摘要
以HZSM-5分子筛为催化剂,在固定床反应器上进行抽余C5催化裂解制备乙烯/丙烯实验.考察了不同硅铝摩尔比的HZSM-5催化裂解抽余C5制备乙烯/丙烯的反应性能;用H3PO4浸渍法对HZSM-5进行改性,考察P改性对抽余C5催化裂解性能的影响,并采用X射线荧光光谱(XRF)、X射线衍射(XRD)、扫描电镜(SEM)、氨程序升温脱附(NH3-TPD)等手段对其进行表征.结果表明,硅铝摩尔比为50的HZSM-5具有较好的催化裂解抽余C5制乙烯/丙烯反应性能,该催化剂最适宜的工艺条件是0.1 MPa、550℃、液体质量空速为3 h-1、水/油(抽余C5)体积比为0.8;未改性HZSM-5(硅铝摩尔比为50)在最佳工艺条件下反应3 h,所得乙烯和丙烯总收率为43.43%,而P改性后的HZSM-5在相同条件下反应,乙烯和丙烯总收率可达47.30%,提高了3.87%;P改性不会破坏HZSM-5分子筛的骨架结构,可调节分子筛的酸性,改善HZSM-5分子筛的催化裂解性能.
Catalytic cracking of C5 raffinate for ethylene and propylene was investigated in a fixed bed reactor with HZSM-5 as a catalyst. The phosphorus-modified HZSM-5 was prepared and characterized by X- ray fluorescence spectrometry （XRF）, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed desorption of ammonia （ NH3-TPD）. Catalytic performance of the phosphorus-modified HZSM-5 for cracking C5 raffinate was also studied. The results showed that the catalytic performance of HZSM-5 catalyst with n（Si）/n（A1） = 50 was better than that of HZSM-5 catalysts with other n （Si）/n （A1） ratio. And the optimum reaction conditions were as follows： temperature of 550 ℃, the C5 space velocity of 3 h ^-1, the volume ratio of water/C5 of 0.8 under 0. 1 MPa. The phosphorus-modified HZSM-5 catalyst showed better catalytic performance under the optimal reaction conditions for 3 h and ethylene and propylene yield of 47.30% was obtained while ethylene and propylene yield of 43.43% was the result with HZSM-5 catalyst. The crystallinity of HZSM-5 is scarcely damaged and the phosphorus modification is an effective way to adjust the acidic properties of the HZSM-5 catalyst.
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2009年第2期30-34,共5页
Journal of Nanjing Tech University(Natural Science Edition)
基金
国家高技术研究发展计划(863计划)资助项目(2006AA020101)
关键词
抽余C5
HZSM-5
催化裂解
乙烯
丙烯
P改性
C5 raffinate
HZSM-5
catalytic cracking
ethylene
propylene
phosphorus modification
