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Activity of heterogeneous catalysts in liquid-phase oxidation of tetralin
A . N . KAM~-EVA et a/.
86
18, F. I, NOVAK, A. N. BASHKIROV. YU. A. TALYZENKOV and A. N. BASHgIROV Dokl. AN SSSR 214, No. 6, 1346, 1974 19. AI. A. PETROV, K. M. SOKOVA. V. V. KAMZOLKIN and A. N. B A S ~ I R O V , /)old. AN SSSR 203, 113, 1972 20. H. NOZAKI and R. NOYORI, J. Organ. Chem. 30, 1652, 1965 21. M. ROSENBLUM, J. Amer. Chem. Soe. 79, 3179, 1957 22. V. S. JOHNSON, R. D. SHENNAN and R. A. REED, Organicheskiye reaktivy dlya organieheskogo analiza (Organic Reagents for Organic Analysis) Izd. inostr, lit. Moscow, 1948 23. L. I. ZAKHARKIN and V. V. KORNEVA, Dokl. AN SSSR 132, 1078, 1960
ACTIVITY OF HETEROGENEOUS CATALYSTS IN LIQUID-PHASE OXIDATION OF TETRALIN* A. N. ~ v x ,
V. I. ZAKWAROVA, A. V. ART~MOV, V. A. SET,~ZNEV and YE. N. ~ARTYNOVA
D. I. Mendeleyev Chemico-Technological Institute, Moscow
(Received 9 September 1975) HETEROGENEOUS c a t a l y s t s in liquid-phase o x i d a t i o n of h y d r o c a r b o n s h a v e several a d v a n t a g e s o v e r h o m o g e n e o u s catalysts. U s i n g h e t e r o g e n e o u s c a t a lysts t h e r a t e o f i n t e r m e d i a t e p r o d u c t f o r m a t i o n a n d process selectivity increase. This p a p e r is concerned w i t h t h e s t u d y of t h e c o m p a r a t i v e c a t a l y t i c a c t i v i t y a n d s e l e c t i v i t y o f v a r i o u s h e t e r o g e n e o u s c a t a l y s t s m a d e f r o m activ a t e d charcoal a n d c a r b o n b l a c k w i t h m e t a l ions o f v a r i a b l e v a l e n c y applied on t h e i r surfaces: m a n g a n e s e , cobalt, iron a n d nickel in liquid-phase o x i d a t i o n o f tetralin. B A U , AG-3, S K T , K A D a n d A G N a c t i v a t e d charcoals a n d c h a n n e l g a s b l a c k w i t h a specific surface o f 150 m2/g (KS-150), channel gas b l a c k w i t h a specific surface of 300 m~/g (KS-300) a n d PM-70 c a r b o n b l a c k were used as carriers. TABLE 1. COMPARISON
OF CATALYTIC A C T I V I T I E S OF VARIOUS
METAL CATIONS A P P L I E D ON K S - 1 5 0
W X 10 4,
Cation
mole/1. • see
Cation
W × 10', mole/1. • see
CoS+
0.005 5"950 2.610
Fe z+ Ni *+
0.373 0.012
MnS+
* IWeftekhimiya 16, No. 3, 452-456, 1976.
