Applied Reaction Kinetics: Fundamentals and Applications - Industrial

Industrial & Engineering Chemistry · Advanced Search .... Applied Reaction Kinetics: Fundamentals and Applications. K. H. Lin. Ind. Eng. Chem. , 1969,...
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APPLIED REACTION KINETICS Fundamentals and Applications This r e v i e w of 1 9 6 7 - 6 8 literature concentrates on f u n d a m e n t a l kinetic studies a n d also covers less c o m m o n reactions. Some of t h e m a t e r i a l w h i c h appeared i n t h i s r e v i e w i n previous years is now covered b y t h e A n n u a l Review of Chemical Reaction Engineering (I&EC, February 1 9 6 9 )

n view of the rapidli- growing volume of the kinetics

I literature available, the literature analysis on this sub-

ject has been reorganized. The areas of kinetics related to catalysis, polymerization, and reaction engineering are omitted from this section of the review and are covered by other authors. T h e section on Polymerization Kinetics appears in this issue of ISLEC. The literature selected from that published during 1967-68 was classified in more detailed categories than in previous reviews. This change is especially emphasized in the section on Fundamental Studies-Experimental. An attempt has been made to unify the symbols whenever possible, and those generally accepted are used with little or no explanation. Thus, the symbols r, k , t , C, and T in most cases represent the rate of reaction, rate constant, time, concentration, and absolute temperature, respectively. Subscripts usually refer to the particular species taking part in the reaction. Basic experimental studies of kinetics and mechanisms continued to be major activities. The great majority of the investigations dealt with organic reactions. Some of the “unconventional” techniques have been gradually gaining popularity in the field of reaction kinetics. Literature on the types of reactions classified as “less common” appears to be undergoing an accelerating growth. Especially notable are the applications involving shock waves, plasmas, and ionizing radiations. Studies of fundamentals on the pilot-plant a n d commercial scale are still scarce.

F U N D A M E N T A L STUD1 ES-EXPERIMENTAL Experimental Techniques

Radioactive tracers. An apparatus capable of following chemical reactions taking place in the droplets of salt solutions has been reported ( I A ) . T h e technique is based on measurement of the change in radioactivity of the droplets and/or the effluent gases which have been previously labeled with a suitable radioisotope. The influence of various parameters on the kinetics of reaction can be studied with the apparatus. T h e rate of isotopic exchange between nickel ions and bis(dioximat0)-Ni(I1) complexes in pyridine has been determined using a radioactive mixture of 63h-iand jgNi in the form of chlorides ( 2 A ) .A gas-flow counter measured activity; rates of reaction at various temperatures and values of activation energy were calculated from the 42





activity data. T h e rate of incorporation of radiotracer 6OCo ion in the Zn(I1)-EDTA chelate was utilized in deriving a rate equation describing the kinetics of Co(I1) ion substitution ( 3 A ) . 65Zn or 35S was added to the reacting mixture as a tracer in the study of heterogeneous reactions between ZnO and tetramethylthiuram disulfide in xylene, in rubber, and in the solid state ( 4 A ) . Zinc oxide was separated from a sample of the reacting mixture, its radioactivity determined, and the rate constant k calculated from the equation: dC - k(C0 - C ) / C


where COand C are the concentrations of tetramethylthiuram disulfide at the beginning and at time t , respectively. The rate-controlling step is the chemical reaction, but not diffusion. T h e advantages of using l3II over a quartz balance or the autoradiography in the study of iodination of metals are the applicability of the technique to thick or liquid metal specimens in a closed space or in a n iodine solution and its better sensitivity and control ( 5 A ) . The technique and apparatus have been described in the investigation of iodination kinetics of lead and silver. Resonance method. I n the esterification of acetic anhydride (A) with methanol (M), the increase in the methoxy proton signal intensity of the ester determined by N M R spectroscopy has been interpreted in terms of a second-order rate equation (6Aj:


r = kCACk

ESR spectrometry was used to follow the course of reaction between oxygen atoms and SO at 299 k 2 OK under the total pressure of 0.7 to 3 torr ( 7 A ) . T h e kinetic data thus obtained lead to the following mechanism:





0 so2 0 2 so3 0 2 0 SO2 Ar ----f SO3 Ar O + S 0 2 f S O z ~ S O 3 f S O z




T h e phenomenon of an ESR signal growing to a maximum value rapidly and then decaying gradually has been observed in both the reaction of 2,2-diphenyl-l-picrylhydrazyl with 4-isopropyl-2,6-di-tert-butylphenol(8A) and the formation of the tetracyanoethylene anion in a number of strong donor solvents (9A). I n the former case ( 8 A ) , this phenomenon is attributable to variation in the concentration of the reaction intermediate.

