Processes for converting aromatic hydrocarbons using passivated reactor
AssigneeExxonMobil Chemical Patents Inc.
InventorsSeth M. Washburn, Hsu Chiang, Umar Aslam, Wenyih Frank Lai, Doron Levin, Tan-Jen Chen
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Abstract
This disclosure provides improved processes for converting aromatic hydrocarbons, such as benzene/toluene, alkylation, transalkylation, or isomerization. In an embodiment, a process comprises utilizing a passivated reactor to reduce deactivation of a molecular sieve catalyst. Additional measures such as the use of an auxiliary catalyst and/or an elevated reactor pressure may be used to further reduce deactivation of the molecular sieve catalyst.
Claims23
A process for converting aromatic hydrocarbons, the process comprising:
- (I) providing a passivated reactor;
- (II) providing a conversion catalyst system in the passivated reactor, the conversion catalyst system comprising a molecular sieve catalyst;
- (III) feeding a feed comprising aromatic hydrocarbons into the passivated reactor;
- and
- (IV) contacting the feed with the conversion catalyst system under conversion conditions to produce a conversion product mixture effluent,
- wherein the step (I) comprises:
- (Ia) providing an unpassivated reactor;
- (Ib) passivating the unpassivated reactor to obtain the passivated reactor by methods of passivating internal surface of the unpassivated reactor comprising the following:
- (Ib.1) forming a layer of a glass material on the internal surface of the unpassivated reactor;
- wherein in the step (Ib.1), the glass material is selected from borosilicate glass, aluminosilicate glass, or a combination thereof and the step (Ib.1) comprises coating the internal surface of the unpassivated reactor with particles of the glass material and heating the unpassivated reactor to a temperature ≥600° C.
A process for converting benzene and/or toluene;
- the process comprising:
- (I) providing a passivated methylation reactor;
- (II) providing a fixed bed of a methylation catalyst system in the passivated methylation reactor, wherein the methylation catalyst system comprises a zeolite;
- wherein the zeolite comprises a MWW framework type zeolite, and the methylation catalyst system further comprises an auxiliary catalyst physically mixed with the zeolite, and wherein the auxiliary catalyst comprises an oxide of one or more of the lanthanide series elements;
- (III) feeding a feed comprising an aromatic hydrocarbon and a methylating agent into the passivated methylation reactor, wherein the aromatic hydrocarbon is benzene and/or toluene, and the methylating agent is methanol and/or dimethyl ether;
- and
- (IV) contacting the feed with the methylation catalyst system under conversion conditions effective to produce a conversion product mixture effluent exiting the passivated methylation reactor, wherein the conversion conditions comprise a temperature ranging from 200 to 500° C., and the conversion product mixture effluent comprises methanol, dimethyl ether, and xylenes.
Dependencies are inferred from the claim text.