Activity of heterogeneous catalysts
87
Tetralin was oxidized in gasomctric and diffuser equipment [1, 2] at temperatures of 50 to 140 ° in the kinetic range. Reaction products were analysed chromatographically [2] and tetralin hydroperoxide content was determined b y iodometric titration. Before the experiments the initial tetralin was purified b y methods previously described [3]. The catalyst was prepared b y the following method. Initial activated charcoal and carbon black samples were carefully washed with hydrochloric acid to remove mineral impurities and then according to a previous description [4], acid centres were formed on the surface, which were neutralized with NaOH, followed b y l~a + ion exchange to a corresponding metal of variable valency. Exchange was carried out from nitrate solution. The amount of ionexchange metal of variable valency was 2.04-0.78~/o wt. in the catalysts prepared. T A B L E 2. COMI~ARISON OF CATALYTIC ACTIVITIES OF C o S+ AND C o s+ CATIONS O:bT DIFFEREI~-T CARRIERS
Carrier KS-150 KS-300 PM-70 SKT
W × 104, mole/1., see C o 3+
C o S+
9.95
4.20 4.73
6.70 3.57 1.07
1.49
1.44
W × 104, mole/1..see
Carrier KAD AGN BAU AG-3
Coa+
Co~+
1-32 1.34 2.17
0.96 0.90 2.09
--
0.96
The first stage of the study involved the selection of the most active cation applied on a carrier containing carbon. KS-150 carbon black was selected as carrier. Oxidation was carried out at a temperature of 67 °. The catalyst was used in a proportion of 25 g/1. reaction mixture. Catalyst activity was evaluated from the rate of oxygen absorption (Table 1). Experimental results thus suggest that the use of a heterogeneous catal y s t - - a carbon carrier containing an ion-exchange metal of variable valency on the surface accelerates tetralin oxidation, in comparison with the noncatalytic process and the effect of catalyst on the process is determined b y the t y p e of ion-exchange cation. TABLE 3.
E a c t VALUES I N TETRALIN OXIDATION I N THE PRESENCE OF VARIOUS CATALYSTS
Catalyst Co2+/SiOs Co (St)s
Eact,
kcal/mole 11-0 13.5
Eact
Eact,
Catalyst
keal/mole
Catalyst
kcal/mole
Co'+/BAU Co'+/KS-150
11.0
Co,O4
11"0
9.7
The effect of the type of initial carrier containing carbon on liquid-phase oxidation of tetralin was examined at a temperature of 70 ° and 25 g catalyst was used for each 1. reaction mixture. Cobalt being the most active (Table 1) was selected as ion-exchange cation. Results concerning the rate of oxygen
88
A.N.
K_~,~
et al.
absorption in tetralin oxidation with catalysts using various carriers containing carbon, are shown in Table 2. Using a Co 3+ ion on initial carriers containing carbon does not markedly alter the order of activity described. However, comparison of the catalytic activity of catalysts with Co S+ and Co 3+ ions applied on the surface of the same carrier shows t h a t the initial rate of oxidation of tetralin in t]ae presence of catalysts with Co s+ increases considerably (Table 2). ~ , ml/m/.
% wt
0"2
6'
!
~"'×
Y O'Oa
007
CO27KS-/5~q
FIG. 1
30
80
IEO
210
T, ,-~in
FIG. 2
FIO. 1. Relation botween the rate of oxygen absorption in totralin oxidation a n d the a m o u n t of CoI+/KS-150 catalyst. Temperature 65 °, volume of reaction mixture 2 ml. FIG. 2. Kinetic curves of formation of totral-l-one (1-3) a n d t e t r a l - l - o l (1'-3') in tetralin oxidation. 1 - - n o n . c a t a l y t i c ; 2--CoI+/KS-150; 3--Co*+/KS-150. I n Figs. 2, 3 temperature 140°C; a m o u n t of catalyst 0.5 g, volume of reaction mixture 100 ml.
Thus, results of oxygen absorption at early stages of oxidation from the heterogeneous catalysts studied indicate that Co2÷/KS-150 and Co8+/KS-150 are the most active. The dependence of the rate of oxygen absorption on the a m o u n t of Co2+/KS-150 catalyst is shown in Fig. 1. Thus relation shows the maximum with 32.5 g catalyst/1, reaction mixture. The extremal nature of the curve confirms the assumption [5] that heterogeneous catalysts in small proportions are initiators, whereas in proportions exceeding the "critical", t h e y inhibit the process. It was established t h a t the reaction is of first order in relation to the catalyst. When studying the effect of the concentration of tetralin, the initial hydrocarbon, on the rate of oxidation it was found that the reaction in relation to hydrocarbon was of the 2nd order. The dependence of the rate of oxygen absorption on temperature was e x a m i n e d in the temperature range of 40-89 ° and 32.5 g catalyst was used per I. reaction mixture. The apparent activation energy of the reaction was determined from results and found to be 9.7 kcal/mole. The Eact value found was lower than for catalysts previously examined [6] (Table 3).
Activity of heterogeneous catalysts
89
T a b l e 4 shows a t o m i c catalytic activities (ACA) [7] for Co2+/K8-150 catalysts. ACA values for o t h e r catalysts previously e x a m i n e d [6] are given for comparison. ACA values were calculated f r o m the r a t e of o x y g e n absorption. W h e n calculating ACA for C02+/KS-150 t h e entire a m o u n t o f ion-exchange m e t a l in t h e c a t a l y s t was considered• T h e Table shows t h a t the ACA vMue %wt. %w~.
%w~ 15
- 6o
g~ 8~ 2/720
60
IO0 /ZlO ]80 T~rnzn
Fro. 3. Kinetic curves of formation of reaction products in the presence of Coa+/KS-150; 1--tetral-l-one; 2--tetral-l-ol; 3--tetralin hydroperoxide; 4--1-oxy-keto-l,2,3,4-tetrahydronaphthalene; 5--1,1'-ditetralyls; 6--naphtho-l,4-quinone; 7--naphthol-1; 8-tetralin conversions. for a Co2+/KS-150 c a t a l y s t is close to t h e value derived o f t e t r a l i n o x i d a t i o n such as Co~+/SiO~ a n d Co (St)~. I n o r d e r t o e x a m i n e t h e f o r m a t i o n of main p r o d u c t s of h y d r o p e r o x i d e s of tetralin, t e t r a l - l - o n e a n d t e t r a l - l - o l Co2+/KS-150 and Co3+/KS-150, o x i d a t i o n was r e p e a t e d l y TABLE
4 . C O M P A R I S O N OF ATO~¢IIC C A T A L Y T I C A C T I V I T I E S
(ACA) OF
for active catalysts tetralin o x i d a t i o n - in t h e presence of carried out using a DIFFERENT
CATALYSTS
Reaction volume 2 ml
Catalyst
Amount of catalyst, g
Content of Co ion in the catalyst sample,
W × 104, mole/1. • •Sec
ACA x 10~3, mole/1. •sec. ion
% ~t.
Co~+/SiO, Co2+/BAU Co~04 Co(Sth Co*+/KS-150
0.100 0.025 0.100 0.015 0.050
0.50 1.38
1-80 0.40
10.00 2.07
4.80 6.70
1-50
3.60 1.15 1.15 3-10 3-24
diffuser. O x i d a t i o n was carried out at a t e m p e r a t u r e of 140 °. 5 g c a t a l y s t was used per 1. r e a c t i o n m i x t u r e . I t was previously shown t h a t a carrier containing c a r b o n has no m a r k e d effect on t h e yield of main p r o d u c t s of oxidation, corn-
A. ~. KA~NEVA et
9O
al.
pared with non-catalytic oxidation. Using a Co2+/KS-150 and Co3+/KS-150 catalyst changes the type of formation of reaction products (Fig. 2): the rate of formation of tetral-l-one, the intermediate reaction products increases, compared with other heterogeneous systems previously examined (Table 5). TABLE 5. INITIAL :RATEFORMATIONOF TETRAL-I-ONE IN TETRALINOXIDATIONON DIFFERENT CATALYSTS Temperature 140°C
Catalyst
Amount of catalyst, g/1. reaction mixture
Co~+/KS-150
5"00 5"00
Co~+/SiO~
4"99
Co3+/KS- 150
Catalyst
A_mount of catalyst, g/1. reaction mixture
mole/1., see
Co2+/BAU CoNaY 00804
6"00 5"00 6"22
17.96 4.79 9.25
Wo × 105,
mole/1. •see 31.8 24.4 6.20 18"4
Wo × 10 5,
In addition to examining kinetics of formation of main reaction products-tetral-l-one, tetral-l-ol and tetralin hydroperoxide--studies were made of the type and kinetics of formation of by-products of tetralin oxidation in the presence of a Co*+/KS-150 catalyst. Figure 3 shows kinetic curves of the formation of reaction by-products--naphtho-l,4-quinone, naphthol-1, 1-keto4-oxy-l,2,3,4-tetrahydronaphthalene and 1,1'-ditetralyls. For comparison, this figure shows kinetic curves of formation of tetral-l-one, tetral-2-ol and tetralin hydroperoxide. A study of these relations shows that reaction byproducts begin to be formed vigorously 80-90 min after the commencement of the reaction; the sequence of formation of these products is the same as in tetralin oxidation in the presence of a homogeneous catalyst--Co(St)2 [8] and several other heterogeneous catalysts [6]. SUMMARY
l. A s t u d y was made of the catalytic activity of heterogeneous catalysts prepared using variable valency metals and carriers containing carbon in liquid-phase oxidation of tetralin. 2. A cobalt cation applied on the surface of channel black (Ss,= 150 m*/g) has the highest catalytic activity. In the presence of this catalyst highest rates of formation can be obtained for tetral-l-one, the intermediate product. REFERENCES 1. L. N. PISHERSKH, V. I. ZAKHAROVA, N. I. ARTEMOVA and A. I. KAMNEVA,
Tr. Mosk. khim.-tekhnol, in-ta ira. D. I. Mendeleyeva (Proceedings of the D. I. Mendeleyev Chemical Technological Institute, Moscow). 14, 74, 1973
Oxidation of hydrocarbon fuels
91
2. L. N. PISHERSKII, V. I. ZAKHAROVA, V. A. SELEZNEV, L. N. IVLEVA, Yu. V. BENTSIANOV and A. V. ARTEMOV, Tr. Tul'sk. ped.-in-ta, Tula, 5, 1973 3. A. M U K H E R J E E a n d W. F. GRAYDON, J. Phys. Chem. 71, 4232, 1967 4. N. P. BOEHM, Advances in Catalysis, L o n d o n - P a r i s 16, 179, 1966 5. Ya. B. GOROKHOVATSKII, Vtoroi sovetsko-yaponskii seminar 13o katalizu. N o v y y e dostizheniya v katalize (Second Soviet-Japanese Seminar on Catalysis. Progress in Catalysis). Tokyo, 1973 6. A. I. KAMNEVA, V. I. ZAKHAROVA, L. N. PISHERSKII, V. A. SELEZNEV a n d A. V. ARTEMOV, Neftekhimiya 15, 403, 1975 7. G. K. BORESKOV, K i n c t i k a i kataliz 14, 7, 1973 8. M. Ya. GERVITS, K a n d . dis. N.-i. in-t organ, poluproduktov i krasitelei (Post-graduate thesis. Scientific I n s t i t u t e of Organic I n t e r m e d i a t e Products and Dyes). Moscow, 1972
KINETICS OF OXIDATION OF HYDROCARBON FUELS BY DISSOLVED OXYGEN IN CLOSED VOLUME* G. I. K o v ~ E v and YE. T. DF,~ISOV I n s t i t u t e of Chemical Physics, U.S.S.R. A c a d e m y of Sciences
(Received 6 May 1975)
OXIDATIO:N of hydrocarbons is normally studies with continuous oxygen supply to the hydrocarbon oxidized (diffusion oxidation). However, in practice hydrocarbons are often oxidized in closed volume with oxygen deficiency. An example m a y be the oxidation of fuels with oxygen dissolved in fuel systems liberating heat. Products of oxidation formed cause a marked deterioration in operational characteristics of fuel systems. There are no results available in t h e literature concerning kinetic relations of oxidation under these conditions. This study is concerned with kinetics of oxidation of hydrocarbon fuels in closed volume with dissolved oxygen and a comparison with kinetics o f oxidation of fuels in a diffusion system. EXPERIMENTAL
The fractional and approximate chemical composition of the fuels examined is shown in Table 1. Commercial n-hexadecane was used as model hydrocarDon. * Noftokhimiya 16, No. 3, 457-464, 1976.
86
18, F. I, NOVAK, A. N. BASHKIROV. YU. A. TALYZENKOV and A. N. BASHgIROV Dokl. AN SSSR 214, No. 6, 1346, 1974 19. AI. A. PETROV, K. M. SOKOVA. V. V. KAMZOLKIN and A. N. B A S ~ I R O V , /)old. AN SSSR 203, 113, 1972 20. H. NOZAKI and R. NOYORI, J. Organ. Chem. 30, 1652, 1965 21. M. ROSENBLUM, J. Amer. Chem. Soe. 79, 3179, 1957 22. V. S. JOHNSON, R. D. SHENNAN and R. A. REED, Organicheskiye reaktivy dlya organieheskogo analiza (Organic Reagents for Organic Analysis) Izd. inostr, lit. Moscow, 1948 23. L. I. ZAKHARKIN and V. V. KORNEVA, Dokl. AN SSSR 132, 1078, 1960
ACTIVITY OF HETEROGENEOUS CATALYSTS IN LIQUID-PHASE OXIDATION OF TETRALIN* A. N. ~ v x ,
V. I. ZAKWAROVA, A. V. ART~MOV, V. A. SET,~ZNEV and YE. N. ~ARTYNOVA
D. I. Mendeleyev Chemico-Technological Institute, Moscow
(Received 9 September 1975) HETEROGENEOUS c a t a l y s t s in liquid-phase o x i d a t i o n of h y d r o c a r b o n s h a v e several a d v a n t a g e s o v e r h o m o g e n e o u s catalysts. U s i n g h e t e r o g e n e o u s c a t a lysts t h e r a t e o f i n t e r m e d i a t e p r o d u c t f o r m a t i o n a n d process selectivity increase. This p a p e r is concerned w i t h t h e s t u d y of t h e c o m p a r a t i v e c a t a l y t i c a c t i v i t y a n d s e l e c t i v i t y o f v a r i o u s h e t e r o g e n e o u s c a t a l y s t s m a d e f r o m activ a t e d charcoal a n d c a r b o n b l a c k w i t h m e t a l ions o f v a r i a b l e v a l e n c y applied on t h e i r surfaces: m a n g a n e s e , cobalt, iron a n d nickel in liquid-phase o x i d a t i o n o f tetralin. B A U , AG-3, S K T , K A D a n d A G N a c t i v a t e d charcoals a n d c h a n n e l g a s b l a c k w i t h a specific surface o f 150 m2/g (KS-150), channel gas b l a c k w i t h a specific surface of 300 m~/g (KS-300) a n d PM-70 c a r b o n b l a c k were used as carriers. TABLE 1. COMPARISON
OF CATALYTIC A C T I V I T I E S OF VARIOUS
METAL CATIONS A P P L I E D ON K S - 1 5 0
W X 10 4,
Cation
mole/1. • see
Cation
W × 10', mole/1. • see
CoS+
0.005 5"950 2.610
Fe z+ Ni *+
0.373 0.012
MnS+
* IWeftekhimiya 16, No. 3, 452-456, 1976.
