Coal liquids, properties

Selected Properties of the Motor Gasoline and Diesel Fuel Refined from Fe-HTFT Syncrude and Coal Liquids at Sasol 2, Which Were Marketed as Final Products in South Africa in the 1980s... 

The cracking of the BMO gave a poor result mainly due to the low H/C-ratio (see Table III). Hemler and Wilcox (29,30) catalytically cracked coal liquids, hydroprocessed at different severities, and found that the conversion increased and the selectivity improved with increasing severity of hydroprocessing. Hydroprocessing the BMO at more severe conditions should improve the cracking properties of this oil. 

Catalysts for coal liquefaction require specific properties. Catalysts of higher hydrogenation activity, supported on nonpolar supports, such as tita-nia, carbon, and Ca-modified alumina, are reasonable for the second stage of upgrading, because crude coal liquids contain heavy polar and/or basic polyaromatics, which tend to adsorb strongly on the catalyst surface, leading to coke formation and catalyst deactivation. High dispersion of the catalytic species on the support is very essential in this instance. The catalyst/support interactions need to be better understood. It has been reported that such interactions lead to chemical activation of the substrate 127). This is discussed in more detail in Section XIII. 

Table II. Properties of Crude and Upgraded Coal Liquids... 

It is for these reasons that we have initiated this correlative study of peat petrography and peat industrial-chemical (coal quality) properties. Note that the information reported herein represents preliminary results based on a limited number of different types of peats that were analyzed for only a few coal quality tests (i.e., proximate analysis, ultimate analysis, and BTU content). Future studies will involve measurement of other petrographic parameters and include other industrial analyses (such as, gas and liquid yields, physical properties, organic chemical yields, and so forth). 

This reactor allows easy data collection for high-temperature, high-pressure reaction systems that have difficult flow properties. This includes reactants that are solid at room temperature or mixtures of solids and liquids. Typical reactions performed in autoclaves are coal liquefaction, petroleum residuals and coal liquids upgrading, and high molecular weight hydrogenation experiments. 

Quinlan, C.W. Siegmund, C.W., Combustion Properties of Coal Liquids from the Exxon Donor Solvent Process, paper presented at the ACS National Meeting, Anaheim, CA., March 14,1978... 

We have our work divided into process engineering, process chemistry, catalysis, and support technology. As an example, one of the indirect liquefaction projects, tube wall reactor, deals with the design and operation of high thermal efficiency catalytic reactors for syn-gas conversion. Other activities are coal liquefaction properties of coal minerals, the role of catalysts, coal liquid product stability, and environmental impact—to name a few. 

Table V. Estimated thermodynamic properties of coal and coal liquids for H-Coal system...

Gray, J. A., et al., "Selected Physical, Chemical, and Thermodynamic Properties of Narrow Boiling Range Coal Liquids," paper presented to the AIChE Fall 1981 Annual Meeting, New Orleans, Nov. (1981). 

TABLE I PHYSICAL AND CHEMICAL PROPERTIES OF COAL LIQUIDS ... 

Quinlan, C. W. and Siegmund, C. W., "Combustion Properties of Coal Liquids From the Exxon Donor Solvent Process", ACS Meeting Anaheim, California, March, 1978. 

Coal Liquids and Shale Oil. Some properties of five coal liquids and a hydrotreated shale oil are given in Table I, including sulfur, nitrogen, acid and base contents, and distributions by boiling range. Ring-number... 

Table VI. Preliminary Data for Coal Liquid Prepared from Illinois No. 6 Coal and Typical Properties of Original Coal...

Experience with the development of the solvent-refined coal (SRC) process had suggested that raw anthracene oil was a suitable coal liquid for initial catalyst studies hence some data were obtained using this type of oil. A filtered oil obtained from the COED process developed by FMC Corporation also was used in these studies. The properties of these two oils are given in Table I. The total nitrogen concentration in the raw anthracene feed oil was 0.97 wt % and the FMC oil contained 1.13 wt % nitrogen. Both liquids contained negligible quantities of ash materials. 

Many studies have depicted coal liquefaction in terms of the sequential progression through the series of intermediate steps from preasphaltene to asphaltene to oil. Other approaches have emphasized the changes in functional groups over the course of liquefaction. Our recent work (20, 21, 23, 24, 28) has concentrated on the fate and changes in the asphaltene fraction of liquid products as the severity of hydrotreatment was varied. In the course of this work, we have developed certain viewpoints on the importance of the character of asphaltenes to physical properties of coal liquids and the relationship of processing history to asphaltene character. What follows is an overview of what we feel are the more important observations. 

Retzekas, E., Voutsas, E., Magoulas, K. andTassios, D. (2002) Prediction of physical properties of hydrocarbons, petroleum, and coal liquid fractions. Ind. Eng. Chem. Res., 41, 1695-1702. 

The relationships among hydroconversion of the coal liquids, sulfur distribution, and other important fuel properties still need to be evaluated. They are part of the S W-Gulf development program now under study. This paper summarizes some of the preliminary investigations carried out as a prelude to the development program. Data on reactions by which aromatic molecules are converted to gas are reviewed and correlated consideration is also given to the formation of aromatic molecules during pyrolysis of hydrocarbons. 

The properties of manufactured graphites are determined by the microstructure of the carbonaceous mesophase which is formed during pyrolysis, usually between the temperatures of 370 C and 500°C. The characteristics of the final product can be measured in a qualitative way by examination of the mesophase micro-structure. Several coal liquid asphaltene and petroleum pitch samples have been screened in this way to determine their suitability as precursors for graphite materials. The physical and chemical properties of the mesophase formed from the samples and their pyrolyses residues were studied(1). It was found that the phenolic oxygen present either in the precursor or by addition during heat treatment suppresses mesophase formation by crosslinking and preventing the development of fluidity(2J>... 

The next most abundant component of neutral oil consists of liquid olefins. The olefins are reactive and tend to undergo polymerization, oxidation, and other reactions causing changes in the properties of the product with time. On the other hand, olefins are excellent raw materials for the manufacture of synthetic polymers and other chemicals and, thus, can be valuable chemical byproducts in coal liquids. 

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