Technical development of the DHD process

Technical Report · Thu Oct 15 04:00:00 EDT 1942

OSTI ID:5153568

Donath, E; Simon, W; Nonnenmacher, H

The purpose of the DHD process was to produce aromatics-enriched fuels from any sort of gasoline. It consisted of dehydrogenation and cyclization of naphthenes and paraffinic hydrocarbons to aromatics. The reaction was carried out at a hydrogen pressure of 5 to 30 atm, a total pressure of 10 to 50 atm, and temperatures of about 500/sup 0/C. Although the presence of hydrogen under pressure tended to interfere with dehydrogenation reactions, it was necessary in order to hold down very undesirable side reactions such as coke formation and thereby prolong the time during which the reaction could be maintained. Nevertheless, after about each 100 hours of operation, the catalyst had to be regenerated for about 25 hours (or 1/4 of the operating time) by burning off the buildup, using a mixture of air and inert gas. In contrast to hydrogenation, the DHD process was endothermic. Thus, in order to allow the reaction to continue far enough without having to heat the mixture excessively at the beginning, the process was carried out in a succession of 4 to 6 ovens (total value about 50m/sup 3/) with intermediate tube preheaters before each oven in the sequence. The last oven in the sequence was held at lower temperatures, about 300/sup 0/, and acted as a refining step for the gasoline produced earlier in the process. In actual practice, the beginning material to be processed was distilled into two fractions, with the cut-off point being about 90/sup 0/C. The heavier fraction was then processed by DHD and the resulting gasoline was recombined with the other fraction which was not processed. This article also discussed the similar process called the HF process applied to petroleum products. 2 graphs, 2 diagrams, 3 tables.

• Research Organization: I.G. Farbenindustrie, Ludwigshafen (Germany)
• OSTI ID: 5153568
• Report Number(s): TOM-138-141-148
• Country of Publication: United States
• Language: German

Related Subjects

01 COAL, LIGNITE, AND PEAT
010403* -- Coal & Coal Products-- Hydrogenation-- (-1987)
02 PETROLEUM
020400 -- Petroleum-- Processing
ALKANES
ANTIKNOCK RATINGS
AROMATICS
AROMATIZATION
AVIATION FUELS
CATALYSTS
CHEMICAL REACTIONS
CHEMICAL REACTORS
COAL LIQUEFACTION
COMPARATIVE EVALUATIONS
CONTAINERS
CRYOGENIC FLUIDS
CYCLOALKANES
DEHYDROGENATION
DIAGRAMS
ELEMENTS
ENTHALPY
FLUIDS
FOULING
FUELS
GASOLINE
HEATERS
HIGH TEMPERATURE
HYDROCARBONS
HYDROGEN
INFORMATION
LIQUEFACTION
MEDIUM PRESSURE
NONMETALS
ORGANIC COMPOUNDS
PERFORMANCE TESTING
PETROLEUM PRODUCTS
PHYSICAL PROPERTIES
PRESSURE VESSELS
PRODUCTION
REACTION HEAT
REGENERATION
SYNTHETIC FUELS
TABLES
TESTING
THERMODYNAMIC PROPERTIES