Activity of heterogeneous catalysts
87
Tetralin was oxidized in gasomctric and diffuser equipment [1, 2] at temperatures of 50 to 140 ° in the kinetic range. Reaction products were analysed chromatographically [2] and tetralin hydroperoxide content was determined b y iodometric titration. Before the experiments the initial tetralin was purified b y methods previously described [3]. The catalyst was prepared b y the following method. Initial activated charcoal and carbon black samples were carefully washed with hydrochloric acid to remove mineral impurities and then according to a previous description [4], acid centres were formed on the surface, which were neutralized with NaOH, followed b y l~a + ion exchange to a corresponding metal of variable valency. Exchange was carried out from nitrate solution. The amount of ionexchange metal of variable valency was 2.04-0.78~/o wt. in the catalysts prepared. T A B L E 2. COMI~ARISON OF CATALYTIC ACTIVITIES OF C o S+ AND C o s+ CATIONS O:bT DIFFEREI~-T CARRIERS
Carrier KS-150 KS-300 PM-70 SKT
W × 104, mole/1., see C o 3+
C o S+
9.95
4.20 4.73
6.70 3.57 1.07
1.49
1.44
W × 104, mole/1..see
Carrier KAD AGN BAU AG-3
Coa+
Co~+
1-32 1.34 2.17
0.96 0.90 2.09
--
0.96
The first stage of the study involved the selection of the most active cation applied on a carrier containing carbon. KS-150 carbon black was selected as carrier. Oxidation was carried out at a temperature of 67 °. The catalyst was used in a proportion of 25 g/1. reaction mixture. Catalyst activity was evaluated from the rate of oxygen absorption (Table 1). Experimental results thus suggest that the use of a heterogeneous catal y s t - - a carbon carrier containing an ion-exchange metal of variable valency on the surface accelerates tetralin oxidation, in comparison with the noncatalytic process and the effect of catalyst on the process is determined b y the t y p e of ion-exchange cation. TABLE 3.
E a c t VALUES I N TETRALIN OXIDATION I N THE PRESENCE OF VARIOUS CATALYSTS
Catalyst Co2+/SiOs Co (St)s
Eact,
kcal/mole 11-0 13.5
Eact
Eact,
Catalyst
keal/mole
Catalyst
kcal/mole
Co'+/BAU Co'+/KS-150
11.0
Co,O4
11"0
9.7
The effect of the type of initial carrier containing carbon on liquid-phase oxidation of tetralin was examined at a temperature of 70 ° and 25 g catalyst was used for each 1. reaction mixture. Cobalt being the most active (Table 1) was selected as ion-exchange cation. Results concerning the rate of oxygen
88
A.N.
K_~,~
et al.
absorption in tetralin oxidation with catalysts using various carriers containing carbon, are shown in Table 2. Using a Co 3+ ion on initial carriers containing carbon does not markedly alter the order of activity described. However, comparison of the catalytic activity of catalysts with Co S+ and Co 3+ ions applied on the surface of the same carrier shows t h a t the initial rate of oxidation of tetralin in t]ae presence of catalysts with Co s+ increases considerably (Table 2). ~ , ml/m/.
% wt
0"2
6'
!
~"'×
Y O'Oa
007
CO27KS-/5~q
FIG. 1
30
80
IEO
210
T, ,-~in
FIG. 2
FIO. 1. Relation botween the rate of oxygen absorption in totralin oxidation a n d the a m o u n t of CoI+/KS-150 catalyst. Temperature 65 °, volume of reaction mixture 2 ml. FIG. 2. Kinetic curves of formation of totral-l-one (1-3) a n d t e t r a l - l - o l (1'-3') in tetralin oxidation. 1 - - n o n . c a t a l y t i c ; 2--CoI+/KS-150; 3--Co*+/KS-150. I n Figs. 2, 3 temperature 140°C; a m o u n t of catalyst 0.5 g, volume of reaction mixture 100 ml.
Thus, results of oxygen absorption at early stages of oxidation from the heterogeneous catalysts studied indicate that Co2÷/KS-150 and Co8+/KS-150 are the most active. The dependence of the rate of oxygen absorption on the a m o u n t of Co2+/KS-150 catalyst is shown in Fig. 1. Thus relation shows the maximum with 32.5 g catalyst/1, reaction mixture. The extremal nature of the curve confirms the assumption [5] that heterogeneous catalysts in small proportions are initiators, whereas in proportions exceeding the "critical", t h e y inhibit the process. It was established t h a t the reaction is of first order in relation to the catalyst. When studying the effect of the concentration of tetralin, the initial hydrocarbon, on the rate of oxidation it was found that the reaction in relation to hydrocarbon was of the 2nd order. The dependence of the rate of oxygen absorption on temperature was e x a m i n e d in the temperature range of 40-89 ° and 32.5 g catalyst was used per I. reaction mixture. The apparent activation energy of the reaction was determined from results and found to be 9.7 kcal/mole. The Eact value found was lower than for catalysts previously examined [6] (Table 3).
