Date of Award

Fall 1997

Document Type

Thesis

Degree Name

Master of Science in Applied Chemistry - (M.S.)

Department

Chemical Engineering, Chemistry and Environmental Science

First Advisor

Joseph W. Bozzelli

Second Advisor

Carol A. Venanzi

Third Advisor

Barbara B. Kebbekus

Abstract

Thermodynamic properties, ΔHf°298, S°298 and Cp(T) 300≤T/K≤1500, for C1, C2 chlorocarbons are calculated by AM1 and PM3 in MOPAC6, then compared with the literature data. AM1- and PM3-derived S°298 and Cp(T) (300≤T/K≤1500) are found to be consistent with the literature (Rd ≤ ± 5%). ΔHf°298 of CH2Cl2, CH2ClCH2Cl, CH2ClCHCl2, CHCl2CHCl2, and C2Cl4 and C2Cl2 calculated by PM3 as well as ΔHf°298 of CCl4, C2HCl3, C2Cl4 and C2Cl2 by AM1 have more than ± 5 kcal/mol deviations. A Modified Group Additivity method is shown to be precise when compared with the literature.

A complete reaction system consisting of 12 elementary reaction and 19 species has been developed to model the reaction system of OH + C2H3Cl. There are two different carbon sites where addition can occur, α-addition and β-addition, as well as two different abstractions, α-abstraction and β-abstraction. Thermochemical kinetic parameters are developed for each elementary reaction and a chemical activation kinetic analysis using Multi-frequency QRRK theory for k(E) and modified strong collision approach for fall-off is used to calculate k's as function of pressure and temperature. Thermodynamic parameters are determined by MOPAC6/PM3 and the Group Additivity estimation. We are trying to use ab initio and density function methods at different levels to calculate the addition reactants, products and the transition states. All reactions in the mechanism incorporate reverse reaction rates calculated from thermodynamic parameters and Microscopic Reversibility. Results show good agreement with several experimental data. Recommended rate constants for the primary addition channels at 760 torr are: k(OH + C2H3Cl --> CH2OHC.HCl) = 4.22x1030 x T-5.88e4837/RT cm3mol-1sec-1k(OH + C2H3Cl --> Cl + CH2CHOH) = 8.61x1012 x T0.01e4114/RT cm3mol-1sec-1.

Included in

Chemistry Commons

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