Method for passivating the inner surface by deposition of a ceramic coating of an apparatus subject to coking, apparatus prepared thereby, and method of utilizing apparatus prepared thereby
AssigneesIstituto Guido Donegani S.p.A., Enichem S.p.A.
InventorsTerence J. Clark, Michael J. Hanagan, Richard W. Cruse, Veronika A. Szalai, Stephen J. Rohman, Robert M. Mininni
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Abstract
In order to reduce the rate of coke formation during the industrial pyrolysis of hydrocarbons, the interior surface of the reactor tubes are coated with a thin layer of a ceramic material, said layer being deposited by thermal decomposition of a non-oxygen containing silicon organometallic precursor in the vapor phase, in an inert or reducing gas atmosphere in order to minimize the formation of oxide ceramics.
Claims13
A method for passivating the inner surface of a metallic reactor tube which is used in steam or steamless hydrocarbon pyrolysis, comprising decomposing at 700.degree. C.-900.degree. C. a non-oxygen containing silicon containing precursor selected from the group consisting of hexamethyldisilazane, tetramethylsilane, (diethylamino)trimethylsilane, (isopropylamino)trimethylsilane, (dimethylamino)trimethylsilane, heptamethyldisilazane, bis(isopropylamino)dimethylsilane, hexamethyldisilane, tetramethyldisilazane, (diethylamino)triethylsilane, tetrakis(dimethylamino)silane, bis(dimethylamino)methylsilane, (dimethylamino)triethylsilane, trimethylsilane, (dimethylamino)benzyldimethylsilane, (dimethylamino)phenylmethylsilane, (2-picolylamino)trimethylsilane, tris(isopropylamino)methylsilane, dimethylsilane, bis(diethylamino)methylsilane, (dimethylamino)benzylmethylsilane, butylmethylphenylsilane, (diisopropylamino)methylchlorosilane, octamethyltrisilazane, bis(dimethylamino)phenylsilane, benzylmethylchlorosilane, triisopropylsilane, tris(dimethylamino)methylsilane, diethylmethylsilane, triethylsilane, bis(dimethylamino)ethylsilane, hexamethyltrisilazane, and (dimethylamino)dimethylsilane, in the vapor phase, in an inert or reducing gas atmosphere in said tube to form a thin layer of 1 to 20 .mu.m of a ceramic material on a surface of said reactor tube.
Dependencies are inferred from the claim text.