Process to dissociate and extract the Lignin and the Xylan from the primary wall and middle lamella or lignocellulosic material which retains the structural integrity of the fibre core

A method of producing mechanically intact but separated lignocellulosic fibre cores comprising:

• (a) packing lignocellulosic material having substantially uniform lengths of heat transfer paths and being in a moist form in a pressure vessel having a valved outlet, and
• (b) with the valve closed, rapidly filling the pressure vessel with steam at a pressure of at least 130 psi to bring, by means of the pressurized steam, substantially all of the lignocellulosic material to a temperature in the range of 160 to 175 degrees celcius in less than 60 seconds and, at a temperature within said range wherein lignin and xylan components of the lignocellulosic material are softened but cellulose components of the lignocellulosic material are not softened, opening the valved outlet and instantly and explosively expelling the lignocellulosic material from the pressure vessel to cause the thermally softened lignin xylan crosslinks in the middle lamella and primary wall to be fractured while retaining the full structural integrity of the cellulose in the fibre cores.