Another application of the ESR method has been SO illustrated (10’4) in thereaction 0 COS -+-CO in a flow system. T h e concentration of oxygen atoms was determined by an ESR spectrometer, and a mass spectrometer measured the concentrations of the stable products. Parameters for the Arrhenius equation were computed from the experimental data. Spectroscopy. Kinetics studies on fast bimolecular and termolecular reactions in gas phase have been carried out by Meyer ( I I A ) in an apparatus which combines the flash photolysis and the time-resolved spectrometry. A series of technical papers by Greiner (12A-14A) described the determination of rate constants and activation energies by quantitative kinetic spectroscopy for the room temperature gas phase reactions. T h e reactions involve OH radicals with Hz, CO, and CH4 (124); OH radicals with C ZH 6, C BH 8, and iso-C 0 (13A); and O D radicals with C H 4 and C zH 6 (144). A sharp drop in the rate of reaction between KMnO4 and HzOz with an increasing HzOz concentration was detected by an ultraviolet spectrophotometer and was attributed (15A) to formation of M n ( H 2 0 2 ) i f . T h e reaction rate in terms of the MnO; concentration, C,, is represented by:



Emission ihtensity measurement. The decay of the infrared emission intensity from t h e f u n d a m e n t a l vibratioh-rotation band at elevated temperatures can be related to the reactant concentration. This property has been utilized in a study of the H F decomposition in a shock tube in the temperature range of -3800” to 5300 O K (16A). A nonequilibrium digital computer program was used in the evaluation of rate constants from the‘experimental H F concentration-time data. A technique similar to the one above measured the growth of “blue continuum’’ emission during the induction period of the reactions involving Hz, CO, 0 2 , and Ar a t 1100” to 1700 O K (17A). The measured emission intensity, I , has been correlated with a factor, a , which is related to the branching chain reaction kinetics of Hz-02 combustion: I =Io exp(a t ) . Arrhenius parameters for the reactions were derived from the experimental data. I n a separate study dealing with the recombination of nitrogen atoms and their reaction with methane, the rate constants were also obtained from the emission intensity data (18A). VOL.







Differential thermal analysis. Based on the principle that the heat effect is proportional to the rate of the reaction, the differential thermal analysis (DTA) was employed in investigating the bromination kinetics of cyclohexene in CC14 (19A). The method records the heat effect during the reactions in terms of the temperature differences. The kinetics of dehydration of CuSO4 5H20 and oxidation of UOZ in an air stream have been studied by a flowing gas DTA technique (20A). T h e apparatus permits gas to flow through a reference and the sample. Three endothermic peaks are present in the DTA curves for the dehydration of CuSO4 5Hz0, while the curves for oxidation of U O z show two exothermic peaks. An application of DTA was also reported (21A) in the catalytic hydrogenation of benzene and (C6H5) zNH at high temperatures under high pressure (-1400 psi). Polarography. This technique is capable of following chemical reactions involving no electrodes as well as those under the influence of electrode reactions. T h e chemical reaction may or may not accompany a change in the oxidation potential depending upon whether the reaction precedes, is initiated by, or follows the electrode reaction. A discussion by Masek (22A) concerns with various types of reactions and examples are presented to show the degree of complexity of reaction mechanisms that may be studied by polarography. T h e result of a polarographic study of the oxidation of sulfites by dissolved oxygen has led Rand and Gale (23A) to the following rate equation: r = kC;Ga3Cy! This equation is valid only in certain ranges of p H and oxygen concentration; with lower concentration of oxygen, the mechanism becomes somewhat more involved. Polarograms and curves of current us. time for the catalytic evolution of hydrogen in pyridine protonation under 1 to 2500 atm nitrogen have revealed some unusual pressure effects on the kinetics expressed by (24A):

