METHOD OF ALKYLATING ISOBUTANE IN THREE-PHASE REACTOR WITH FIXED LAYER OF CATALYST Russian patent published in 2017 - IPC C07C2/58 C07C9/00 B01J8/06 

FIELD: chemistry.

SUBSTANCE: butylenes are fed to each catalyst bed, and isobutane taken in excess to the top of the reactor, an alkylation reaction is carried out, the unreacted isobutane is separated and recycled, and the resulting alkyl benzene is recovered. The temperature and pressure are chosen so that the isobutane vapour is in a saturated state, and additional evaporation of the liquid in the reactor under the action of the reaction heat provides isothermal conditions for the alkylation process. The liquid flows freely without bubbling under the action of gravity at a space velocity of not more than W_max, equal to W_max=0.787D²[ε(1-ε_g)]{[ρ_f+ε_g/(1-ε_g)ρ_g]U_max}/ρ_f, and not less than W_min, equal to W_min=0.787D²[ε(1-ε_g)]{[ρ_f+ε_g/(1-ε_g)ρ_g]U_min}/ρ_f, where D is the cross section of the catalyst bed, m, ε - porosity of the catalyst bed, ε_g - the vapour content in the reactor under the reaction conditions, ρ_f - the liquid density at the reactor inlet, kg/m³, ρ_g - the vapour density in the reactor under the reaction conditions, kg/m³, - is the maximum linear velocity of the freely flowing fluid U_max, m/s, calculated from the system of equations , , where H is the height of the catalyst bed, m, g is the acceleration due to the gravity, m/s², Δp_lost - the lost pressure, Pa, d_p - the average particle diameter of the catalyst, m, μ - the fluid viscosity, Pa/s. The minimum linear velocity of the freely flowing fluid U_min, m/s is equal to , where Ga is Galileo's criterion defined by the formula: , μ - the dynamic viscosity of the liquid, Pa/s, ρ_f - the density, g/m³; d_p - the average particle diameter of the catalyst, m.

EFFECT: increasing the process stability while maintaining high catalyst activity for a long time.

1 dwg, 1 tbl, 7 dwg