A process for reaction and separation which comprises inputting a process material into at least one column of a plurality of columns wherein each column has at least one inlet for accepting flow from another column or group of columns, an external feed stream, an external eluent stream or a combination thereof, and each column has at least one outlet for connecting to another column, a group of columns, an external product stream or a combination thereof. Each column is independently operable in an up-flow or down-flow mode and connected independently to one of the group comprising another column, an external feed stream, an external eluent stream, an external product stream and combinations thereof.