An apparatus including at least one electrolytic cell having at least one electrode compartment structured to contain a liquid electrolyte and a plurality of electrically conducting particulates forming a particulate bed, at least one reaction region structured to support electrochemical reactions, at least one collection region structured to facilitate collection of electrically conducting particulates, at least one feeding region structured to facilitate input of electrically conducting particulates, at least one actuation module arranged substantially outside of the at least one reaction region of relevance for the electrochemical modifications.