Volume 200, 2017

Ambient and laboratory observations of organic ammonium salts in PM1

Abstract

Ambient measurements of PM1 aerosol chemical composition at Cabauw, the Netherlands, implicate higher ammonium concentrations than explained by the formation of inorganic ammonium salts. This additional particulate ammonium is called excess ammonium (eNH4). Height profiles over the Cabauw Experimental Site for Atmospheric Research (CESAR) tower, of combined ground based and airborne aerosol mass spectrometric (AMS) measurements on a Zeppelin airship show higher concentrations of eNH4 at higher altitudes compared to the ground. Through flights across the Netherlands, the Zeppelin based measurements furthermore substantiate eNH4 as a regional phenomenon in the planetary boundary layer. The excess ammonium correlates with mass spectral signatures of (di-)carboxylic acids, making a heterogeneous acid–base reaction the likely process of NH3 uptake. We show that this excess ammonium was neutralized by the organic fraction forming particulate organic ammonium salts. We discuss the significance of such organic ammonium salts for atmospheric aerosols and suggest that NH3 emission control will have benefits for particulate matter control beyond the reduction of inorganic ammonium salts.

Associated articles

Supplementary files

Article information

Article type
Paper
Submitted
20 ⵉⵏⵏ 2017
Accepted
10 ⴱⵕⴰ 2017
First published
05 ⵢⵓⵏ 2017

Faraday Discuss., 2017,200, 331-351

Ambient and laboratory observations of organic ammonium salts in PM1

P. Schlag, F. Rubach, T. F. Mentel, D. Reimer, F. Canonaco, J. S. Henzing, M. Moerman, R. Otjes, A. S. H. Prévôt, F. Rohrer, B. Rosati, R. Tillmann, E. Weingartner and A. Kiendler-Scharr, Faraday Discuss., 2017, 200, 331 DOI: 10.1039/C7FD00027H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements