B.E.T surface area???

WASIM

Hello every one;

I need your help. Can anybody tell me the physical meaning of B.E.T surface area??

A catalyst is loaded on a 300x3291 (micro-meter) wall.The given properties of the catalyst are; catalyst density(kg/m^3)=2400, Catalyst pore mean radius(m)=8x10^-9, BET area(m^2/g)=66 ,Void fraction=0.47, Partical size(mm)=0.3-0.425.

How I can find the real surface area???

waiting EAGERLY FOR YOUR HELP

WASIM