The study investigated the alkylation of diphenyl oxide with benzyl alcohol over HZSM-5 zeolite catalyst. Experiments were conducted in a glass reactor at 120°C for 3 hours with a catalyst loading of 100kg/m3. Analysis showed the reaction produced an isomeric mixture of benzyl-diphenyl-oxide. Kinetic studies established the reaction as pseudo-first order and found the activation energy to be 26.74kJ/mol. The catalyst was determined to be reusable with a conversion decrease from fresh to first reuse.

1. Study of Alkylation of Diphenyl Oxide with Benzyl Alcohol over HZSM-5 as Catalyst Ranjeet Kumar, D. Venkatesan and S. Sengupta* Department of Chemical Engineering IIT Kharagpur- 721302

4. Problems with Friedel-Craft alkylation :--- ---heavy environmental pollution due to waste generation ---troublesome product recovery & purification, ---catalysts cannot be reused, ---lower stability at higher temperature ---poor selectivity ---use of expensive acid-resistant material of construction

7. Fig 3.1 Schematic Diagram of Experimental Set-Up M Motor C Condenser R Glass Reactor T Thermometer OB Oil Bath TI Temperature Indicator / Controller Experimental Set-up Fully baffled glass reactor with electrically heated oil bath

10. Chemical equation (B) (A) HZSM-5 120 0 C benzyl alcohol is protonated and the carbocation formed, then it combines with diphenyl oxide in ortho and para position to give two isomeric mixtures as products

13. Kinetic Studies Effect of Speed of agitation on conversion of Benzyl alcohol Absence of solid-liq MT resistance as stirring went beyond 1100rpm

14. Kinetic Studies Effect of particle size on conversion of benzyl alcohol The conversion remained practically same within the range of the catalyst sizes. So intraparticle mass transfer resistance is insignificant & this support rxn as surface controlled.

15. Kinetic Studies Effect of catalyst loading on conversion of benzyl alcohol Due to increase in available acid sites, conversion increases linearly with increase In catalyst loading.

16. Kinetic Studies Plot of initial rate of reaction (r0i) against catalyst loading (w) Due to increase in available acid sites, initial rate of reaction increases linearly with increase in catalyst loading.

17. Kinetic Studies Effect of mole ratio on conversion of Benzyl alcohol Mole ratio is diphenyl oxide to benzyl alcohol, no effect on diphenyl oxide conversion, whereas benzyl Alcohol conversion increased With increase in ratio

18. Kinetic Studies Effect of temperatures on conversion of Benzyl alcohol Clearly, conversion increases with increase in temperature

19. Kinetic Studies Kinetic plots for various temperatures Rate constants, k1 = 2.26*10 -5 (373K), 2.93*10 -5 (383K), 3.689*10 -5 (393K), 4.265*10 -5 (403K), s -1

20. Kinetic Studies Arrhenius plot From the slope of this graph Apparent activation energy was calculated, Ea=26.74KJ/mol High value of Ea shows that rxn is kinetically controlled & occurs at the surface of catalyst

21. Kinetic Studies First order reaction plots: effect of catalyst loading plot of –ln (1-X A ) vs. time was made for this reaction at various catalysts loading. All of these plots show straight lines passing through the origin. Their linearity confirms the first order reaction

22. Kinetic Studies Effect of reuse of catalyst Reusability of catalyst… Filtered from rxn mixture & heated at 550 o C to burn off the reactants & products from pores. Conversion of Benzyl alcohol became 31.82 to 18.77% from fresh to 1 st reuse

25. THANKS!