镓改性纳米HZSM-5分子筛催化剂的丁烷芳构化反应

Butane aromatization of Ga modified nano HZSM-5 zeolite catalysts

以硝酸镓为浸渍液,采用等体积浸渍法制备了镓改性HZSM-5分子筛催化剂;然后,分别以正丁烷和异丁烷为原料,在反应温度为550℃,反应压力为1.0 MPa,空速为1.0 h^(-1)的条件下,考察了负载Ga离子质量分数对催化剂芳构化反应性能的影响。结果表明:以异丁烷为原料,当负载Ga离子质量分数为1.0%时,转化率和芳烃选择性均达到最大值,二者分别为98.86%,47.35%;以正丁烷为原料时,采用负载Ga离子质量分数为0.1%的改性催化剂,转化率和芳烃选择性较未改性者均有所提高,分别为87.29%,48.43%;Ga离子的引入可调变纳米HZSM-5分子筛催化剂的酸性,提高丁烷芳构化的转化率与选择性。

The gallium(Ga)modified nano HZSM-5 zeolite catalysts were prepared by equal volume impregnation method with gallium nitrate as impregnation liquid;then,the effects of Ga ion mass fraction on the aromatization reaction properties of catalysts were investigated with n-butane and iso-butane as raw materials at reaction temperature of 550℃,reaction pressure of 1.0 MPa,and space velocity of 1.0 h^(-1).The results showed that when the mass fraction of impregnated Ga ion was 1.0%and using iso-butane as raw material,the conversion rate and aromatics selectivity had reached maximum at 98.86%and 47.35%respectively;for n-butane as raw material,the mass fraction of impregnated Ga ion was 0.1%,compared with the unmodified catalyst,the conversion rate and aromatics selectivity of modified catalyst were up to 87.29%and 48.43%respectively.The acidity of nano HZSM-5 zeolite catalyst was changed by introduction of Ga ion,which improved the conversion rate and selectivity of butane aromatization.