尿素络合法分离费托合成产品中的正构烷烃

分别以费托合成直馏柴油和异构柴油为原料,通过尿素/硫脲对正构烷烃和异构烷烃进行分离,从而提高产品附加值。通过尿素或硫脲法分离直馏柴油中的正/异构烷烃实验可以看出,采用尿素法一次脱蜡得到的产品中正构烷烃含量达到97.0%（质量分数,下同）,二次脱蜡得到的正构烷烃含量达到98.0%;通过硫脲法分离正/异构烷烃,产品中正构烷烃含量为96.5%,但硫脲量使用量降低。通过对尿素法分离异构柴油的研究,可以看出尿素量增加有利于降低异构柴油的凝点。对比尿素法和硫脲法的分离结果,可以看出,尿素和硫脲均可与正/异构烷烃反应,但稳定性存在差异。相对而言,尿素与高碳异构烷烃或低碳正构烷烃形成络合物更稳定,硫脲与高碳正构烷烃或低碳异构烷烃形成络合物更稳定。     

制取高辛烷值汽油的综合流程

吸附与工业层析法相结合是从石油馏份和气体冷凝液中制取高辛烷值汽油的有效方法之一。如果这些馏份主要由直链和异链烷烃组成,靠C_5—C_8正烷烃窄馏份的吸附分离,则汽油的产率会大大地下降。虽然未吸附馏份主要由异烷烃和芳烃组成,但反应效率整个是低的。为了提高高辛烷值汽油的产率,在吸附一层析法放大试验装置上装有吸附分离正烷烃的     

尿素脱蜡工艺现状及其发展前景

尿素脱蜡工艺,在制取高纯度的C_(15)~C_(40)正构烷烃,以及低倾点的中间馏份油,如低凝燃料油或特种润滑油等产品方面,有与溶剂脱蜡,分子筛脱蜡等工艺方法不可比拟的优点〔1、2〕.     

芳烃对磺氧化反应的影响

芳烃一般指分子中有一个或多个苯环的烃类,学名叫芳香族化合物。用于磺氧化反应的烃类多是C10－20的烷烃,它们是从粗煤油或粗柴油馏份经尿素络合或分子筛吸附而得。我厂磺氧化反应试验所使用的原料是从柴油馏份用尿素络合而得的重蜡油,碳数分布为C11－21,其中正构烷烃含量多在90%以上,高的可达95%以上,余者为芳烃、烯烃、异构烃等。芳含量多在0．5~1%。据磺氧化反应证明,正构烷烃中若含有10%的芳烃、烯烃、异构烃等杂质,即使经高能的R射线辐照,也不易引起磺氧化反应。     

浅色固体C_5石油树脂通过中试鉴定

C_5馏份是石油裂解生产乙烯的副产品,一座30万吨/年石油裂解制乙烯装置,可产生约3万吨的C_5馏份,其中双烯烃含量达40～50％,余者为单烯烃或烷烃。随着我国石油化学工业的发展,到“七五”末期,每     

石油化工碳五馏份的利用途径

碳五馏份主要是炼油厂催化裂化过程和石油化工厂烃类裂解制乙烯过程的副产品,其数量和组成随来源不同而有很大差别。一座60万吨/年的催化裂化装置,每年可产生5万吨碳五馏份(约占总处理量的8％)。在汽油中含4.3万吨,在液态烃中含7千吨。它的组成以烷烃和烯烃为主,双烯烃含量很低,其中异戊烷和异戊烯各占35%左右,正戊烯约20％。一座45万吨/年的石脑油裂解制乙烯装置,每年可副产7万吨碳五馏份(约占乙烯总量的15%)。它的组份中双烯烃含量大为增高:其中异戊二     

合成脂肪酸皂不愉快气味的脱除

上海轻工业研究所对合脂皂不愉快气味的脱除作了试验。他们主要采用上海制皂厂连续制皂新工艺真空冷却中型设备,进行脱臭试验,并配合进行了尿素络合分离、分馏切割馏份、皂化预处理等其他小型试验,以比较效果,从而在不改变现有原料蜡及生产工艺条件的情况下,提出有效措施,达到改善皂用酸气味与提高产品质量的目的。     

尿素脱蜡装置改型生产轻液蜡

异丙醇水溶液尿素脱蜡装置设计目的是利用尿素分子在一定条件下能够与正构烷烃发生络合反应的特性，以常二线含蜡油为原料，生产高纯度300#重液蜡和低凝柴油。因市场对200#轻液蜡产品的需求旺盛，某公司准备利用现有生产设备，通过改造原料油组成、改变尿液组成、反应终温等工艺指标，使络合反应时的络合物具有一定的选择性，在保证产品质量和收率的前提下，使尿素脱蜡装置顺利改型生产200#轻液蜡和300#重液蜡。     

