The role of bromine in de novo synthesis in a model fly ash system. Luijk, R.; Dorland, C.; Smit, P.; Jansen, J.; Govers, H.A.J. Published in: Chemosphere DOI:10.1016/0045-6535(94) Link to publication Citation for published version (APA):Luijk, R., Dorland, C., Smit, P., Jansen, J., & Govers, H. A. J. (1994). The role of bromine in de novo synthesis in a model fly ash system. Chemosphere, 28(7), 1299-1309. DOI: 10.1016/0045-6535(94)90074-4 General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Download date: 10 May 2018Pergamon 0045-6535(94)E0062-X Chemosphere, Vol. 28, No. 7, pp. 1299-1309, 1994 Copyright © 1994 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0045-6535/94 $7.004-0.00 THE ROLE OF BROMINE IN THE DE NOVO SYNTHESIS IN A MODEL FLY ASH SYSTEM ABSTRACTThe role of bromine in the de novo synthesis in a model fly ash system has been evaluated. A silica-alumina carrier was impregnated with a CuX7 catalyst system (X=C1, 0.5 wt%; X=Br, 0.8 wt%). A flow of air with 5 vol. % I-IX (X=C1 or Br) was passed over a fixed bed at 300°C. Several processes have been investigated concerning the role of bromine and chlorine in the formation of polyhalogenated dibenzo-p-dioxins and -dibenzofurans in municipal waste incinerator fly ash under conditions observed in an electrostatic precipitator:The exchange of bromine and chlorine in 2,3,7,8-tetrabromodibenzo-p-dioxin; The reactivity and selectivity of bromine and chlorine in the halogenation of the parent structures dibenzo-p-dioxin and dibenzofuran;The competition of bromine and chlorine in the de novo synthesis. INTRODUCTIONThe last decade several studies about the formation of polybrominated dibenzo-p-dioxins and -dibenzofurans (PBDDs and PBDFs) during thermal degradation of polymers containing brominated flame retardants have been published [1,2]. Also the presence of mixed brominate~chlorinated dibenzo-p-dioxins and -dibenzofurans (PXDDs and PXDFs with X=C1, Br) in municipal waste incinerator fly ash has been shown [3,4]. However, the analysis of PBDD/PBDFs and the mixed halogenated PXDD/PXDFs (X=CI, Br) is accompanied with difficulties. The physico-chemical properties of polybrominated compounds, i.e. high molecular weight, high melting point, low vapour pressure and low thermal stability requires a sop...

Abstract. Storms occasionally bring havoc to Northwest Europe. At present, a single storm may cause damage of up to 7 billion U.S.$, of which a substantial part is insured. One scenario of climate change indicates that storm intensity in Northwest Europe could increase by 1-9% because of the doubling of CO 2 concentrations in the atmosphere. A geographic-explicit, statistical model, based on recent storms and storm damage data for the Netherlands, shows that an increase of 2% in wind intensity by the year 2015 could lead to a 50% increase in storm damage to houses and businesses. Only 20% of the increase is due to population and economic growth. A 6% increase could even triple the damage. A simpler model -based on national average data and combined with a stochastic storm generator -shows that the average annual damage could increase by 80% with a 2% increase in wind intensity. A 6% wind intensity increase could lead to an average annual damage increase of 500%. The damage in Northwest Europe is about a factor 6 higher than the damage in the Netherlands. Little potential seems to exist for reducing the vulnerability to storms in the Netherlands. More attention should be given to planning at the government level for disaster relief and to the development of coping strategies.

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Low-level ozone pollution aects crop yields adversely. Reduction of ozone pollution would therefore increase crop yields and provide economic bene®ts to producers and consumers of farm products. This paper assesses the potential magnitude of these bene®ts for the Netherlands. Exposure±response functions were used to estimate initial yield responses when ozone pollution is reduced to natural background levels. These yield responses were fed into a spatial economic model of the Dutch farm sector, thereby allowing for demand and supply adjustments in all interrelated markets. A novelty in this analysis is the explicit attention to crop±livestock interactions. The annual economic bene®ts of ozone reduction for producers and consumers of farm products are estimated to be C = 310 million, of which C = 91 million goes to producers and C = 219 million to consumers.

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