0 for reactions on Co, Fe, and W, implying that the oxygen transfer is inhibited by the high concentration of adsorbed oxygen on these three metals. A separate study by Walsh and coworkers (126A) on the oxidation of tungsten by COZ at high temperatures (2200" to 3200 OK) has indicated that the rate below 2650 "K is practically independent of the gas flow rate. The implication of this observation is that the process is controlled by the chemical reaction at the surface up to about 2650 "K. Above this temperature, the gas flow rate appeared to be the rate-determining factor, and the reactions of desorbed oxygen atoms became significant. T h e oxidation of copper sulfide displays different




NO. 3 M A R C H 1 9 6 9



kinetics and mechanism depending upon whether the reaction is carried out in a fixed bed or in a fluidized bed (127A, 128A). At temperatures to 400 "C and oxygen partial pressures to 0.1 atm, the reaction is autocatalytic in a fixed bed and proceeds according to: log[a!/(l - a ! ) ]


kPg log t


I n the above equation, a! is the fractional conversion (50.95) at time t , Po is the partial pressure of oxygen, Cis the constant, and m is the reaction order. The activation energies have been evaluated by Ganguly and Mukherj ee (1.274 separately for the induction, acceleration, and deceleration stages. The oxidation in a fluidized bed of CuS mixed with ignited alumina (to facilitate fluidization) is not autocatalytic, and two rate equations are employed to describe the kinetics (1284. The rate of reaction of HzS and COS with F e z 0 3 in bauxite at 150" to 350 O C is determined by the degree of the solid phase conversion, and FeS and FeS2 are the only solid reaction products involved. The reaction rate has been shown by Korobeinichev (129A) to be first order in H2S and zero order in COS and is accounted for by the following two-step mechanism: 1/3Fez03


+ +


HZS --+1/3FeSz 1/3FeS HzO COS HzO +HzS COz T h e first reaction is fast and is catalyzed by A1Z03 in bauxite and the second reaction regenerates H2S. A systematic study on the simultaneous oxygen absorption a n d chemical reaction i n the solutions of ("4) zS03 by Navratil and Nyvlt (130A) has resulted in an equation expressing the rate of oxygen uptake, R g


R = c,,,lO-ksl*dkdT/v d i where C ,, is the oxygen solubility in distilled water at absolute temperature T , F is the ionic strength, and v is the viscosity; k,, kd, and k are represented, respectively, by: k , = (~i/C,,,)/P kd = D u / T and




