Different from conventional reservoirs, fluid percolation in tight reservoirs does not conform to the classic Darcy's law, but has both dynamic starting pressure gradient and stress sensitive effect. The JBN method don't take these two factors into account when calculating relative permeability, which is bound to cause calculation errors. The seepage mechanism of tight gas reservoir was analyze, then a two phase seepage calculation method was built and verified considering the dynamic threshold pressure gradient and stress effect. The results show that when consider the dynamic threshold pressure gradient and stress effect, the seepage ability of gas and water phase both decrease obviously, and the decrease degree of water is bigger than the gas phase. The isotonic point of relative permeability decreases and the residue water saturation increases in rock sample. With the decline of pore pressure, the effect of dynamic threshold pressure gradient and stress becomes more and more significant. The new relative permeability curves calculated by the new method is more different with the curves calculated by the JBN method. The new method can describe the seepage of fluid in tight formation more accuracy.

Fe ₂(SO ₄) ₃/bentonite solid acid catalyst was prepared, which the bentonite was disposed using H ₂SO ₄ and the catalyst carriers dipped with Fe ₂(SO ₄) ₃ solution. The influence of H ₂SO ₄ mass fraction, Fe ₂(SO ₄) ₃ concentration and activation temperature on the Fe-B/SO ₄ ^2- catalytic performances through isopropylation reaction of naphthalene was investigated. The suitable preparing technology conditions were obtained as follows: H ₂SO ₄  mass fraction is 10%, Fe ₂(SO ₄) ₃ concentration is 0.08 mol/L and activation temperature is 200 ℃. Meanwhile, the Fe ₂(SO ₄) ₃/bentonite catalyst was characterized by XRD, BET, TG and SEM methods, respectively.