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higher compared to the traditional y-Al203 and SiO 2 supported systems. The effect of surface area of the support and of the catalyst composition on their cata-.
React. Kinet. Catal. Lett., Vol. 36, No. 1, 65-70 /1988)

CARBON-SUPPORTED

SULFIDE BIMETALLIC

CATALYSTS

FOR HYDROr

DESULFURIZATION [Yu.I. Yermakov[ , A.N. M.S. Institute All-Union

Startsev,

Tsekhanovich

Shkuropat,

and V.F.

of Catalysis,

Research

S.A.

Institute

G.V.

Plaksin,

Surovikin

Novosibirsk

630090,

USSR

of Technical

Carbon,

Omsk,

USSR

Received December 4, 1986 Accepted April 9, 1987

It has been e s t a b l i s h e d ported

sulfide Ni-Mo,

higher c o m p a r e d supported

that the activity of c a r b o n - s u p -

N i - W and Co-Mo catalysts

to the traditional y-Al203

systems.

~OKa3aHO~

T@nb C y ~ b ~ H ~ H ~ X Ni-Mo,

HOBepXHOCTH

A traditional drodemetallization catalysts

to similar

[2-6].

BnH~HHe

HOCHTenH H COCTaBa K a T a n H 3 a T O p O B

support of c a t a l y s ~ for h y d r o r e f i n i n g is y-Al203.

For recent years,

sulfide

systems on u

catalysts

however,

into the c o m p o s i t i o n

supports

of the t e c h n o l o g y

permits

and hythese

[i-6].

The

can be higher

[4-6], because most of of the active

It has been noted p r e v i o u s l y

cation of carbon fication

H3yqeHO

cy-

HaHeceH-

have also been p r e p a r e d on carbon supports

the cobalt enter phase"

CHCTeM,

HOCH-

CBOHCTBa.

a c t i v i t y of c a r b o n - s u p p o r t e d compared

Tpa~H~HOHH~X

H OKHCb anmMHHH~.

Ha HX K a T a ~ H T H q e C K H e

Ha y F H e p o ~ H ~

N i - W H Co-Mo K a T a H H 3 a T 0 p O B

B~me aKTHBHOCTH

HMX Ha CHnHKaPenb y~enbHo~

on their cata-

has been studied.

qTO aKTHBHOCTb H a H e C e H H ~ X

~eCTBeHHO

and SiO 2

The effect of surface area of the

support and of the c a t a l y s t c o m p o s i t i o n lytic p r o p e r t i e s

is much

"Co-Mo-S

[5] that the appli-

to achieve

to extract metals

the utmost simplifrom e x h a u s t e d

Akad~miai Kiadd, Budapest

YERMAKOV et al. : H Y D R O D E S U L F U R I Z A T I O N

catalysts

for hydrorefining

ports.

But carbon

hardly

compete

described

supports

of activated

charcoal

due to their

low mechanical

of narrow pores.

Material

Besides,

type Sibunit whose

previously

Here we present pare sulfide

out their

with oxides

and the high portion ash content.

by simply burning

[7], is free

the results

catalysts

type,

supcan strength

they have high

properties

have been

from these disadvantages.

of applying

for thiophene

this material

to pre-

hydrogenolysis.

EXPERIMENTAL Carbon material used as a support and Si02-supported spectively,

were

catalysts

were prepared

Catalysts aqueous

commercial

of W(Mo)

analytical

(NH4)6Mo7024.4H20.

and treated

with

a trap at T = -70 ~ sulfurization without

the model

in Table

reaction

and T = 300 ~

RESULTS

Chemical

Parent

sealed

i. Catalyst

of thiophene

Co(NO3)2"6H20;

calcined

were

products

vessels

composition

activities

circula-

degassed

in reaction

samples

in air at 400

out sulfurization

Chemical

compounds

catalyst

for 1 h in a static samples

with

and stored

of catalyst

were compared

hydrogenolysis

in

at the

is in

at PH2 = 2 MPa

[8].

