Exxon Donor Solvent process development

The development of three-phase reactor technologies in the 1970 s saw renewed interest in the synthetic fuel area due to the energy crisis of 1973. Several processes were developed for direct coal liquefaction using both slurry bubble column reactors (Exxon Donor Solvent process and Solvent Refined Coal process) and three-phase fluidized bed reactors (H-Coal process). These processes were again shelved in the early 1980 s due to the low price of petroleum crudes. 

Other processes have been developed in recent years, especially during the decades of the 1960s and 1970s, to produce liquid fuels from coal. Examples include the H-Coal, Mobil M, Solvent Refined Coal, and Exxon Donor Solvent processes. 

Char Oil Energy Development Process U.S. Department of Energy Exxon Donor Solvent Process fluidized bed combustion hydrogenated anthracene oil hydrogenated phenanthrene oil Hydrocarbon Research, Inc. 

W. R. Eppedy and J. W. Taunton, "Exxon Donor Solvent Coal Liquefaction Process Development," paper presented at Coal Dilemma II ACS Meeting, Colorado Spriags, Colo., Feb. 12, 1979. 

Several processes progressed to demonstration scales but have not been commercialized, primarily because of economic inabiHty to compete with available petroleum products. The H-Coal process developed by Hydrocarbon Research, Inc. was demonstrated at Catiettsburg, Kentucky using a 545 t/d plant and DOE support. The Exxon donor solvent Hquefaction process was not commercialized either. 

W. P. Epperly and T. W. Taunton, "Exxon Donor Solvent, Coal Liquefaction Process Development", Proceedings of the 13th Intersociety Energy Conversion Engineering Conference, Vol. 

Exxon Donor Solvent Also known as EDS. A coal liquifaction process in which coal in solution in tetrahydronaphthalene is hydrogenated, using a cobalt/molybdenum/alumina catalyst. So-called because the hydrogen is donated by the tetrahydronaphthalene to the coal. Developed from the Pott-Broche process. Piloted by Exxon Research Engineering Company in the 1970s and operated at 250 ton/day in the Exxon refinery in Baytown, TX, from 1980 to 1982. 

The Exxon Donor Solvent (EDS) Process, developed by the Exxon Research and Engineering Co., differed from the typical process in that, before being recycled, the solvent was hydrogenated in a fixed-bed reactor using a hydrotreating catalyst, such as cobalt or nickel molybdate. Exxon found that use of this hydrogen donor solvent with carefully controlled properties improved process performance. Exxon developed a solvent index, based on solvent properties, which correlated with solvent effectiveness. 

The relative dimension of the three systems are shown in Figure IV. Combustion test data has been collected on a large number of raw and hydrotreated product samples from the SRC-I, SRC-II, Exxon Donor Solvent, H-Coal, and other processes under development. Figure V is a plot of N0X level versus turbine inlet temperature for these fuels. The actual levels of N0X are related to the actual piece of equipment utilized for the test series but the relative rankings are consistent among the various types of equipment. 

Exxon Donor Solvent, Coal Liquefaction Process Development... 

This paper describes the status of the development of the Exxon Donor Solvent (or EDS) coal liquefaction process. It includes an overview of the jointly funded project and a brief description of the EDS process. It also includes a discussion of the project status, including a description of coal feed flexibility, hydrogen and fuel gas production alternatives and the progress in the construction of the 250 T/D pilot plant. Other communications have covered the R D program, the outlook for commercialization, and the organization of the EDS Project (1,2, 3,, 5, 6, J) ... 

Epperly, W.R. Taunton, J.W., Status and Outlook of the Exxon Donor Solvent Coal Liquefaction Process Development, paper presented at the Fifth Energy Technology Conference, February 27 - March 1, 1978, Washington, D.C. 

The direct liquefaction technologies, which include Solvent Refined Coal, Exxon Donor Solvent and H-Coal processes have never been operated at a commercial scale. As discussed yesterday, these processes are not at advanced stages of development. The products from direct liquefaction processes are basically boiler fuels or synthetic crudes that could potentially be upgraded to... 

In the 1960s, two direct coal liquefaction processes were under development in the U.S. the Exxon Donor Solvent (EDS) process and the H-Coal process. The distinguishing feature of the EDS process was a separate solvent hydrogenation step to carefully control the hydrogen donor characteristics of the solvent. The most important feature of the H-Coal process was the emulated bed reactor in the process. 

The Exxon donor solvent, direct liquefaction process also used hot oil drying. In this process, LRC is dried by a high-pressure hydrogenation reactor contact with hot recycle hydrogen donor solvent prior to entering. Unfortunately, no data were developed for solvent recovery after drying becanse the dried coal and vehicle solvent were reacted immediately with hydrogen in the Uqnefaction reactor. 

Similar to the SRC version is the JExxow-Donor-Solvent-Coal-Liquefaction process (EDS) developed by Exxon. Rehydrogenation of the hydrogen-donating solvent is achieved in a special process stage through a fixed-bed catalyst (Figure 3.23). 

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