ZnO/Cu改性Al_2O_3对FCC汽油选择性加氢脱硫性能的影响

EFFECT OF ALUMINA MODIFIED BY ZnO/Cu ON THE SELECTIVE HYDRODESULFURIZATION OF FCC NAPHTHA

以全馏分催化裂化汽油为原料,考察ZnO/Cu改性γ-Al_2O_3的选择性加氢脱硫性能。结果表明,ZnO、Cu双组分改性可进一步提高ZnO单组分改性后γ-Al_2O_3的加氢脱硫选择性。所研制的催化剂具有良好的稳定性,在1000 h实验过程中,含10%ZnO和1%Cu的催化剂的脱硫率可维持在75.0%～80.0%,液体收率为85.0%,加氢脱硫后汽油研究法辛烷值(RON)与原料相比降低1.3个单位。通过XRD、NH_3-TPD、H_2-TPR及吡啶脱附FT-IR对催化剂进行表征,结果表明可能是由于Cu的引入提高了催化剂活化氢的能力,同时形成了较弱的酸中心,从而提高催化剂的脱硫选择性。

The selective hydrodesulfurization （HDS） performance of γ-alumina modified by ZnO and Cu was investigated using full-range FCC naphtha as feedstock. Test results showed that as compared with γ-alumina modified by single ZnO, the HDS selectivity of γ-alumina could be further improved by dual-component （ZnO and Cu） modification. During a 1 000 h long-run test, using a catalyst containing 10% ZnO and 1% Cu, the sulfur removal rate could be maintained at 75.0%- 80.0% and with a liquid yield of 80.0%, which indicated that the catalyst possessed excellent stability. However, the RON of the treated naphtha was 1.3 units lower than that of the feedstock. The prepared catalysts were charac terized by XRD, NH3-TPD, H2-TPR and pyridine desorption FT-IR. It seems that the incorporation of Cu could help the catalyst to activate hydrogen and form weak acid sites simultaneously, thus the HDS selectivity of the catalyst was improved.