While BET theory is highly useful, it has its limitations:
It is most accurate for relative pressures in the range of 0.05 to 0.35. Outside this range, deviations can occur. The theory assumes a homogeneous surface, which may not be true for all catalysts. It does not account for microporosity effectively, making it less suitable for materials with very small pores.
Despite these limitations, BET theory remains a cornerstone in the characterization of catalysts.
