸精制方法———微波辐射法。考察了精制过程中的最佳实验条件。在V(NaOH) /V(Diesel) =0 2 5、反应体系压力 0 0 5MPa、恒压辐射时间 5min、微波辐射功率 375W、静置时间 2 5min的条件下 ,可将柴油的酸度由 90 7mgKOH/ 10 0ml降至 3 99mgKOH/ 10 0ml,达到国家标准GB2 5 2 93的优质柴油质量要求 (酸度小于 5mgKOH/ 10 0ml)。该精制过程对柴油性能无影响 ,回收率达到 99 7% ;同时副产环烷酸 ,其粗酸值为 182 5mgKOH/ g ,中性油含量为 34 2 %。该精制过程省时、耗电量小 ,预期对环境友好。

胜华直馏柴油的固定床催化酯化脱酸

针对柴油碱洗脱酸精制易乳化、收率低的问题，研究了催化酯化脱酸的技术来替代柴油碱洗脱酸。考察了在固定床催化剂存在下，影响柴油酯化脱酸的因素，并评价了酯化脱酸技术的经济性。结果表明，反应温度、空速、醇／油质量比、甲醇水含量等是影响柴油酯化脱酸的重要因素。反应温度高、空速降低、加大醇／油质量比有利于酯化反应的进行。甲醇中水的质量分数低于5％时，对酯化反应影响大，随水含量的增加，脱酸率显著降低；水的质量分数在5％～10％范围，脱酸率不再随水含量的增加而变化。对胜华直馏柴油来说，在反应温度280～300℃、反应空速1．5h^-1、醇／油质量比0．01条件下，脱酸效果明显。直馏柴油酯化脱酸比碱洗脱酸具有更好的经济效益。

高酸度柴油微波辐射精制的研究

介绍了微波辐射法柴油脱酸的原理。采用正交设计法确定柴油微波脱酸的最佳工艺条件,研究了各因素对脱酸效果的影响。在最佳工艺条件下:碱性溶剂用量为理论用量的1.4倍,剂油体积比0.25:1,辐射压力0.06 MPa,恒压辐射时间5 min,辐射功率300 W,可将柴油酸度(KOH)由1 704 mg／L降至23.9 mg／L,达到国家规定的GB 252-2000质量标准,柴油回收率达99.3％。该精制过程无需破乳剂,具有清洁、高效、节能的优点。

微波作用下柴油脱酸及其反应动力学

在微波作用下,以辐射时间、辐射功率和辐射压力,研究了微波碱精制法柴油脱酸的工艺条件,在辐射时间5min,辐射功率375W,辐射压力0.05MPa条件下,柴油脱酸率和油品回收率分别达到99.07%和98.62%。柴油指标满足GB252-2000标准。确定了剂油体系在微波作用下的升温性能,并根据精制过程中环烷酸含量的变化,提出了微波辐射柴油脱酸的非等温反应动力学模型。

环烷酸铈消烟助燃剂改善内燃机有害排放的研究

消除柴油机排放污染应当主要限制柴油机颗粒排放水平。研究具有助燃与消烟作用的柴油添加剂自然成为降低柴油机颗粒排放的重要途径。通过台架试验考察环烷酸铈消烟助燃剂加剂前后发动机的排气烟度、速度特性、负荷特性,以及排气温度等指标,结果表明环烷酸铈消烟助燃剂可降低内燃机排放中的NOx,CO化合物或碳烟等有害物质,特别对碳烟、NOx排放平均下降幅度较大。

直馏柴油溶剂抽提精制

去除直馏柴油中的环烷酸，采用加氢精制法成本高，且氢源不足；采用碱洗法则损失大，污染严重。为此采用以助溶剂和溶剂组成的复合溶剂抽提方法脱除直馏柴油中的环烷酸，并对抽提的工艺条件进行了实验室研究。结果表明，采用单级抽提，剂油比为1～2：10，酸去除率达80％以上，柴油的回收率达99％以上，精制后柴油酸值合格，还可副产环烷酸。溶剂及助溶剂均可回收利用，不污染环境。

直馏柴油脱除环烷酸精制新技术研究

在微波作用下,以辐射时间、辐射功率和辐射压力,研究了微波碱精制法直馏柴油脱酸的工艺条件,在辐射时间5min,辐射功率375W,辐射压力0.05MPa条件下,柴油脱酸率和油品回收率分别达到99.07%和98.62%。精制后油品酸度降低到0.57mgKOH/100mL,柴油性能指标满足GB252 2000轻柴油国家标准。与传统方法相比,微波辐射法无需破乳剂和高压电场。精制过程无乳化现象产生,有利于环境保护。

