Ti－SiPentasil沸石的孔分布、比表面、吸附性能及表面酸性的考察

Ｎ＿２吸附等温线及ＢＪＨ脱附孔分布结果表明：当钛含量合适时，所合成的Ｔｉ－Ｓｉ沸石具有非常均匀的孔结构。ＴＳ－１沸石（ＺＳＭ—５型）的ＢＥＴ表面积为３８６—４２３ｍ￣２／ｇ，ＴＳ－２沸石（ＺＳＭ－１１型）的ＢＥＴ表面积为３５５—４５６ｍ￣２／ｇ，且均随合成沸石中钛含量增加而呈下降的趋势。吸附结果表明Ｔｉ－Ｓｉ沸石均有明显的疏水性，其正己烷的吸附量明显高于环己烷，随钛含量不同而发生变化，但其Ｈ＿２Ｏ＿２的吸附量却随钛含量增加而显著增大。ＮＨ＿３—ＴＰＤ试验表明，Ｔｉ－Ｓｉ沸石表面酸性相当弱，根本不存在强酸中心。

Investigation of Pore Distribution,BET Surface Area,Sorption Properties and Surface Acidity of Ti-Si Pentasil Zeolites

The results Of N_2 adsorption isotherm plots and BJH desorption pore distribution curvesshowed that Ti-Si zeolites synthesized had very homogeneous pore structure when titanium content was suitable. BET surface area of TS-1 zeolites was from 386 to 423m￣2/g,that of TS-2 zeo-lites was from 355 to 456m￣2/g,and they gradually reduced with increasing titanium content.Adsorption data revealed that Ti-Si zeolites possessed hydrophobic characteristics,and sorption capacity of n-hexane on Ti-Si zeolites was larger than that of cyclohexane;however,sorption capaci-ty of H_2O_2 increased continuously with increasing titanium content. NH_3-TPD tests confirmed thatsurface acidity of Ti-Si zeolites was very weak,with absence of strong acidic sites.