compositions

in different

with the atomic

ratio

and activities

carriers

component

activity

[8] is only

(M 1 = Ni, Co;

(per 1 g) activity

is almost maximum, sulfide

1.5 -2 times

are listed catalysts as highs

catalysts

and Carbon)

h = M I / M 1 + M 2) = 0.2 - 0.3

of Si02-supported

lic origin

of sulfide

(SiO2, 7-A1203

M 2 = Mo, W) at which the specific

66

re-

AND DISCUSSION

supported

active

salts.

impregnation,

(120 ~

freezing

with air.

impregnation

grade Ni(NO3)2"6H20; After

Sulfurized

temperature,

contact

represented

by one-step

in H2S at 400 ~

tion installation

7-A1203-

with SBE T = 200 and 240 m2/g,

and Ni(Co)

were dried by IR irradiation ~

traditional

[8].

were prepared

solutions

WO 3 and

type Sibunit with SBE T = 17-550 m2/g was

[7]. For comparison,

of the

in Table

i. The

of organometalas that of the

YERMAKOV et al. : HYDRODESULFURIZATION

Table Composition

and c a t a l y t i c

Composition of catalysts

properties

of b i m e t a l l i c

SBET f o r s u p p o r t s

catalysts.

No.

1

Support

sulfide

= 200-240 m2/g

Metal concentration (wt.%) Co or Ni

Activity at 300 UC mol thioph. g-at(Ml+M2)xSx

Mo or W

xl04 1

Ni-W

Sibunit

0.8

4.2

ii0

2

Ni-W

Sibunit

1.0

6.0

83

3

Ni-W

Sibunit

1.2

9.0

74

4

Ni-W

SiO 2

1.0

6.4

50

5

Ni-W

AI203

1.2

8.0

48

6

Ni-Mo

Sibunit

0.6

4.0

116

7

Ni-Mo

Sibunit

1.5

i0.0

92

8

Ni-Mo

SiO 2

0.8

2.3

30

9

Ni-Mo

AI203

1.8

6.0

30

10

Co-Mo

Sibunit

I.i

8.0

60

corresponding This

catalysts

fact can be a s c r i b e d

ported lysts

catalysts. supported

on c a r b o n

decrease

metals

increasing

with

is due to the rising

We b e l i e v e of the c a t a l y s t used

evidence

the

being

by i m p r e g n a t i o n

metal

in the m e a n

same r e a s o n

activity

coarse surface

particles

are c h a r a c t e r i z e d I g-at.

accounts

having

of m i x e d

is, a p p a r e n t l y ,

of s u p p o r t e d

Apparently,

size of s u l f i d e

this

particles

(Fig.

for the d e p e n d e n c e area of c a r b o n

material

I). The m e t a l

concen-

the c h a r a c t e r i s t i c

that on a c a r r i e r

the cata-

of metals.

on the surface

preparation

the same,

per

of c a r b o n - s u p -

systems,

concentration.

concentration

for the c a t a l y s t

tration

more

the

by i m p r e g n a t i o n .

organometallic

in the a c t i v i t y

increase

surface

on c a r b o n

to the high d i s p e r s i t y

But u n l i k e

by a s l i g h t

with

supported

curve

a low s u r f a c e

sulfides,

~nsufficient

since

is likely area

there

to form

in this case

to e n s u r e

the

"mono67

Y E R M A K O V et al. : HYDRODESULFURIZATION

~o so

p

~-, 4o

>

200

Fig.

i.

Ac~vity

400 600 SurfQce o r e a , m 2 9-1

of N i - M o

area of c a r b o n centration

catalysts

carriers

versus

the

at a c o n s t a n t

in the c a t a l y s t s

surface metal

(4% Mo and

O

con-

1.5% Ni)

O

x

800

z

120 ~ "6

0

-~ E

o-'

"6

0