noun

• 1A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

  ‘chlorine acts as a catalyst promoting the breakdown of ozone’

  More example sentences

  • ‘The key tools will be new breeds of enzymes - protein catalysts that speed up chemical reactions in cells.’
  • ‘Most converters use platinum or palladium metal catalysts that convert carbon monoxide and hydrocarbons to carbon dioxide and water vapor.’
  • ‘Heterogeneous catalysts are materials that increase the rate of a reaction, but are not in the same phase as the reactants.’
  • ‘All of the platinum-group metals are good catalysts: they speed up the rate of certain chemical reactions.’
  • ‘These versatile molecules function as catalysts in the hydrogen peroxide bleaching process.’
  • ‘Catalyst recovery is one of the most actively researched areas for cost-cutting in the chemical industry, as catalysts often contain rare and expensive metals.’
  • ‘When temperature is increased, synthetic catalysts can become just as active as enzymes.’
  • ‘Solid oxide catalysts are commonly used for chemical and refinery operations.’
  • ‘Enzymes are the biological substance that act as catalysts and help complex reactions occur everywhere in life.’
  • ‘He attempted to polymerize ethylene using catalysts at a much lower pressure than that used by the British process.’
  • ‘Instead, we started to look further afield at copper-based catalysts that had been rejected during the initial ester hydrogenation testwork.’
  • ‘Finally, a relatively small amount of rhenium is used to make catalysts for the petroleum industry.’
  • ‘The one exception is that it is sometimes used as a catalyst in the petroleum industry.’
  • ‘Chemicals in the catalytic converter act as catalysts, changing the highly hazardous gas compounds to less harmful ones.’
  • ‘The element is also used to make dyes, photographic film, specialized soaps, and catalysts.’
  • ‘Some germanium is also used to make semiconductors, catalysts, and specialized glass for military weapon-sighting systems.’
  • ‘Many alkyl halides, alcohols, or alkenes can be reacted with benzene in the presence of certain catalysts to give an alkyl benzene.’
  • ‘Silicone surfactants, and amine and tin catalysts, are also used.’
  • ‘Ionic liquids usefully form one of the phases because they don't mix with many organic solvents, but readily dissolve metals used as catalysts.’
  • ‘In fact, zeolites are the main catalysts in petrochemical refineries today.’

  Synonyms

  channel, medium, means, means of expression, agency, agent, instrument, mechanism, organ, apparatus, structure, machine, machinery

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  1. 1.1A person or thing that precipitates an event.
     ‘the governor's speech acted as a catalyst for debate’
     More example sentences

     • ‘Though the film is around these two men, it is the women who play the catalyst to all the events and add momentum to the story.’
     • ‘It is the union of the latter two that provides the catalyst for the events that follow.’
     • ‘In Scotland, it has always been Catholic schools which have been the catalyst for this debate.’
     • ‘It will hopefully act as a catalyst for more formal public education in the future.’
     • ‘It is amazing what acts as a catalyst to spur people on to do something about a situation.’
     • ‘Historical and meaningful events such as this often act as a catalyst for change.’
     • ‘The film's other characters are secondary, and often serve little purpose beyond acting as catalysts.’
     • ‘More importantly, it was about inspired individuals being the catalysts of effecting new possibilities.’
     • ‘The beach becomes the catalyst which encourages them to break society's rules.’
     • ‘Public opinion polls often serve as catalysts for such debates.’
     • ‘I hope that it will be a catalyst for an ongoing debate and discussion in our field.’
     • ‘Events, individuals, circumstances and situations are catalysts for transformations in culture.’
     • ‘There are many events however that serve as catalysts for the big historic shifts.’
     • ‘This is the catalyst for a chain of events which threatens to destabilise the parliament.’
     • ‘The event was to be used as a catalyst for change and to bring new hope to residents in rundown areas of the city.’
     • ‘The primary catalysts that induced this growth were the end-user industries, communications, and computers, in particular.’
     • ‘On the second issue, the crisis also served as a catalyst to the birth of a more responsible and braver press.’
     • ‘All three shocks have caused, or been a catalyst for, a serious downturn in western economies.’
     • ‘The Parliamentary debate on this report was the actual catalyst which prompted the minister to resign.’
     • ‘If there is any catalyst to get the team motivated for next season it will be this performance in the nationals.’
     Synonyms

     spur, stimulus, impetus, prompt, encouragement, inducement, incitement, prompt

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