+ k2Cz





Reaction as affected by acids and bases in organic solvent; -20-0 O C ; k , A . P . , equilibrium constant, mechanism (804 Acetone Bromination using oxidation-reduction cell; 24-45 "C; k and A.P. for catalytic and noncatalytic reactions Alkyl hydroperoxides Acid-catalyzed decomposition; 20-50 OC; k , A.P., mechanism Aniline Diazotization catalyzed by thiocyanate; 5-25 OC;k , A.P., mechanism Aromatic and aliphatic Esterification with ethylene glycol; 140-190 OC; carboxylic acids k , A . P . , reaction order (2-2.5) Aryl amines Acylation by aromatic sulfonyl chlorides in benzene; 55 O C ; k (1st order) Azo compounds Decom osition in various solvents; 40-110 OC; k, A,#., ultraviolet absorption maximum Benzoyl peroxides Decom osition induced by triphenylmethyl; 15-3POC; k (2nd order), A . P . , mechanism Oxidation of dialkylamino alcohols in benzene; 20-40 'C; k, A.P. Crotonaldehyde Alkaline hydrolysis and condensation with acetone; 20-48 OC; k , A.P., ultraviolet absorption at 220 m,u N,H-Dimethylnitrosoamine Thermochemical and kinetic studies; standard heats of combustion, formation, and evaporation, k , A.P. N,N-Diphenylhydrazine Oxidation with oxy en atom in aromatic solvents; 30-75 k (2nd order), spectrophotometric data (914 Glyceraldehyde Isomerization to dihydroxyacetone in presence of various anions; 50 OC, pH 4-8; k , polarogram (924 1-, 2-Haloanthraquinones Reaction with sodium methoxide in anhydrour methanol; 100-120 ' C ; k , A.P., yield (934 Isocyanate Reaction with acetic and benzoic acid (944 hydrazides: 15-35 OC; k, A . P . Mcthylaniline Ac lation with acid anhydrides; 0-40 O C ; k &nd order), A . P . (%A) Effect of solvent on rate of reaction with Ehenyl glycidyl ether; 100 OC; k , A . P . , ammet constant r h o (964 Nitrogen oxide, Reaction in solution and in gaseous phase; ammonium carbonate 11-18 O C ; product composition, absorption coefficient, k (974 Olefinic compounds Epoxidation by peracetic acid; 20-50 O C ; k. A . P . (@?A\ Reaction of epoxidized oil with acetic acid; 20-50 ' C ; k (1st order), A . P . (994 Propylene oxide, Reaction in presence of BFa, (C9Hs)zO; alcohols 20-30 O C ; k , A.P., product composition, ( IOOA) mechanism Sulfanilamides Effect of acyl substituents on rate of alkaline hydrolysis; 50-70 OC; k (pseudo 1st order), A . P . , Hammet constants (lO7A) trrt-Butyl triphenylmethyl Decomposition in benzene catalyzed by peroxide benzene-sulfonic acid; 2O-GO O C ; k , A . P . , mechanism (702A) Trifluoroacetic esters Isotopic hydrogen exchange in acid media; k , acidity function values, mechanism (703A) 1,l ,l-Trifluoro-ZBromination; 350-450 O C ; k , A.P. (104A) chloroethane Trimethylolpropane Esterification with adipic and sebacic acids; rate curves, k, A.P. (7054) Vinyl chloride Pre aration from dichloroethane; 300-400 O C ; agsorption coefficient, k (1st order) (106A) Vinylbutyl ether, Addition of ethanol and acetic acid to vinyl acetate double bond; 20-60 " C ; k, A . P (107.4)




I n these equations, Ci refers to the solubility of oxygen in (NH4)zSO3 solutions, D is the diffusion coefficient of dissolved oxygen in the solution, C1 is the concentration of ammonium dithionite, and C2 is the concentration of sulfite and dithionite. Thermal decomposition. Ammonium metavanadate (NHdVO,) powder (10 to 40p size) begins to decompose rapidly at 160 "C into (NH4)2VGOlE, NH3 gas, and water vapor with a short induction period. The mass spectrometer data for the reaction indicated that the kinetics can be approximated by the model for a contracting sphere with a radial propagation at a constant rate (131A): (k/a) t = l - ( l - ~ ) " ~ where a is the radius of the sphere and a! represents the fraction decomposed. According to Deschanvres and CHEMISTRY


Study and Data

Acetaldehyde, peracetic acid




k, rate constant; A.P., Arrhenius parameters.

Nouet (131A), accurate values of (k/a)may be obtained for fine particles by plotting the effective reaction yield against t. Good agreement between experimental data and the contracting sphere model was also obtained in the dehydration of calcium sulfate dihydrate in vacuum at 85 "C (132A). The nuclei growth equation is applicable to the solid-state reaction between BaC03 and ZnO (133A), as well as to the decomposition of MgSO 4 at 920" to 1080 "C (134A). Thus, in the latter case, Hulbert (134A) has shown that the rate may be satisfactorily described by



the nuclei growth equation (kt)" = - In (1 - x ) with m = 1.10, and x referring to the degree of reaction completed. Both the sample mass (0.05 to 100 g) and the pelletization pressure exert appreciable influence on the decomposition rate. The rate equation in the former case (133A) assumes the form: kt = --In (1 - x ) ~ ' ~ Rate constants and activation energies have been evaluated for the thermal decomposition of tricalcium phosphate, Ca3(P04)2, in the temperature range 1350' to 1500 "C based on the following mechanism (135A):

ki Ca3(PO4)2 --+ CazP207



+ CaO + 3 C a 0 + PzO5 k2

2Ca0 Ca(P03)z --+ T h i s mechanism of producing P 2 0 directly from Ca3(POd)z can be made irreversible by the addition of excess Si02 to react with CaO. Kinetics and Mechanism-Organic


Synthesis, formation, a n d miscellaneous reactions. T h e r a t e of r e a c t i o n b e t w e e n e t h y l e n e o x i d e a n d oleic acid at 80 "C in the synthesis of ethylene glycol monooleate (157A) depends on the addition agent used as the catalyst-e.g., KOH, (CHB)2NPH, and (CH3) 2N C G H l l . With KOH as the catalyst, the rate was first order in each reactant and in the catalyst used. I n the presence of other catalysts, the reaction order with respect to oleic acid became zero. A mechanism was proposed to account for the higher catalytic activity of tertiary amines. T h e formation of ether from ethanol over y-alumina at 150" to 195 "C under 30 to 300 torr in ethanol is pressure sensitive and strongly retarded by the presence of water vapor. The reaction rate in terms of partial pressure of alcohol, PA, and of water? Pw, has been derived by Knoezinger and Ress (158A): r = ro ( P i / 2 ) bP,) where ro is the rate at Pw = 0 and b refers to the ratio of the absorption coefficients of HzO and ethanol. According to Benson and Shaw (159A),the hydrogen atom addition to propylene, toluene, or xylene takes place by the mechanism: Hz e 2 H', H' RCH3 RH CH: CH4 H' CH,' f H2 from which the following rate equation is developed:






K;I2 k Z C R C H ,



Reaction Order with Respect t o

Study and Result

Heterogeneous reaction; 500-650 OF; rn, k , A . P . Empirical Thermal decomposition; Ammonium 200-80 'C; m, k , A.P., perchlorate rate equation Empirical Effect ofSe com ounds on Ammonium sulfite oxidation of; $0 'C, broad ranges of acidity and concentration; m, rate curves Thermal decomposition; Barium azide 120-45 "C; rate equation, m, k , A . P . Empirical Dissolution and decom osi Borates, natural tion in "08; 25-98OG m, k , A . P . Complex Carbonation by COz, Calcium hydroxide effects of agitation, concentration, time, temperature; 25-35 OC; m, k 1(COz) Slow oxidation by 02. Carbon black 300-600 OC, 0.1-1 i t m 0 2 : m, k, A . P . 1 N 0.5(0d Reaction with water vapor; Carbon -900 OC; m, rate equation, k Complex Oxygen exchange on carbon; coz, co 750-850 "C; m, k , A . P . , equilibrium constant Complex Gas-phase reactions with Carbon monoxide Clz, NOS; 381-473 'C; m,k, A.P. Complex Oxidation by Ce(IV) in l(Ce); Complex Hypophosphite HzSOa; m, k , rate equation (hypophosphite) Effect of S o a on oxidation Lead sulfide of; 500-1000 OC; m, rate equation, industrial application Empirical Nickel and zinc oxides Reduction by Hz; 350-500 "C; m, k , A . P . , rate equation Empirical Nitrogen oxide Reaction with water vapor; 102-425 OC; rate of " 0 8 formation, composition of feed and product ...... Peroxydisulfate ion Reaction with ferrocyanide ion: m, k , catalytic 2 (Overall) constants Plutonium Reduction by HzOz in acid solutions; m, k , A . P . Complex Silver azide Thermal decomposition in molten state; 309-340 OC; rate equation, m, k , A . P . Empirical Sodium and potassium Thermal decomposition in drum furnace; 110-140 OC carbonates (NazCOa), 155-175 OC (KzCOa); m. k , A.P.. rate equation ' ' Empirical Sulfur Reaction with phenol in alkaline solution; 120-165 'C; m, k , A.P.,catalytic influence of addition agent Complex Titanium dioxide Chlorination in molten salts containing FeCla; m, k Complex Uranium oxide, uao8 Reaction with Fe(II1) in HzSOa; 20-50 OC; m, k , A.P. '/s [Fe(III)I Aluminum, chlorine







Rej. (736A) (737A)

(7384) (739A) ( 740A)

(147A) (142A) (743A) (144A) (745A) (746A)



(749A) ( 750A)

(1514 (7524


( 754A)

(755A) (756A)

a k , rate constant; A.P., Arrhenius parameters; m, mechanism.


