Aromatization of straight-chain aliphatic hydrocarbons from the Fischer--Tropsch synthesis

Technical Report ·

OSTI ID:6565892

Rottig,

The aromatization process described here was applied to normal paraffins of about 6 to 8 carbon atoms in order to cyclize them to aromatics of the same number of carbon atoms. The change of structure increased the octane numbers of the compounds by up to 50 units and increased their density considerably. In addition to gasoline improvement, the process could also be used to produce pure aromatic compounds for other purposes, such as for use in explosives, pharmaceuticals, plastics, synthetic resins and laquers, etc. This report gave a discussion of the development of various kinds of catalysts for the process, including aluminum oxide-chromium oxide gels and calcined magnesite-chromium oxide catalysts. After a certain period of operation, the catalyst became clogged with high-molecular-weight molecules and had to be regenerated by burning off the deposited material. But in that process, some of the catalyst became oxidized and had to be reduced again by passing hydrogen over it. Thus the catalyst usage and regeneration made up a three-stage process, so the Ruhrchemie ran the process with three identical oven systems, one in each mode at a given time. Since aromatization was an endothermic reaction, the heat built up in the catalyst by the oxidation and reduction stages of regeneration was balanced against the heat absorbed by the reaction. Thus the three-stage cycle was run on a plan of changing modes in each oven about every half hour, with short periods of rinsing with gases between modes. The reaction was carried out at 400/sup 0/ to 500/sup 0/C but at atmospheric pressure; the regeneration was carried out at 450/sup 0/C and about 3 to 4 atm pressure, and the reduction at about 0.3 to 0.4 atm pressure. If pure aromatics were to be produced, the gasoline from the reactors would have to be put through subsequent fractionating distillations, and/or the starting material would have to be fractionated before being processed. 1 diagram.

• Research Organization: Ruhrchemie, A.G., Oberhausen (Germany, F.R.)
• OSTI ID: 6565892
• Report Number(s): TOM-138-395-409
• Country of Publication: United States
• Language: German

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
010405 -- Coal
Lignite
& Peat-- Hydrogenation & Liquefaction
090121* -- Hydrocarbon Fuels-- Chemical Synthesis-- (1976-1989)
10 SYNTHETIC FUELS
ALKALINE EARTH METAL COMPOUNDS
ALKANES
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
ANTIKNOCK RATINGS
AROMATICS
AROMATIZATION
CARBON COMPOUNDS
CARBONATES
CATALYSTS
CATALYTIC EFFECTS
CHALCOGENIDES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CHEMICAL REACTORS
CHROMIUM COMPOUNDS
CHROMIUM OXIDES
COAL GASIFICATION
CRYOGENIC FLUIDS
DATA
DATA COMPILATION
DENSITY
DEPOSITION
DIAGRAMS
DISTILLATION
ELEMENTS
ENTHALPY
EVALUATION
FISCHER-TROPSCH SYNTHESIS
FLUIDS
FUELS
GASIFICATION
GASOLINE
HIGH TEMPERATURE
HYDROCARBONS
HYDROGEN
INFORMATION
INTERFERING ELEMENTS
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MEDIUM PRESSURE
NONMETALS
NORMAL-MODE ANALYSIS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PETROLEUM PRODUCTS
PHYSICAL PROPERTIES
PRODUCTION
REACTION HEAT
REDUCTION
REGENERATION
SEPARATION PROCESSES
SYNTHETIC FUELS
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS