Petroleum streams

Fisher, I.P. and P. Fisher (1974), Analysis of high boiling petroleum streams by high resolution mass spectrometry . Talanta, Vol. 21, p. 867. 

Methylphenol. This phenol, commonly known as o-cresol, is produced synthetically by the gas phase alkylation of phenol with methanol using modified alumina catalysis or it may be recovered from naturally occurring petroleum streams and coal tars. Most is produced synthetically. Reaction of phenol with methanol using modified zeoHte catalysts is a concerted dehydration of the methanol and alkylation of the aromatic ring. 2-Methylphenol [95-48-7] is available in 55-gal dmms (208-L) and in bulk quantities in tank wagons and railcars. 

Aliphatic/aromatic. Copolymerization of aliphatic monomers (terpenes, cyclic C5, and acyclic C5) with the aromatic C9 petroleum stream is used to produce... 

The feed to a distillation tower is normally heated either by indirect heat exchange with hot products and/or in a furnace. The products must be condensed and cooled. This is accomplished in part by heat exchange with other petroleum streams and in part by cooling water exchange. The arrangement and relative... 

Most sulfur compounds can be removed from petroleum streams through hydrotreatment processes, where hydrogen sulfide is produced and the corresponding hydrocarbon released. Hydrogen sulfide is then absorbed in a suitable absorbent and recovered as sulfur (Chapter 4). 

Oxygen compounds in crude oils are more complex than the sulfur types. However, their presence in petroleum streams is not poisonous to processing catalysts. Many of the oxygen compounds found in crude oils are weakly acidic. They are carboxylic acids, cresylic acid, phenol, and naphthenic acid. Naphthenic acids are mainly cyclopentane and cyclohexane derivatives having a carboxyalkyl side chain. 

Deposition of adamantane from petroleum streams is associated with phase transitions resulting from changes in temperature, pressure, and/or composition of reservoir fluid. Generally, these phase transitions result in a solid phase from a gas or a liquid petroleum fluid. Deposition problems are particularly cumbersome when the fluid stream is dry (i.e., low LPG content in the stream). Phase segregation of solids takes place when the fluid is cooled and/or depressurized. In a wet reservoir fluid (i.e., high LPG content in the stream) the diamondoids partition into the LPG-rich phase and the gas phase. Deposition of diamondoids from a wet reservoir fluid is not as problematic as in the case of dry streams [74, 75]. 

Spent caustic solutions from petroleum refining. Petrochemical refineries use caustics to remove acidic compounds such as mercaptans from liquid petroleum streams to reduce produced odor and corrosivity as well as to meet product sulfur specifications. Spent liquid treating caustics from petroleum refineries are excluded from the definition of solid waste if they are used as a feedstock in the manufacture of napthenic and cresylic acid products. U.S. EPA believes that spent caustic, when used in this manner, is a valuable commercial feedstock in the production of these particular products, and is therefore eligible for exclusion. 

Arex A process for removing aromatic hydrocarbons from petroleum streams by extraction with 1-methyl piperidone (N-methyl caprolactam) at 60°C. Developed by Leuna Werke, Germany. 

Catalytic Dewaxing Also called CDW. A hydiocracking process for removing waxes (linear aliphatic hydrocarbons) from petroleum streams by converting them to lower molecular weight hydrocarbons. The catalyst is a synthetic mordenite. Developed by BP two units were operating in 1988. 

Although the superior properties of PEN have been known for many years, the unavailability of the naphthalate monomer has delayed the development of commercial markets, until relatively recently (1995) when the Amoco Chemical Company offered high purity naphthalene-2,6-dimethyl dicarboxylate (NDC) in amounts of up to 60 million pounds per year. This diester is produced by a five-step synthetic route, starting from the readily available compounds, o-xylene and 1,4-butadiene [3], Prior to this, the NDC diester was obtained by extraction of 2,6-dimethylnaphthalene (DMN) from petroleum streams, where it was present in relatively low abundance. Oxidation of DMN to crude 2,6-naphthalene dixcarboxylic (NDA) is conducted by a similar process to that used for conversion of p-xylcnc to purified terephthalic acid (TA), crude NDA is esterified with methanol, and is then distilled to yield high purity NDC. Other companies (e.g. the Mitsubishi Gas Chemical Company) followed Amoco s introduction with lesser amounts of NDC. Teijin [4] has manufactured PEN for many years for its own captive uses in films. 

The domination of PET is likely to continue so long as the raw material costs remain low, and these are currently driven by the cost of oil. Although synthetic fibers use only 1 % of the petroleum stream, they are in competition for that resource with fuels which use up to 50 times as much. Chemical producers already have efforts in place to supply raw materials for PET from renewable biological sources, so it is possible that even the increasing cost of oil will not diminish the dominance of polyester. When contrasted with increasing costs of land and resources for natural fiber production, as food for an increasing population competes for the same land, the use of PET fibers will likely become even more prevalent than today. 

