Read me file: Yue Zhang (Y.Zhang@soton.ac.uk), Water and Environmental Engineering Group, Faculty of Engineering and the Environment, University of Southampton. The excel file contains raw experimental data for the paper: Outram V and Zhang Y (2018) Solvent-Free Membrane Extraction of Volatile Fatty Acids from Acidogenci Fermentation. Accepted on 11 September 2018. This datafile includes the data generated from the experiments listed in Table 1. 'Overview of experiments performed'. The calculation for Table 6. 'Economic analysis of membrane and extractant cost' is also provided. Date and place of data collection: 2017-18 (University of Southampton, the UK) Date that the file was created: September 2018