引进技改

抚顺12万t/a分子筛脱蜡联合炼油装置投产 辽宁省抚顺石油化工公司日前建成并投产一座能力达12万t/a的分子筛脱蜡联合炼油装置,该装置引进美国专利技术,具有世界先进水平。其主要功效是:从石油加工中的煤油馏份中进一步提取合成洗涤剂的生产所需原料——正构烷烃。该类产品目前仍需要花费巨额外汇从国外购头。该装置投产不仅年创利税3,000余万元,且尚节省进口洗涤剂原料所耗外汇5,000余万美元。 王沛熹摘自中国化工报,1995(12):11     

由裂解制乙烯副产轻焦油中用二甲亚砜萃取芳烃的中间试验

前言石油馏份裂解制乙烯副产轻焦油中(C_6—C_8馏份)含有丰富的苯、甲苯、二甲苯等芳烃,一般石油馏份裂解装置的裂解轻焦油产率为裂解原料的10—15％,芳烃产率为裂解原料的5—8％。乙烯是石油化工的基本原料。随着石油化工的发展,乙烯的产量将增加,装置将大型化,因此裂解焦油的综合利用,经焦油中芳烃的分离的重要性越来越显著。     

Simultaneous determination of major characteristic parameters of naphtha by capillary gas chromatography

A method for determining major characteristic parameters of naphthas by capillary gas chromatography was developed to identify the individual hydrocarbons in naphtha and determine the hydrocarbon-type PNA value, the average molecular weight, the carbon-to-hydrogen ratio, the density and boiling point range of naphtha. The method can also be used to analyze other light fractions of petroleum such as natural gas liquid and by-products from petrochemical processing such as raffinate oil. The data obtained by the method had a good agreement with those by other methods. The method was not affected by surroundings conditions when determining boiling point range of light petroleum fractions and can provide with more detailed information. The recovery percentage was 100% when the method used to measure boiling distribution of light fraction. The method was utilized to predict the pyrolytic effect of different naphthas for ethylene production. The prediction had an agreement with the results that were obtained by pyrolysis of naphthas on the Bench Scale Pyrolysis Apparatus (BSPA) made by M.W. Kellogg Company.     

New method for obtaining the distillation curves of petroleum products and coal-derived liquids using a small amount of sample

Based on thermogravimetric principles a new distillation method for petroleum products and coal-derived liquids has been developed. The boiling point distributions of five petroleum fractions (kerosene; 128–228 °C; light gas oil, 178–298 °C; middle gas oil, 200–360 °C; vacuum gas oil, 268–565 °C; and high vacuum gas oil, 305–604 °C) and one highly aromatic coal-tar fraction (wash oil, 180–310 °C) were obtained. The results are in good agreement with those obtained by standard (ASTM) distillation methods. The amount of sample required is very small (≈10 mg) and can be solid or liquid. The experiments at normal pressure were carried out using a specially designed sample holder made of quartz. In the case of high-boiling-point fractions (distillation under reduced pressure) a normal sample holder can be used. The results are automatically recorded as temperature versus weight loss.     

Über die Abtrennung von n-Paraffinen durch Harnstoffaddukt-Bildung

Separation of n-Paraffins by Urea-Adduct Formation Using various procedures for the formation of urea adducts, the determination of n-paraffins in products (solidification point 25°–64°C) containing low, moderate and high concentration of these substances is reported. Theses results are compared with values that are obtained by molecular sieve and antimony pentachloride methods. The authors have established that the determination of n-paraffin by the urea method, as reported in the literature by numerous authors, provides approximate values. The results of the present work indicate that the experimental conditions that are to be employed for the determination of paraffin content by urea-adduct formation, must be adjusted for each type of product after comparing the results obtained by the molecular sieve method. The possibility for the determination of n-paraffins in other petroleum fractions by urea method is discussed.     

蜡油加氢精制-临氢降凝单反应器工艺试验

采用加氢精制-临氢降凝单反应器工艺,以某炼油厂蜡油为原料生产润滑油基础油。结果表明,该工艺能够达到很好的降凝效果,产品370℃润滑油馏分的凝点为-10℃,收率为79.4%,工艺副产少量轻柴油、粗汽油及石油液化气,工艺主要产品为高粘度的润滑油馏分,其凝点降到-10℃以下,副产少量轻柴油、粗汽油及石油液化气。     

Prediction of Liquid Viscosities of Petroleum Fractions

A general equation is proposed for predicting the liquid viscosities of petroleum fzac-riots based on a generalied pseudocompound method in which pure hydrocarbons and undefined hydrocarbon mixtures or petroleum fractions are treated as a hypothetical pure substance called pseudocompound which is chaxacterized only by a boiling point and a density. The equation is tested by using the liquld viscosities of the petroleum fractlons of typical American crude oils and crude oils from major oil producing sreas. Good agreement between the predicted and experlmental viscosities for the petroleum fractions is obtained.     