Activity of heterogeneous catalysts
89
T a b l e 4 shows a t o m i c catalytic activities (ACA) [7] for Co2+/K8-150 catalysts. ACA values for o t h e r catalysts previously e x a m i n e d [6] are given for comparison. ACA values were calculated f r o m the r a t e of o x y g e n absorption. W h e n calculating ACA for C02+/KS-150 t h e entire a m o u n t o f ion-exchange m e t a l in t h e c a t a l y s t was considered• T h e Table shows t h a t the ACA vMue %wt. %w~.
%w~ 15
- 6o
g~ 8~ 2/720
60
IO0 /ZlO ]80 T~rnzn
Fro. 3. Kinetic curves of formation of reaction products in the presence of Coa+/KS-150; 1--tetral-l-one; 2--tetral-l-ol; 3--tetralin hydroperoxide; 4--1-oxy-keto-l,2,3,4-tetrahydronaphthalene; 5--1,1'-ditetralyls; 6--naphtho-l,4-quinone; 7--naphthol-1; 8-tetralin conversions. for a Co2+/KS-150 c a t a l y s t is close to t h e value derived o f t e t r a l i n o x i d a t i o n such as Co~+/SiO~ a n d Co (St)~. I n o r d e r t o e x a m i n e t h e f o r m a t i o n of main p r o d u c t s of h y d r o p e r o x i d e s of tetralin, t e t r a l - l - o n e a n d t e t r a l - l - o l Co2+/KS-150 and Co3+/KS-150, o x i d a t i o n was r e p e a t e d l y TABLE
4 . C O M P A R I S O N OF ATO~¢IIC C A T A L Y T I C A C T I V I T I E S
(ACA) OF
for active catalysts tetralin o x i d a t i o n - in t h e presence of carried out using a DIFFERENT
CATALYSTS
Reaction volume 2 ml
Catalyst
Amount of catalyst, g
Content of Co ion in the catalyst sample,
W × 104, mole/1. • •Sec
ACA x 10~3, mole/1. •sec. ion
% ~t.
Co~+/SiO, Co2+/BAU Co~04 Co(Sth Co*+/KS-150
0.100 0.025 0.100 0.015 0.050
0.50 1.38
1-80 0.40
10.00 2.07
4.80 6.70
1-50
3.60 1.15 1.15 3-10 3-24
diffuser. O x i d a t i o n was carried out at a t e m p e r a t u r e of 140 °. 5 g c a t a l y s t was used per 1. r e a c t i o n m i x t u r e . I t was previously shown t h a t a carrier containing c a r b o n has no m a r k e d effect on t h e yield of main p r o d u c t s of oxidation, corn-
A. ~. KA~NEVA et
9O
al.
