1. Department of Fossil Fuels and Environmental Geochemistry (Postgraduate Institute), NRG, Drummond Building, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, United Kingdom; Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow G1 1XL, United Kingdom; and School of Chemical, Environmental and Mining Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom