catalyst poison

catalyst poison

      substance that reduces the effectiveness of a catalyst in a chemical reaction. In theory, because catalysts are not consumed in chemical reactions, they can be used repeatedly over an indefinite period of time. In practice, however, poisons, which come from the reacting substances or products of the reaction itself, accumulate on the surface of solid catalysts and cause their effectiveness to decrease. For this reason, when the effectiveness of a catalyst has reached a certain low level, steps are taken to remove the poison or replenish the active catalyst component that may have reacted with the poison. Commonly encountered poisons include carbon on the silica–alumina catalyst in the cracking of petroleum; sulfur, arsenic, or lead on metal catalysts in hydrogenation or dehydrogenation reactions; and oxygen and water on iron catalysts used in ammonia synthesis.

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Universalium. 2010.

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  • каталитический яд — контактный яд — [Я.Н.Лугинский, М.С.Фези Жилинская, Ю.С.Кабиров. Англо русский словарь по электротехнике и электроэнергетике, Москва, 1999 г.] Тематики электротехника, основные понятия Синонимы контактный яд EN catalyst poisoncontact poison …   Справочник технического переводчика

  • Schwefel — Eigenschaften …   Deutsch Wikipedia

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