Prediction of Liquid Viscosities of Petroleum Fractions

   A general equation is proposed for predicting the liquid viscosities of petroleum fractions based on a generalized pseudocompound method in which pure hydrocarbons and undefined hydrocarbon mixtures or petroleum fractions are treated as a hypothetical pure substance called pseudocompound which is characterized only by a boiling point and a density . The equation is tested by using the liquid viscosities of the petroleum fractions of typical American crude oils and crude oils from major oil producing areas. Good agreement between the predicted and experimental viscosities for the petroleum fractions is obtained.     

Structural modeling of petroleum fractions based on mixture viscosity and Watson K factor

Two procedures have been developed for structural modeling of petroleum fractions based on mixture viscosity and Watson K factor. The representative molecules of paraffinic, naphthenic and aromatic hydrocarbons, based upon Ruzicka’s structural model, have been determined for lube-oil cut SAE 10 from Tehran oil refinery. Unlike previous methods, the newly developed procedures do not require time-consuming and costly laboratory data such as true boiling point profile. Good agreement between predictions of the new models and experimental results has been observed. Moreover, the proposed methods take less run-time than previous models due to less experimental and computational complexities. The results indicate that Ruzicka’s procedure, based on vapor pressure, is only applicable for light hydrocarbon mixtures, while the new methods can be applied for structural modeling of a wide range of petroleum fractions. Furthermore, as a result of this study, the application of a vapor pressure constraint leads to a higher degree of accuracy than the earlier suggested constraint, partial pressure, by Ruzicka.     

Pilot Plant Recovery of Soybean Oleosome Fractions by an Enzyme-Assisted Aqueous Process

An aqueous enzymatic procedure for oleosome fractionation from 25 g of soy flour was developed in our laboratory. This fractionation procedure was evaluated with 75 kg using pilot plant equipment to evaluate the effect of the scale-up on the recovery, proximate composition, soybean storage protein profiles, and subcellular microstructure of oleosome fractions. The process included enzymatic hydrolysis, grinding, and centrifugation, respectively. Pilot-scale grinding and centrifugation of the slurry were accomplished with a Stephan^® Microcut mill grinder and a three phase decanter. A blender and swinging bucket rotor were used for the laboratory-scale fractionation. The oleosome fractions recovered in the pilot plant were similar in oil and protein content to those obtained in the laboratory. The pilot-scale process resulted in a significantly higher oil yield of 93.40% as total oleosomes compared to that of 76.83% achieved in the laboratory. Urea–SDS gel electrophoresis of proteins extracted from the oleosomes and supernatant from the pilot-scale fractionation had similar profiles to those obtained in the laboratory. Electron microscopy verified that the structure of isolated oleosomes was virtually identical with that of in situ oleosomes. This work confirms that large-scale fractionation of oleosomes from full fat soybean flour can be accomplished.     

Molecular components-based representation of petroleum fractions

Characterisation of petroleum fractions is the systematic analysis and representation of composition and properties of petroleum fractions. Characterisation methods play an important role in understanding of the physical and chemical behaviour of a petroleum fraction, its individual constituents, and are essential for modelling of refinery processes. In order to comply with the current and future product specifications for cleaner fuels, refineries are employing new processing technologies and more severe operating conditions in existing operating units. Consequently refinery process models are required to capture the chemistry of conversion processes employing characterisation of petroleum fractions at molecular level. In this paper a review of the conventional characterisation methods used for modelling of refinery processes is presented. The molecular type and homologous series (MTHS) matrix representation of petroleum fractions is discussed in detail. The previous work on MTHS matrix representation approach is limited to light petroleum fractions such as gasoline, and takes into account only hydrocarbon molecules. These shortcomings of MTHS matrix representation approach are addressed in this work through the development of a new strategy for estimation of composition and properties of petroleum fractions.     

Methoden zur Verbesserung der Destillation von Tallöl

New Method for the Improvement of Tall Oil Distillation Experimental results are reported on the distillation of tall oil in a pilot plant as well as in an industrial unit. The process involves the use of thin-film evaporators that enable short time of contact. Thus the yield of pitch is decreased. Undesirable side reactions, such as esterification, decarboxylation and polymerization are reduced. The typical characteristics of the fractions obtained have been investigated and correlated with the operational data. It is shown that since the pretreatments of the product such as heating, dehydration and separation of pitch are carried out under very mild conditions, the subsequent fractionation of resin acids and fatty acids into fractions having low content of unsaponifiables can easily be achieved.