The values of K I and k2 have been determined and the resulting rate equation is reported to be valid over a wide range of reaction conditions. The influence of slurry particle geometry on the kinetics of a reacting slurry system has been demonstrated by Polinski and Huang (160A) in the reaction of alkyl chlorides with sodium acetate particles. The effects were observed, for example, in the shift of the kinetics of the reaction from first to zero order as the particle geometry and state of aggregation were changed and in the reduction of activation energy from 20 to 10 kcal/mol. A

model was proposed in which a reaction under chemical reaction control could return to mass transfer control. T h e spontaneous acylation of substituted aniline (A) by dimethyl ketene (D) in ether solution involves two paths, in one of which a second aniline molecule functions as a catalyst (161A). This mechanism is based on the fact that the experimental results can be described by: -TD = (klCA f k2Ci)CD = kobsCD The rate constants k l and kz are dependent on the base strength of aniline as well as on functions of the temperaVOL.


NO. 3 MARCH 1969



TABLE IV. ADDITIONAL REFERENCES ON KINETICS AND MECHANISM-ORGANIC M a j o r Reactants Acetaldehyde Acetylene Acid chlorides Aliphatic glycols Alkylphenols, formaldehyde Allyl alcohol Aromatic nitrated alcohols Benzaldehyde 3-Bromopentane Chloroacetic acid Coal

Cobalt and nickel formates Coke Cumene peroxide Cvclohexadienes



Dibutyl phosphate

Dicobalt octacarbonyl Difluoramine 3,3-Dimethyloxetane 1-Ethoxyethyl chloride Ethyl acetate Ethyl nitrate

Sttidj and Result

Reaction Order with Respect t o

Reaction with atomic hydrogen in a dischargeflow system; 300 O K ; tn, k Complex Dimerization in aqueous CuzCIz solution; m, k Complex Alcoholysis in a rotic m, k 3(0verall) solvents; 25 Esterification by acrylic and 2(0v~rall) methacrylic acids; m, k Reaction in alkaline media; k , A.P. Z(0verall) Iodination in aqueous solution; 20 " C ; m , k , A . P . Complex Decomposition in alkaline medium; 25 ' C , p H 8.15, ionic strength 0.2; m, k Pseudo-first Liquid-phase oxidation in benzene in presence of olefins; m , k ...... Pyrolysis in gas phase; n2, k , A.P. 1 (Bromopentane) Reaction with ammonia in aqueous solution; in, k , l(Acid) A.P. l(Amino compd.) Isothermal pyrolysis under vacuum; 400-500 ' C ; m , k , A . P . , gas-formation curve Empirical Relation between thermal decomposition and electrical conductivity; 180-227 ' C ; k , A.P. Empirical Reactivit). and adsorption properties; 950 OC; X-, specific surface ...... Reaction with dierhylamine in aqueous solution; 1 (Peroxide) 60-80 OC; m , k , A.P. 1(.4mine) Gas-phase reactions with nitric oxide; 306-59 OC, 3-71 torr and 64-436 1(Cyclohexadiene) 1 [NO) torr; m , k , A.P. Reaction with 2.4-dinitro. benzene-sulfenyl bromide in CsH6 and in CHCl3; 3 (CHCh) m, Complex (CsH6) Nitration by NzOi in CC14; -20--11.5 OC; m , i , A.P., optical density Empirical Pyrolysis by static method; 416-532 OC, initial pressure 12-30 torr, 5-600 min; m , k , A.P. 1(Cyclopentene) Hydrolysis in buflered aqueous solution; 100-25 ' C , p H 0.2-3.92; m, k 1(Phosphate) Synthesis from cocoa, ,CO, and H ; 1500-6000 PSI; m, k , A.P. Complex Reaction with anions; m, k, l(Amine) product composition 1 (Anion) Pyrolysis; 400-50 O C , 10 1(Dimethyloxetane) Iorr; m , k , A.P. Pyrolysis and reverse combination; 164-221 " C ; m , k, l(Ethoxyethy1 A.P. chloride) Hydrolysis in aqueous H2SOb; 25 OC; rn, k , activity coefficient 1(Ethylacetate) Pyrolysis; 242-60 OC; m , k , A.P. $(Ethyl nitrate)



Isobutane (273A)


Methanol (276A) (277A)

Ethylene Ethylene, ethane, propane Fluoromethane Formic acid, nitrogen dioxide (Holoalkyl) silane; Hexachlorobutadiene, octachlorobutcne, decachlorobutane Hvdrazobenzene


