The research behind this dataset revolves around the electrochemical conversion of CO2 at ambient conditions, using a novel copper based tubular electrode. Main reaction of interest is the formation of CO from CO2. This particular dataset involves the study of the effect of co-feeding CO and CO2 on the CO2 conversion rate of the tubular porous electrodes. Chronoamperometry experiments are performed at -1.1 V vs Ag/AgCl while purging the gaseous reactant through the porous catalyst wall. A Zirfon anion exchange membrane is used to separate the catholyte and anolyte (both 0.3 M KHCO3). A platinum on titanium mesh is used as counter electrode. The dataset supplements to the next publication: ‘Conversion of a CO-CO2 co-feed with a porous tubular copper catalyst at low potential’