pared with non-catalytic oxidation. Using a Co2+/KS-150 and Co3+/KS-150 catalyst changes the type of formation of reaction products (Fig. 2): the rate of formation of tetral-l-one, the intermediate reaction products increases, compared with other heterogeneous systems previously examined (Table 5). TABLE 5. INITIAL :RATEFORMATIONOF TETRAL-I-ONE IN TETRALINOXIDATIONON DIFFERENT CATALYSTS Temperature 140°C
Catalyst
Amount of catalyst, g/1. reaction mixture
Co~+/KS-150
5"00 5"00
Co~+/SiO~
4"99
Co3+/KS- 150
Catalyst
A_mount of catalyst, g/1. reaction mixture
mole/1., see
Co2+/BAU CoNaY 00804
6"00 5"00 6"22
17.96 4.79 9.25
Wo × 105,
mole/1. •see 31.8 24.4 6.20 18"4
Wo × 10 5,
In addition to examining kinetics of formation of main reaction products-tetral-l-one, tetral-l-ol and tetralin hydroperoxide--studies were made of the type and kinetics of formation of by-products of tetralin oxidation in the presence of a Co*+/KS-150 catalyst. Figure 3 shows kinetic curves of the formation of reaction by-products--naphtho-l,4-quinone, naphthol-1, 1-keto4-oxy-l,2,3,4-tetrahydronaphthalene and 1,1'-ditetralyls. For comparison, this figure shows kinetic curves of formation of tetral-l-one, tetral-2-ol and tetralin hydroperoxide. A study of these relations shows that reaction byproducts begin to be formed vigorously 80-90 min after the commencement of the reaction; the sequence of formation of these products is the same as in tetralin oxidation in the presence of a homogeneous catalyst--Co(St)2 [8] and several other heterogeneous catalysts [6]. SUMMARY
l. A s t u d y was made of the catalytic activity of heterogeneous catalysts prepared using variable valency metals and carriers containing carbon in liquid-phase oxidation of tetralin. 2. A cobalt cation applied on the surface of channel black (Ss,= 150 m*/g) has the highest catalytic activity. In the presence of this catalyst highest rates of formation can be obtained for tetral-l-one, the intermediate product. REFERENCES 1. L. N. PISHERSKH, V. I. ZAKHAROVA, N. I. ARTEMOVA and A. I. KAMNEVA,
Tr. Mosk. khim.-tekhnol, in-ta ira. D. I. Mendeleyeva (Proceedings of the D. I. Mendeleyev Chemical Technological Institute, Moscow). 14, 74, 1973
Oxidation of hydrocarbon fuels
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2. L. N. PISHERSKII, V. I. ZAKHAROVA, V. A. SELEZNEV, L. N. IVLEVA, Yu. V. BENTSIANOV and A. V. ARTEMOV, Tr. Tul'sk. ped.-in-ta, Tula, 5, 1973 3. A. M U K H E R J E E a n d W. F. GRAYDON, J. Phys. Chem. 71, 4232, 1967 4. N. P. BOEHM, Advances in Catalysis, L o n d o n - P a r i s 16, 179, 1966 5. Ya. B. GOROKHOVATSKII, Vtoroi sovetsko-yaponskii seminar 13o katalizu. N o v y y e dostizheniya v katalize (Second Soviet-Japanese Seminar on Catalysis. Progress in Catalysis). Tokyo, 1973 6. A. I. KAMNEVA, V. I. ZAKHAROVA, L. N. PISHERSKII, V. A. SELEZNEV a n d A. V. ARTEMOV, Neftekhimiya 15, 403, 1975 7. G. K. BORESKOV, K i n c t i k a i kataliz 14, 7, 1973 8. M. Ya. GERVITS, K a n d . dis. N.-i. in-t organ, poluproduktov i krasitelei (Post-graduate thesis. Scientific I n s t i t u t e of Organic I n t e r m e d i a t e Products and Dyes). Moscow, 1972
KINETICS OF OXIDATION OF HYDROCARBON FUELS BY DISSOLVED OXYGEN IN CLOSED VOLUME* G. I. K o v ~ E v and YE. T. DF,~ISOV I n s t i t u t e of Chemical Physics, U.S.S.R. A c a d e m y of Sciences
(Received 6 May 1975)
OXIDATIO:N of hydrocarbons is normally studies with continuous oxygen supply to the hydrocarbon oxidized (diffusion oxidation). However, in practice hydrocarbons are often oxidized in closed volume with oxygen deficiency. An example m a y be the oxidation of fuels with oxygen dissolved in fuel systems liberating heat. Products of oxidation formed cause a marked deterioration in operational characteristics of fuel systems. There are no results available in t h e literature concerning kinetic relations of oxidation under these conditions. This study is concerned with kinetics of oxidation of hydrocarbon fuels in closed volume with dissolved oxygen and a comparison with kinetics o f oxidation of fuels in a diffusion system. EXPERIMENTAL
The fractional and approximate chemical composition of the fuels examined is shown in Table 1. Commercial n-hexadecane was used as model hydrocarDon. * Noftokhimiya 16, No. 3, 457-464, 1976.