Methyl perchlorate (279A)

(220A) (227A)






a-Methylstyrene, tetralin, toluene, ethylbenzene Iieopentyl chloride



Iiitroacetanilide Iiitroalkanes

(224A) (2258) (226A)


A?-Nitropiperidine, .V,,V-diethylnitramine h-itrosobenzene p-Sirrotoluene, a- and p-nitrochlorobenzene

(228A) (2294)


(237A) (232A) (2334)


(235A) (236A)


(23QA) (240A) (247.4) (242A)

(243A) (244A)

(245A) (246.4)



Rraction Order with Resbcct to

Sttidy and Restilt

Pyrolysis, initiation of chains; 824 O K ; k , A.P. l(1sobutane) Condensation to produce l(1sobutene) isoprene; 0.5 ' C ; m, k , Henry coefficient 1(Formaldehyde) Xtration by various nirrating mixtures; k , reaction orders, conductance, and colorimetric data Variable Spontaneous pyrolysis inhibited by nirric oxide; 470-530 ' C ; 25-300 torr; rn, k , A.P. I(Pentene) Methanolysis in methanoldioxane and methanolacetone mixtures; m , k, A.P. 1-2 Competitive oxidation in liquid phase; 70 OC; m , k , reactivity ratio Complex Pyrolysis, molecular decompojition: 410-96 OC; m , k, A . P . 1 Pyrolvsis, radical chain decbmposition; 410-96 OC. 22-340 torr; m , k , A.P. 3/2 Hydrolysis in aqueous HzSOa; 25-90 OC; m, X-, A.P. 1 Acid-catalyzed hydrolysis; m , k , A.P. Electrochemical behavior in alkaline media; 4-33 OC, p H 10-13; m , k , A.P. 1-2 .

Xtrobenzene free radicals


Arrhenius parameters; m, mechanism. a b , rate constant; A .P,, ~~~~~~




Thermal decomposition; 400-500 OC, 4-650 torr; m , k , A.P., heat of formation 1.4-1.6 Oxidation to COn and C9Ha; k , A.P. .,.... Pyrolysis; 820-1 125 OC; rn, k , A.P. Complex Pyrolysis in flow system; 850-1100 O C ; m , k , B . P . l(F1uoromethane) Autocatalysis and deuterium isotope effects; 191.3 O C ; m, isotopic etiect on k 2 2/3 Gas phase elimination of ethylene, 300-86 O C ; m,k , A.P. 1(Silane) Chlorinolysis; 550-750 O C ; m , k, A . P . 1(Hexachlorobutadiene Noncatalyzed thermal reaction; 140-220 O C ; m , k , product composition 2(Hydrazobenzene)

Isobutene, formaldehyde


Ethyl nitrite Ethyl radical

M a j o r Reactants


Organosilicone hydrides, organic hydroperoxides n-Pentane



Pyrolvsis' 180-240 O C ; m , i;,A.P. Oxidation with H N O Bin aqueous dioxane; m , k, yield Nitration in H I S O F H N O ~ mixture; rn, k , A.P., activity coefficient Hydrolysis in aqueous HzSOd; 25 ' C ; m: k , A . P . , activity coefficient Reaction a t room temperature; 20 O C ; k , yield



Rei (2474)





(2524 (253A)

(254A) (255A) (256A) (257A)

1 (Reactant)


2 (Over-all)


1 (Aromatics)

1 (HNOd



1 (Hvdride) 1 (Hydroperoxid e ) (2624)

Thermal cracking; 540 ' C , 50-180 Torr m , k , A.P., product composition 1 (Pentane) Phenol. m-cresol Oxidation by 0 2 in aqueous medium; 25-80 OC,,pH 0 9.5-13; m , k , A . P . , yield Phthalic anhydride, Esterification in batch reactor; methanol 55-67 ' C ; k , A P. Empirical Propane Vapor-phase reaction with NOz; 200-350 'C; m , k , A.P. 2-2.35 (Overall) Propane-butane Thermal cracking; 475-570 OC, 40-240 torr, contact time 1-10 min; m, k, A . P . , yield, product composition Complex Oxidation with chromic acid 2-Propanol in acetone; m , k, Hammett constants 1 [Cr(\W] 1 (Propanol) Oxidation with .%