摘要
以无机硅源、钛源和铝源为原料,采用水热合成法制备了钛硅分子筛ETS-10及铝取代的钛硅分子筛ETAS-10;借助XRD、SEM、EDX、FTIR、N2吸附-脱附和NH3-TPD技术,研究了凝胶中n(Al2O3):n(TiO2)和甲基纤维素(MC)含量对ETAS-10结晶性、结构形貌和酸性质的影响。表征结果显示,ETS-10晶体为四方切角双锥体,结晶度高而酸性弱,微孔比表面积和孔体积分别为383.75 m2/g和0.16 cm3/g。随n(Al2O3):n(TiO2)的增大,ETAS-10的结晶性和晶体尺寸同步降低,并有塔状或分离的层状聚集体形成。MC显著诱导薄层状ETAS-10晶体的形成,MC含量增至2.7%(w)时,产物以层状ETAS-10晶体为主,层间孔隙率约为0.09 cm3/g;铝嵌入骨架导致ETAS-10弱酸和中强酸量增加;受MC网状结构的限制,层状ETAS-10结晶度降低,但MC对Ti O Ti链生长取向无阻碍作用。
Titano-silicate（TS） zeolite ETS-10 and lamellar Al-substituted TS zeolite ETAS-10 were hydrothermally synthesized from sodium silicate solution, titanium sulphate and sodium aluminate, and were characterized by means of XRD, SEM, EDX, FTIR, N2 adsorption-desorption and NH3- TPD. The effects of n（A1203） ： n（TiO2） and methylcellulose（MC） concentration in initial gel mixture on the crystallinity, textural morphology and acidity of ETAS-10 were investigated. The results indicated that ETS-10 crystals were truncated square bi-pyramidal with high crystallinity, weak acidity, specific surface area 383.75 mZ/g and pore volume 0.16 cm3/g. Along with the increase of n（A1203） ： n（TiO2）, the crystallinity and mean size of ETAS-10 crystals reduced synchronously, and ETAS-10 polycrystals with spirally terraced or delaminated morphologies formed. Furthermore, the lamellar ETAS-10 crystals grew markedly due to the induction of MC addition. When the MC content in the initial gel increased to 2.7%（w）, the lamellar ETAS-10 crystals were the main product with an ＇interlamellar porosity＇ of 0.09 cma/g. The insetting of aluminum into the framework of ETAS-10 led to increasing of both the weak acidity and the moderate acidity. The lamellar ETAS-10 crystallinity lowered due to the restriction of the formed MC network. However, the lamellar crystal orientation of Ti-O-Ti chains was not be impacted by the addition of MC.
出处
《石油化工》
CAS
CSCD
北大核心
2012年第6期671-676,共6页
Petrochemical Technology
基金
辽宁省自然科学基金项目(200922180)
辽宁省高等教育科学研究协会资助项目(2009A439)