Solid hydrocarbon materials are not observable in process NMR instruments. In order to be observed the molecules under analysis must be entirely in the liquid state and must be above a nominal viscosity threshold. In heavy or waxy petroleum streams the samples must be heated to approximately 80 °C to lower viscosity and ensure melting and solubility of waxy components. 

Genotoxicity. No definite conclusions can be reached from the in vitro human cell and whole animal genetic toxicology studies that have been performed with fuel oils. Data from bacterial in vitro assays are inconsistent (see Section 2.4, Genotoxic Effects). A study of the genotoxicity/mutagenicity of commercially available fuel oils and the various component petroleum streams used in their formulation would be of value. 

A second manufacturing method for acetic acid utilizes butane from the C4 petroleum stream rather than ethylene. It is a very complex oxidation with a variety of products formed, but conditions can be controlled to allow a large percentage of acetic acid to be formed. Cobalt (best), manganese, or chromium acetates are catalysts with temperatures of 50-250 °C and a pressure of 800 psi. 

Reference to Table 4.1 indicates that olefins can be determined by the electrochemical generation in situ of halogens. Bromine is effective for both olefins and sulfur compounds and is the basis for an automatic coulometric titrator for continuous analysis of petroleum streams.17 The basic principle of this instrument is a potentiometric sensing system that monitors bromine concentration in a continuously introduced sample stream. The bromine in the solution reacts with the sample components and causes a decrease in the concentration of bromine. When this decrease is sensed by the potentiometric detection electrodes, the electrolysis current producing bromine adjusts itself to maintain the bromine concentration. Because the sample is introduced at a constant rate, the electrolysis current becomes directly proportional to the concentration of the sample component. Thus, the instrument records the electrolysis current as concentration of sample component and provides a continuous monitor for olefins or sulfur in petroleum streams. 

Both the automatic coulometric titration of petroleum streams and the continuous monitoring of pesticides and sulfur-halogen compounds indicate that the coulometric titrator method is amenable to the automatic maintenance of the concentration of a component in a solution system. A manual version of this approach has been used to study the kinetics of hydrogenation of olefins as well as to determine the rate of hydrolysis of esters.12 The latter system is a pH-stat that is based on the principles of coulometric titrations. Equations (4.9)-(4.11) indicate how this approach is applied to the evaluation of the rate constants for ester hydrolysis. A similar approach could be used to develop procedures for kinetic studies that involve most of the electrochemical intermediates summarized in Table 4.1. The coulometric titration method provides a convenient means to extend the range of systems that can be subjected to kinetic study in solution. 

Common synthetic-based raw materials for surfactant production include ethylene, and propylene. Crude oil consists of a complex mixture of long chain hydrocarbons and aromatic molecules. Natural gas is a mixture of short chain hydrocarbons rich in methane, ethane, propane, and butane. The exact composition of both depends on its source and how it has been processed. Ethylene and propylene are produced by thermal or catalytic cracking of natural gas or aromatic rich petroleum streams. 

ART (2) [Advanced Reformate upgrading Technology] A process for converting reformate (a petroleum stream) directly to a mixture of benzene, toluene, and xylene. The catalyst is a zeolite promoted by a platinum metal. Developed by Zeolyst International and SK Corporation operated in Korea by SK Corporation since 2001. 

Morex A process for removing mercaptans from petroleum streams. Developed by UOP and intended for installation in Conoco s Lake Charles, LA refinery in 2003. 

Generally, past practice has called for evaluating certain portions of the above liquids in existing refinery streams. This led to problems and did not allow for a detailed and comprehensive study of the very nature of the synthetic liquids. A primary purpose of this project was to attempt to define the operable, physical, and chemical nature of the liquids from coal and shale liquefaction, per se, and then contrast and compare with results from processing standard petroleum streams. 

Gasoline is usually produced as a blend of several petroleum streams that boil in the range of naphtha. A typical gasoline might contain 50% by volume of cracked naphtha with benzene content between 0.5 wt% and 2.0 wt% and 25% by volume of catalytically reformed naphtha with benzene content between 1 wt% and 3 wt%. Estimate the cost per gallon of gasoline of reducing the final benzene content to 0.62% by volume. Compositions of other components in the naphtha streams can be found in the patent literature. 

A patent for desulfurization of petroleum streams containing condensed ring heterocyclic organosulfur compounds on the basis of the similar principle was filed by Research and Engineering Company in 2001.58... 

---