富B酸复合材料的制备及其在重油FCC催化剂中的应用

以偏铝酸钠抽提高岭土产生的硅为硅源、偏铝酸钠为铝源、十六烷基三甲基溴化铵为模板剂,利用模板组装原理在高岭土结构中原位构筑了有序介孔硅铝结构单元,制备了富B酸有序介孔硅铝/高岭土复合材料;采用XRD、N_2吸附-脱附和吡啶吸附红外光谱对所制备复合材料进行表征。结果表明,制备复合材料比表面积可达253m~2/g,孔体积可达0.43cm~3/g,具有丰富的表面B酸中心;作为基质材料,所制备复合材料不但显著提高了催化裂化催化剂的重油转化能力,并显著改善了裂化产品的选择性,可使转化率提高3.19百分点,同时使汽油和总液体收率分别提高2.95和2.47百分点,重油和焦炭收率分别下降2.12和0.41百分点。

PREPARATION OF COMPOSITE MATERIAL RICH IN BRONSTED ACID AND ITS APPLICATION IN RFCC CATALYST

Ordered mesoporous silica-alumina/kaolin composite rich in Bronsted acid was prepared in situ within kaolin clay by template assembly method, using the silica extracted from kaolin by NaAlO2 as a silica source, NaAlO2 as aluminum source, CTAB as template. The composite materials were characterized by XRD, N2 adsorption and pyridine adsorption FT-IR. Characterization results indicate that the surface area and pore volume of obtained composite material is up to 253 m2/g and 0.43 mL/g, respectively with abundant surface B acid sites. Heavy oil cracking results confirm the significant improvement in conversion and selectivity of the FCC catalyst using the composite material as matrix. The yield of gasoline and total liquid increases by 2.95 and 2.47 percentage points, respectively and the conversion rises by 3.19 percentage points, while the heavy oil and coke decreases by 2.12 and 0.41 percentage points, respectively.