Catalysis Today 75 (2002) 3–15 Environmental catalysis: trends and outlook G. Centi a,∗ , P. Ciambelli b,1 , S. Perathoner a , P. Russo b a Dipartimento di Chimica Industriale ed Ingegneria dei Materiali, Salita Sperone 31, 98166 Messina, Italy b Dipartimento di Ingegneria Chimica e Alimentare, Via Ponte don Melillo, 84084 Fisciano (SA), Italy Abstract Environmental catalysis has continuously grown in importance over the last 2 decades not only in terms of the worldwide catalyst market, but also as a driver of advances in the whole area of catalysis. The development of innovative “environmental” catalysts is also the crucial factor towards the objective of developing a new sustainable industrial chemistry. In the last decade, considerable expansion of the traditional area of environmental catalysis (mainly NO x removal from stationary and mobile sources, and VOC conversion) has also occurred. New areas include: (i) catalytic technologies for liquid or solid waste reduction or purification; (ii) use of catalysts in energy-efficient catalytic technologies and processes; (iii) reduction of the environmental impact in the use or disposal of catalysts; (iv) new eco-compatible refinery, chemical or non-chemical catalytic processes; (v) catalysis for greenhouse gas control; (vi) use of catalysts for user-friendly technologies and reduction of indoor pollution; (vii) catalytic processes for sustainable chemistry; (viii) reduction of the environmental impact of transport. Therefore, a significant change has occurred in the last decade in the areas of interest regarding environmental catalysts and in the modality of approaching the research. This review, based on but not limited to the workshop “Environmental Catalysis: A Step Forward” (Maiori, Italy, May 2001), introduces the proceedings of this workshop reported in this issue of Catalysis Today and has the objective of providing an overview to the topic and setting the basis for a step forward in environmental catalysis research. © 2002 Elsevier Science B.V. All rights reserved. Keywords: NO x ; Volatile organic compound; Catalysis 1. Introduction Catalysis is a key technology to provide realistic solutions to many environmental issues, but is also an important marketing opportunity. Currently the world market for catalysts is about 9 billion US $, about a third of which involves environmental catalysis. Fig. 1 shows the expectations for growth in the worldwide catalyst market through the year 2005, by general industry segment. Expectations for growth in the ∗ Corresponding author. Tel.: +39-90-676-5609; fax: +39-90-391518. E-mail addresses: gabriele.centi@unime.it, centi@unime.it (G. Centi), ciambelli@dica.unisa.it (P. Ciambelli). 1 Fax: +39-89-964-057. environmental catalysis area are indeed high. The US NIST “White Paper on Catalysis and Biocatalysis” of 1999 indicates environmental catalysis as being among the top five areas of US industry which combine tech- nology challenges and economic benefits. In addition, there are a number of critical emerging scientific plat- forms in the area of environmental catalysis which are expected to have a high inter-industry impact. Environmental catalysis refers to catalytic technolo- gies for reducing emissions of environmentally unac- ceptable compounds. Problems addressed in regard to these catalytic cleanup technologies are mobile emis- sion control, NO x removal from stationary sources, sulfur compounds and VOC (volatile organic com- pound) conversion, liquid and solid waste treatment (polymers and other solid waste), and greenhouse 0920-5861/02/$ – see front matter © 2002 Elsevier Science B.V. All rights reserved. PII:S0920-5861(02)00037-8