Журнал Сибирского федерального университета. Химия. Journal of Siberian Federal University/ Chemistry №4 2008

Стр.1

Стр.2

Стр.3

Журнал Сибирского федерального университета Journal of Siberian Federal University Химия Chemistry Редакционный совет академик РАН Е.А.Ваганов академик РАН К.С.Александров академик РАН И.И.Гительзон академик РАН В.Ф.Шабанов чл.-к. РАН, д-р физ.-мат.наук А.Г.Дегерменджи чл.-к. РАН, д-р физ.-мат. наук В.Л.Миронов чл.-к. РАН, д-р техн. наук Г.Л.Пашков чл.-к. РАН, д-р физ.-мат. наук В.В.Шайдуров чл.-к. РАО, д-р физ.-мат. наук В.С. Соколов Editorial Advisory Board Chairman: Eugene A. Vaganov Members: Kirill S. Alexandrov Josef J. Gitelzon Vasily F. Shabanov Andrey G. Degermendzhy Valery L. Mironov Gennady L. Pashkov Vladimir V. Shaidurov Veniamin S. Sokolov Editorial Board: Editor-in-Chief: Mikhail I. Gladyshev Founding Editor: Vladimir I. Kolmakov Managing Editor: Olga F. Alexandrova Executive Editor for Chemistry: Boris N. Kuznetsov Редактор И.А. Вейсиг Корректор Т.Е. Бастрыгина Компьютерная верстка И.В. Гревцовой, Е.В. Гревцовой Подписано в печать 22.12.2008 г. Формат 19х27. Усл. печ. л. 6,6. Уч.-изд. л. 10,5. Бумага тип. Печать офсетная. Тираж 1000 экз. Заказ 1/215. Отпечатано в ИПК СФУ. 660041 Красноярск, пр. Свободный, 79. CONTENTS / СОДЕРЖАНИЕ Dmitry V. Kazachkin, David R. Luebke, Vladimir I. Kovalchuk, and Julie L. d’Itri Hydrogen-Assisted 1,2-Dichloroethane Dechlorination Catalyzed by Pt-Cu/SiO2 Active Sites : Insights into the Nature of Ethylene-Selective – 303 – Alexey N. Lukianov, Olga N. Kononova and Sergey V. Kachin Calculation of Protolytic Equilibria Parameters on a Surface of Some Carbon Adsorbents According to Potentiometric Titration Data – 326 – Tatiana G. Shendrik, Valentina V. Siminova, Nikolai V. Chesnokov and Boris N. Kuznetsov Properties of Active Carbons Produced by Thermochemical Transformation of Lignin, Brown Coal and Oil Slime Mixtures – 336 – Anatoly I. Rubailo and Andrey V. Oberenko Polycyclic Aromatic Hydrocarbons as Priority Pollutants – 344 – Irina G. Sudakova, Boris N. Kuznetsov, Natalia V. Garyntseva, Nina I. Pavlenko and Natalia M. Ivanchenko Functional and Thermal Analysis of Suberin Isolated from Birch Bark – 355 – 2008 1 (4)

Стр.1

Editorial board for Chemistry: Nikolai V. Chesnokov Lubov ’ K. Altunina Natalia G. Bazarnova Vasiliy A. Babkin Vicente Cebolla Viktor M. Denisov Zinfer R. Ismagilov Sergey V. Kachin Sergey D. Kirik Wolfgang Klose Vladimir I. Kovalchuk Vladimir A. Likholobov Yuri L. Mikhlin Gennady L. Pashkov Anatoly I. Rubailo Tatyana V. Ryazanova Vladimir A. Sobyanin Valeri E. Tarabanko Tatyana G. Shendrik Maxim L. Shchipko Jean V. Weber Valeri E. Tarabanko, Olga A. Ulyanova, Galina S. Kalachova, Valentina V. Chuprova and Nikolai V. Tarabanko Study of Plant Growth Promoting Activity and Chemical Composition of Pine Bark after Various Storage Periods – 363 – Владимир А. Левданский, Александр В. Левданский, Борис Н. Кузнецов Влияние ортофосфорной кислоты на химические превращения бетулинола в бутаноле, изобутаноле и уксусной кислоте – 369 – Светлана А. Козлова, Владимир А. Парфенов, Людмила С. Тарасова, Сергей Д. Кирик Состояние силанольного покрытия мезоструктурированного силикатного материала МСМ-41 в результате постсинтетической активации – 376 – Светлана И. Цыганова, Александр Н. Швецов, Ирина В. Королькова, Николай В. Чесноков, Борис Н. Кузнецов Влияние модифицирующих добавок на карбонизацию смесей березовых опилок с каменноугольным пеком Свидетельство о регистрации СМИ ПИ № ФС77-28-726 от 29.06.2007 г. – 389 – Светлана А. Быстрякова, Людмила П. Рубчевская Состав фосфолипидов хвои сосны сибирской – 399 – Правила представления статей для публикации – 405 –

Стр.2

Journal of Siberian Federal University. Chemistry 4 (2008 1) 303-325 ~ ~ ~ УДК 546 Hydrogen-Assisted 1,2-Dichloroethane Dechlorination Catalyzed by Pt-Cu/SiO2 : Insights into the Nature of Ethylene-Selective Active Sites Dmitry V. Kazachkin, David R. Luebke, Vladimir I. Kovalchuk* and Julie L. d’Itri Department of Chemical Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 1 Received 24.11.2008, received in revised form 15.12.2008, accepted 22.12.2008 Differently pretreated silica-supported Pt, Cu, and Pt-Cu catalysts with Cu to Pt atomic ratio of 1 to 6 have been investigated by a combination of reaction kinetics and FTIR spectroscopic studies in order to understand the factors that control the selectivity toward ethylene and ethane in the CH2 ClCH2 Cl+H2 reaction. Carbon monoxide adsorption was used to probe the electronic modification of Pt and Cu as well as the nature of ethylene-selective active sites. It was shown that there is a very limited, if any, electronic interaction between Pt and Cu in the bimetallic catalysts reduced at 493 K. However, the Pt-Cu catalysts, for which no dipole-dipole coupling shift was observed in the IR spectra of adsorbed CO suggesting extremely small Pt ensembles on the catalyst surface, demonstrated high ethylene selectivity in the 1,2-dichloroethane dechlorination. Electronic interactions between Pt and Cu have been discovered for the Pt-Cu/SiO2 by a higher stability of Cu0 in the FTIR spectra of adsorbed CO. The initial ethylene selectivity of the catalysts was inversely proportional to the dipole-dipole coupling shift. The observations are consistent with the idea that the nature of the Pt-Cu species, viz., alloy particles as opposed to Cu/Pt overlayers, does not control the reaction selectivity, which is a function of the Pt ensemble size on the surface of Pt-Cu moieties. Keywords: hydrogen-assisted dechlorination, 1,2-dichlorothane, ethylene, Pt-Cu catalysts, infrared spectroscopy, singleton frequency, dipole-dipole coupling. Introduction It has been discovered a decade ago that a combination of Pt or Pd with another metal deposited on a solid support catalyzes hydrodechlorination of vicinal dichloroalkanes such as 1,2-dichloroethane and 1,2© Siberian Federal University. All rights reserved dichloropropane toward the formation of the corresponding alkene, viz., ethylene or propylene [1-3]. Such a chemistry looks surprising because any catalyst that activates H2 catalysts reduced at 773 K. The interactions manifested themselves -CO adsorption complexes in vacuum and by an increase in intensity of the Pt-CO band in the FTIR spectra upon evacuation of CO from the gas phase suggesting the formation of Pt-Cu solid solutions. The higher temperature reduction resulted in the dipole-dipole coupling shift of 6 to 19 cm-1 should also hydrogenate the product olefin. As chloroalkanes are common environmental pollutants and alkenes * Corresponding author E-mail address: vkovalchuk@mckasd.net 1 – 303 –

Стр.3