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condensation we explain the "strange" dependences ob- served in this study or described in the literature. We have simulated jet fuel dearomatization taking in-.
React.

Kinet.

Catal.

Lett.,

Vol.

53, No.

2, 253-259

(1994)

RKCL2507

CATALYTIC

REACTIONS

ACCOMPANIED

I. FORMULATION N.M.

Ostrovskii,

N.M.

Omsk Department

of Boreskov

phase

significantly small ones

We have

Capillary pore

644040,

Russia

in particular

conditions

motor

appear

Regarding

the "strange"

study or described

to differ and

capillary

dependences

ob-

taking

in-

is widely used for testing

the

condensation

condensation structure

fuel

in the literature.

jet fuel dearomatization

capillary

gas-

(filled with gas)

liquid).

we explain

simulated

to account

catalyst

Reaction

(filled with

in this

of Catalysis

found to accompany

in large pores

condensation served

was

reactions,

hydrotreatment.

Duplyakin

February 18, 1994 March 28, 1994

condensation

catalytic

and V.K.

Institute

54, Omsk,

Received Accepted

CONDENSATION.

OF THE PROBLEMS

Bukhavtsova

Neftezavodskaya

Capillary

BY CAPILLARY

as well.

based on the Kelvin

equation:

in P/Ps = OVm/rmRT where

P, Ps - are the partial

pressure

of a condensing

face tension; cus radius

respectively;

vapor

a is the sur-

r m is the liquid menis-

in this work show that capillary

at some large scale processes

and pressures.

is gaseous

and saturated

T is the temperature.

made

takes place

temperatures mixture

component,

V m is the molar volume;

in a pore;

The estimates densation

pressure

(vapors),

At reactor

inlet and outlet

but inside

the catalyst

Akad4miai

con-

under high the

pellets

Kiad6,

Budapest

OSTROVSKII et al.: CAPILLARY CONDENSATION b o t h gas-phase actions

reactions

(in small pores)

Obviously,

(in large pores)

and liquid-phase

re-

occur.

this situation differs

significantly

in the model of partially wetted pellets

from that

[1,2] when the reagents

are both gaseous and liquid. Here, only a part of external surface is dry. PROBABILITY OF CAPILLARY CONDENSATION The estimates resulting that capillary condensation

from the Kelvin equation indicate is possible

in some refinery pro-

cesses. In h y d r o d e s u l f u r i z a t i o n

(HDS) and hydrodearomatization

(HDA) of jet fuels on Ni-Mo/AI203

all the pores less than 70

in radius are filled with liquid heavy kerosines.

This fraction

(boiling temperature

(TB = 140-

240 ~

T B = 220-240

and its partial pressure

densation occurs at 300

~

perature increases to 310 ~ filled with liquid. to 290 ~

C) attains

10%

is Phf = 4.2 atm. The con-

(Fig. i). When

the operation tem-

only the pores with r < 35 ~ are

On the other hand, a temperature

leads to blocking of all mesopores

The pores with r