Alkylation of phenol by n-decene-1 on deprotonized aluminosilicates

I . T . GOLUBCHENKO et al.

192

REFERENCES

I. J. K. DIXON and K. W. SAUNDERS, Ind. and Eng. Chem. 46, 652, 1954 2. Chem. and Eng. News 60, 22, 20, 1982 3. J. M. WATSON, C. H. FORWARD and J. R. BUTLER, U.S.A. Pat. 4417085; RZh Izobreteniya Stran Mira 57, part 2, 4, 115, 1985 4. L. G. CHUB, Yu. N. GARBER and E. I. EL'BERT, Koks i khimiya, 4, 31, 1974 5. Kataliticheskiye svoistva veshchestv. Spravochnik (Catalytic Properties of Substances. Handbook), (Ed. Ya. B. Gorokhovatskii), Vol. 4, 296 pp., Naukova Dumka, Kiev, 1977 6. F. J. SODERQUIST, J. L. AMOS and H. D. BOYCE, U.S.A. Pat. 3259666, O.G. 8 2 8 , 1, 56, 1966 7. O. V. ZOLOTAREV, I. Ya. PETROV, B. G. TRYASUNOV and E. I. EL'BERT, Nestatsionarnye protsessy v katalize: Tez. dokl. II[ Vsesoyuz. konf. (Transient Processes in Catalysis. Preprints of Papers of Third All-Union Conference), part 2, p. 68, Novosibirsk, 1986 8. G. K. BORESKOV, Geterogennyi kataliz (Heterogeneous Catalysis), 304 pp., Nauka, Moscow, 1986 9. L. I. MARIICH, Gazovaya khromatografiya v kontrole koksokhimicheskogo proizvodstva (Gas Chromatography in Control of Byproduct Coking), 192 pp., Metallurgiya, Moscow, 1979 10. N. I. KOL'TSOV and S. L. KIPERMAN, Teoret. i eksperim, khimiya 12, 6, 789, 1976

P~rol. Chem. U.S.S.R. Vol. 28, No. 3, tap. 192-196, 1988 Printed in Poland

0031-6458/88 $10.00+.00 © 1990 Pergamon Press lalc

ALKYLATION OF PHENOL BY n-DECENE-1 ON DEPROTONIZED ALUMINOSILICATES* I. T. GOLUBCHENKO, P. N. GALICH, V. I. KHRANOVSKAYA a n d V. G. MOTORNYI Department of Petroleum Chemistry of Institute of Physicoorganic Chemistry and Carbon Chemistry, Ukr.S.S.R. Academy of Sciences, Kiev

(Received 11 November 1987)

EARLIER we showed [1, 2] that, in the presence o f y-A12Oa, p h e n o l is a l k y l a t e d selectively b y ~t-olefins with the f o r m a t i o n o f m o n o s u b s t i t u t e d alkylphenols with substituents in the ortho-position. Here it was suggested [3] t h a t selective f o r m a t i o n o f o - a l k y l p h e n o l s on a l u m i n i u m oxide occurs with the p a r t i c i p a t i o n o f L e w i s - t y p e acid centres, the existence o f which was established in other studies [4--8]. A t the s a m e time it is k n o w n that, in the presence o f a m o r p h o u s a n d crystalline aluminosilicates possessing Bronsted- a n d Lewis-type acid centres [5, 9, 10], a l k y l a t i o n o f p h e n o l by * Neftekhimiya

28, N o .

5,

636-639, 1988.

Alkylation of phenol by n-dec~ne-I

193

olefins proceeds non-selectively: a mixture of o- at~.d p-isomers is formed [11-13]. In connection with this it was of significant interest to investigate the alkylation reaction of phenol by ~-olefins on an aluminosilicate catalyst without protonic acidity. iRESULTS AND DISCUSSION

A deprotonized catalyst specimen was obtained by repeated treatment of an industrial aluminosilicate cracking catalyst with art aqueous solution of sodium nitrate before ion exchange had ceased [14, 15]. The absence of protonic centres in the modified catalyst specimen ,~'as monitored by taking IR spectra of adsorbed pyridine, and also by means of Hirschler indicators (arylmethanols). IR spectra of pyridine adsorbed on the initial base aluminosilicate catalyst adopted for ion exchange and modified with sodium are given in the Figure. It can be seen that on the initial aluminosilicate there are characteristic bands in the 1540 and 1450 cm -1 region. These bands are attributed to protonic and aprotic acid centres respectively [4-10]. On modified aluminosilicate there is only a characteristic pyridine band in the 1450 cm -1 region, which is attributed to pyridine coordination-combined with a Lewis acid. The characteristic band of a pyridinium ion in the 1540 cm-1 region is not observed. This is also confirmed by Hammett and Hirschler indicators. Thus, if diphenylmethanol and triphenylmethanol used to determine the protonic acidity of catalysts [5, 9, 16] were given the colour characteristic of the acid form in the presence of industrial aluminosilicate, then on a specimen modified with sodium such colouring of the indicators did not occur. On both the catalysts investigated, Hammett

l

1

7400

1500 IGO0 F,-eouencj , crn -I

I"700

Infrared spectra of pyridine adsorbed on industrial (I) and deprotonized (2) a]uminosi|icate (vacuum treatment at 500°C).