直馏柴油绿色脱酸技术的实验研究

The green deacidification technology of diesel by the ammonia-alcohol method without using strong acid and strong base can achieve zero-emission.But it has some problems,such as requiring larger amounts of ammonia and solvent,and higher energy consumption of regeneration solvent.To overcome the shortcomings of the ammonia-alcohol method,this paper experimentally studied the green deacidification technology of diesel by the ammonia-alcohol method,which used low-temperature coalescence filtration in a self-made experimental device.The effects of coalescence filtration temperature,amount of ammonia,alcohol consumption,volume ratio of solvent to oil on the deacidification process,material regeneration of coalescence filtration,deacidification’s turndown ratio and the product quality of naphthenic acid were studied.The results showed that under the optimum operation condition,the acidity of straight-run diesel could decrease from 62.9 mg KOH·(100 ml)-1 to 4.2 mg KOH·(100 ml)-1,the acid removal rate was as high as 93.3%,and product recovery could reach 98.6%.After refining,the quality of diesel could meet industry requirements [acidity X<7.0 mg KOH·(100 ml)-1],and raw acid value of naphthenic acid could meet No.2 acid standards of SH/T 0530—92.This method had the advantages of simple technological process,low operating temperature of deacidification,less ammonia and solvent consumption,low solvent regeneration energy consumption and higher turndown ratio.

乙醇—水萃取精制直馏柴油的研究

针对直馏柴油碱洗电精制和硫酸中和法回收环烷酸间歇工艺存在的问题，本文首次采用乙醇—水作为萃取剂，对直馏柴油进行萃取精制，可同时获得精制直馏柴油和环烷酸产品。实验室研究表明，本方法不产生乳化现象，不需要高压电场，油剂分相快，不腐蚀设备，无废液排放，操作费用低，对直馏柴油的萃取精制已达到碱洗电精制的效果，完全克服了现有工艺的缺点。

微波作用下直馏柴油脱酸新方法的研究

用微波辐射的方法对锦西炼油厂生产的直馏柴油进行了脱酸精制试验 ,并考察了精制过程中的最佳试验条件。当剂油体积比为 0 .2 5∶1、压力为 0 .0 4MPa、恒压辐射时间为 5min、微波功率为375W、静置时间为 2 0min时 ,可将柴油的酸度由 89.5mgKOH/ 10 0ml降至 3.78mgKOH/ 10 0ml,达到国家规定优质柴油质量标准 (小于 5mgKOH/ 10 0ml) ,且精制过程对柴油性能无影响 ,回收率达到 99.6 %。该精制过程节省时间、耗电量小 ,有利于环境保护。

不同力场对柴油脱酸效果的影响

分别研究了重力场、高压电场和离心力场对柴油脱酸效果的影响。结果表明 ,重力场所需分相时间最长 ,脱酸效果最差 ;高压电场次之 ;离心力场中的分相时间最短 ,当离心机转速为30 0 0r/min时 ,分相时间为 6 0s即可获得很好的分相效果和脱酸效果 ,且设备利用率高。另外 ,离心力场还具有一定的破乳作用 ,在很大程度上降低了两相间的夹带 ,增加了环烷酸的萃取率 ,减少了柴油的损失。

聚乙烯胺用于直馏柴油脱酸的实验研究

采用以聚乙烯胺(PVAm)作主剂的脱酸剂对直馏柴油进行脱酸实验,考察柴油脱酸过程中主要因素的影响。结果表明,在脱酸剂中PVAm与原料油中环烷酸的摩尔比为5.0、剂油体积比为0.02、反应温度和相分离温度均为50℃、反应时间为20 s、相分离时间为60 min、萃取级数为3的操作条件下,脱酸剂可将苏丹柴油酸度从102.7 mgKOH/(100 mL)降至6.0 mgKOH/(100 mL),脱酸率高达94.2%,精制油收率达到99.6%,精制油质量达到GB 252—2000产品质量指标。脱酸剂经高温水解再生,可以重复使用。此脱酸剂用于直馏柴油脱酸具有脱酸剂用量小、可循环利用、再生能耗低、绿色环保等优点。

柴油脱酸工艺研究新进展

综述了柴油脱酸工艺研究新进展,分析了传统脱酸工艺存在的各种问题,对新的脱酸方法作了介绍,着重介绍了目前已工业化的西南石油大学(SWPU)开发的馏分油脱酸剂技术,开发绿色脱酸工艺将是柴油脱酸研究的重点。