Device and method for preparing para-xylene and co-producing light olefins from methanol and/or dimethyl ether and benzene

#The present application relates to a device and a production method for producing para-xylene (PX) and co-producing light olefins, and is particularly suitable for a fluidized bed device and a production method for preparing para-xylene and co-producing light olefins by the alkylation of methanol and/or dimethyl ether and benzene, which belongs to the field of chemistry and chemical industry.

#Para-xylene (PX) is one of the basic organic raw materials in the petrochemical industry, which has a wide range of applications in chemical fiber, synthetic resins, pesticides, pharmaceuticals and polymer materials. At present, the production of para-xylene mainly uses toluene, C9 aromatics and mixed xylene as raw materials, and para-xylene is obtained by disproportionation, isomerization, adsorption separation or cryogenic separation. Since the para-xylene content in the product is controlled by thermodynamics, para-xylene only accounts for ˜24% of the C8 mixed aromatics, and the material circulation processing amount is large during the process, and the equipment is large and the operation cost is high. In particular, the three isomers of xylene have small differences in boiling points, and it is difficult to obtain high-purity para-xylene by conventional distillation techniques, and an expensive adsorption separation process must be employed. In recent years, many patents, domestic and abroad, have disclosed a new route for the production of para-xylene. The alkylation technology of methanol and/or dimethyl ether and benzene is a new way to produce para-xylene with high selectivity, which has been highly valued and paid great attention by the industry.

#Light olefins, namely ethylene, propylene and butene, are two basic petrochemical feedstocks that are increasingly in demand Ethylene and propylene are mainly produced from naphtha, depending on the petroleum route. In recent years, the non-petroleum route to produce ethylene and propylene has received more and more attention, especially the process route of the methanol conversion to light olefins (MTO), which is an important way to achieve petroleum substitution strategy, reduce and alleviate our demand and dependence for petroleum.

#FIG. 1 is a schematic diagram of a device for producing para-xylene and co-producing light olefins from methanol and/or dimethyl ether and benzene according to an embodiment of the present application.

#The reference numerals in the figures are listed as follows:

#1—fast fluidized bed reactor; 2—reactor shell; 3—reactor feed distributors (3-1˜3-n); 4—reactor gas-solid separator; 5—reactor gas-solid separator; 6—reactor heat extractor; 7—product gas outlet; 8—reactor stripper; 9—reactor stripping gas inlet; 10—inclined spent catalyst pipe; 11—spent catalyst sliding valve; 12—spent catalyst lift pipe; 13—spent catalyst lifting gas inlet; 14—fluidized bed regenerator; 15—regenerator shell; 16—regenerator feed distributor; 17—regenerator gas-solid separator; 18—regenerator heat extractor; 19—flue gas outlet; 20—regenerator stripper; 21—regenerator stripping gas inlet; 22—inclined regenerated catalyst pipe; 23—regenerated catalyst sliding valve; 24—regenerated catalyst lift pipe; 25—regenerated catalyst lifting gas inlet.

#The present application will be described in detail below with reference to the embodiments, but the application is not limited to these embodiments.

#Unless otherwise specified, the raw materials and catalysts in the embodiments of the present application are commercially available.

#As an embodiment of the present application, a schematic diagram of a device for producing para-xylene and co-producing light olefins from methanol and/or dimethyl ether and benzene is shown in FIG. 1. The device comprises the fast fluidized bed reactor 1, which comprises a reactor shell 2, n reactor feed distributors 3-1 to 3-n (the distributor between 3-1 and 3-n in FIG. 1 takes 3-i as an example), a reactor gas-solid separator 4, a reactor gas-solid separator 5, a reactor heat extractor 6, a product gas outlet 7 and a reactor stripper 8, wherein the lower part of the fast fluidized bed reactor 1 is a reaction zone, the upper part of the fast fluidized bed reactor 1 is a dilute phase zone, the n reactor feed distributors of 3-1 to 3-n are arranged from bottom to top in the reaction zone, 2≤n≤11, the reactor heat extractor 6 is disposed in the reaction zone or outside the reactor shell 2, the reactor gas-solid separator 4 and the reactor gas-solid separator 5 are placed in the dilute phase zone or outside the reactor shell 2, the inlet of the reactor gas-solid separator 4 is connected to a regenerated catalyst lift pipe 24, the catalyst outlet of the reactor gas-solid separator 4 is located at the bottom of the dilute phase zone, the gas outlet of the reactor gas-solid separator 4 is located in the dilute phase zone, the inlet of the reactor gas-solid separator 5 is located in the dilute phase zone, the catalyst outlet of the reactor gas-solid separator 5 is located in the reaction zone, the gas outlet of the reactor gas-solid separator 5 is connected to the product gas outlet 7, and the inlet of the reactor stripper 8 is in the reaction zone of the fast fluidized bed reactor 1, with the horizontal height higher than that of the first reactor distributor.