indicators (anthraquinone, benzylacetophenone, dicinnamylacetone, 4-o-to]yl-otoluidine, p-dimethylaminoazobenzene, neutral red) used to determine overa]| acidity [5, 9] (protonic and aprotic) acquired the colour characteristic of the acid form.

An investigation of the catalytic pi-operties of the initial specimen of aluminosilicate catalyst and the catalyst modified with sodium was carried out on a model

"i. T. GOLUBCHENKOel aL

194

reaction of alkylation of phenol by n-decene-1. Freshly distilled phenol and n-decene-1 were used. Their physicochemical chalacteristics corresponded to those given in the literature [17, 18]. Experiments were conducted on a normal vertical flow-type unit. Reaction products were analysed by gas-liquid chromatography on a Khrom-4 instrument with a flame-ionization detector by the following procedure. A column of stairdess steel (250× 0.3 cm) was filled with chromaton N-AW (0.2-0-25 ram) containing 5% silicone elastomer SE-30 used as the stationary liquid phase. The initial temperature of the chromatographic column was 90°C, but 2 rain after the sample had been introduced it was programmed at a rate of 12 deg/min to 240°C. The temperature of the evaporator was 320°C. The carrier gas was helium. Experimental data are presented in the Table. For comparison, the results of experiments obtained during alkylation of phenol by decene-1 in the presence of ~-AlzO~ are also given in the Table. It is evident that on the initial specimen of industrial aluminosilicate catalyst alkylation of phenol by n-decene-1 proceeds non-selectively at a temperature of 160°C with the formation of monosubstituted alkylphenols with substituents in the ortho- and para-positions, the amount of o-isomers formed being twice as great as the amount of p-isomers. Increase in the alkylation temperature to 200°C does not lead to any change in the nature of the process, but is accompanied solely by an increase in the yields of the catalysis products. Of note is the intense formation of dialkylphenols, the content of which in the alkylate varies from 15 to 20~o in the temperature range investigated. ALKY'LATION OF PHENOL BY n-DECENE=I ON ALUMINO~ILICATE CATALYSTS AND ~'-A1203

Volumetric rate 1 hr -1, phenol/olefin= 1 Composition of alkylate, wt. % monoalkylphenols

Industrial 160 aluminosilicate 200 Deprotonized 160 aluminosilicate 200 ~,-AI2Oa 160 200

27 8 52 35 47 19

22 12 35 25 32 14

6 9

25 39 7 34 12 64

~ ~

11 2!

15 20 6

-

3

~

~

,

~ o

~ '~

o ~ ~

~' B

25 39 7 34 13 64

46 44 58 83 61 94

55 87 13 42 21 68

A different picture is observed during alkylation of phenol by n-decene-1 on deprotonized aluminosilicate. In this case, as in the presence of ?-AlzO3, monosubstituted decylphenols with substituents only in the ortho-position are formed. At 160°C, besides alkylphenols, the reaction products contain 6 wt. ~o decylphenyl

AlkylatiOn of phenol by n-dec~n¢-i

195

ethers. It is interesting that, in the presence of aluminium oxide, decylphenyl ethers (9 % wt.) are also formed at this temperature. Thus the experimental data obtained indicate the identical nature of alkylation of phenol by n-decene-1 on deprotonized ahiminosilicate and on aluminium oxide. In the presence of the industrial aluminosilicate catalyst, alkylation of phenol by ~-olefins probably proceeds by two mechanisms. At the aprotic centres of aluminosilicates it is similar to the mechanism by which alkylation occurs on aluminium oxide [3]. The mechanism of formation of o-alkylphenols with the participation of these centres can be presented by a scheme including transition of the aprotic acid to protonic acid on account of the formation of a "Lewis acid centre-phenol molecule" surface complex. In this case the free electron pair of the oxygen atom of the hydroxyl group of phenol is evidently transferred to the free orbital of aluminium, as a result of which the O - H bond is weakened and the hydrogen atom is protonized. Then a carbonium ion is formed from the olefin and proton, which together with the adsorbed fragment of the benzene molecule forms a new surface cordplex transformed into o-alkylphenol with the release of a Lewis acid centre: 4-

H--O_p h - - L ~ + PhOH ~ --L---- -[- CH2=CH--R

I

1

CH3 \ H CH--IR N,/

CHa R__HC/_~__ph

0--./. = ~ •

=

.

