an integral structure is provided for chemical processing and manufacture , in which a plurality of laminae are joined together and having inlet and outlet ports connected by a three dimensionally tortuous channel . chemicals are introduced through the inlet ports and processed along the channel , with desirable product withdrawn through the outlet ports . the laminae are of materials selected to be compatible with the chemical process , from the group consisting of elements of groups iii , iv or v of the periodic table , ceramics , glasses , polymers , composites and metals . processes of manufacture of the apparatus and processes utilizing the apparatus are also disclosed herein .