Future NOx regulations for diesel engines beyond the 1994/5 USA and EEC regulations, such as the 2.5 g/BhpHr California regulations of 1998, are very difficult to meet through engine design changes. Although a large effort is being placed into deNOx catalyst research, and some research into translating power station SCR technology to diesel engines has been undertaken, there has been relatively little research into non-catalytic deNOx. This paper reviews the problems in the catalytic techniques and the possibilities of chemical deNOx. Existing flow reactor results are shown to be sufficiently encouraging to warrant applications on diesel engines. Ammonia and related liquid chemicals are shown to give effective NOx reduction at temperatures around 1000C. The light off temperature of these reactions is reduced by the presence of hydrocarbons and excess oxygen, both of which are present in diesel exhausts. Light off temperatures as low as 700C have been demonstrated using hydrogen peroxide/ammonia and as low as 500C by using amines, which gives the possibility of diesel exhaust port injection of deNOx chemicals. The economics of deNOx chemicals is shown to be favourable at less than 1% of the fuel costs and 0.5% of the fuel flow rate. For the covering abstract see IRRD 873243.


  • English

Media Info

  • Features: References;
  • Pagination: p. 137-54

Subject/Index Terms

Filing Info

  • Accession Number: 00713390
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • ISBN: 0-85298-847-8
  • Files: ITRD
  • Created Date: Nov 22 1995 12:00AM