=-L--[

OH ~|

CH, [ +--L--

h

'

In the presence of protonic centres of aluminosilicate, phenol is alkylated by ~-olefins by the classic carbonium-ion mechanism with the formation of a mixture of o- and p-isomers. The experimental data obtained confirm the correctness ol~the earlier assumption [3] that selective formation of o-alkylphenols during alkylation of phenol by olefins proceeds at aprotic acid centres. Consequently, for selective o-alkylation of phenol it is necessary to use catalysts that possess only Lewis-type acid centres. CONCLUSIONS

1. A model reaction of alkylation of phenol by n-decene-I on a deprotonized aluminosilicate catalyst has been studied. 2. It has been established that selective formation of o-alkylphenols during alkylation of phenol by ~-olefins in the presence of deprotonized aluminosilicate occurs at Lewis-type acid centres.

i . T . GOLUBCHENKOet al.

196

3. A m e c h a n i s m of selective ortho-alkylation of p h e n o l with the participation of these centres is put forward, including t r a n s i t i o n of aprotic acid to p r o t o n i c acid on account of the f o r m a t i o n of a "Lewis acid c e n t r e - p h e n o l molecule" surface complex. REFERENCES 1. I. T. GOLUBCHENKO, V. G. GOTORNYI and P. N. GALICH, Neftepererabotka i neftekhimiya 18, 3, 1980 2. I. T. GOLUBCHENKO, V. G. MOTORNYI, O. I. GAPONENKO, I. A. MANZA and P. N. GALICH, Neftepererabotka i neftekhimiya 9, 19, 1980 3. I. T. GOLUBCHENKO, Dokl. Akad. Nauk USSR, Set. B, 10, 43, 1980 4. Kh. P. BOEM, Katali2. Stereokhimiya i mekhanizm organicheskikh reaktsii (Catalysis. Stereochemistry and Mechanism of Organic Reactions), 268 pp., Mir, Moscow, 1968 5. L. A. IGNAT'EVA and R. Kh. KHALILOVA, Zh. prikl, spektroskopii 5, 5, 642, 1966 6. T. V. ANTIPINA, O. V. BULGAKOV and A. V. UVAROV, Osnovy predvideniya kataliticheskogo deistviya (Principles of Foreseeing Catalytic Action) vol. 2, p. 345, Nauka, Moscow, 1970 7. K. TANABE, Tverdye kisloty i osnovaniya (Solid Acids and Bases), 184 pp., Mir, Moscow, 1973 8. N. I. GASANOVA, A. Ye. LISOVSKII and T. G. ALKHAZOV, Kinetika i kataliz 17, 4, 1068, 1976 9. K. V. TOPCHIYEVA and KHO SHI TKHOANG, Aktivnost' i fizikokhimicheskiye svoistva vysokokremnistykh tseolitov i tseolitsoderzhashchikh katalizatorov (Activity and Physicochemical Properties of High-Silicon Zeolites and Zeolite-Containing Catalysts), 168 pp., lzd. MGU, Moscow, 1976 10. L. LITTL, Inffakrasnye spektry adsorbirovannykh molekul (Infrared Spectra of Adsorbed Molecules), 514 pp., Mir, Moscow, 1969 11. G. D. KHARLAMPOVICH and Yu. V. CHURKIN, Fenoly (Phenols). 376 pp., Khimiya, Moscow, 1974 12. L.A. POTOLOVSKll, V. N. VASIL'EVA, T. I. KIRSANOVA, N. M. KUKUI, K. I. ZIMINA and G. G. KOTOVA, Khimiya i tekhnologiya topliv i masel, II, 27, 1970 13. N. L. VOLOSHIN, Ye. V. LEBEDEV, E. K. BRYANSKAYA, V. T. SKLYAR and Yu. A. SERGIYENKO, Sovershenstvovaniye tekhnologii proizvodstva prisadok (Improvement of Additive Production Methods), p. 269, Naukova Dumka, Kiev, 1976 14. K. G. MIESSEROV, Dokl. Akad. Nauk SSSR 87, 4, 27, 1952 15. K. V. TOPCHIYEVA, A. P. BALLOD and I. V. PATSEVICH, Izv. Akad. Nauk SSSR, Set. khim., 3,478, 1954 16. A. E. HIRSCHLER, J. Catalysis 2, 428, 1963 17. E. Ye. NIFANT'EV, Kratkaya khimicheskaya entsiklopediya (Concise Chemical Encyclopaedia) vol. 5, p. 395, Soy. Entsiklopediya, Moscow, 1967 18. Fiziko-khimicheskiye svoistva individual'nykh uglevodorodov (Physichemical Properties of Individual Hydrocarbons), (Ed. V. M, Tatevskii), 412 pp., Gostoptekhizdat, Moscow, 1960