蜡油加氢处理催化剂失活原因分析及再生性能考察

DEACTIVATION ANALYSIS AND REGENERATION PERFORMANCE OF VACUUM GAS OIL HYDROFINING CATALYST

对某炼油厂蜡油加氢装置中反应器上床层出现明显失活现象的催化剂进行了失活原因分析和再生性能考察。分别对甲苯抽提后的失活催化剂及再生处理后的催化剂,采用X射线荧光光谱、N 2吸附-脱附和X射线光电子能谱等手段进行检测。结果表明:失活催化剂的比表面积和孔体积明显降低,再生催化剂的孔体积明显恢复,而比表面积未恢复;失活催化剂上积炭较少,在再生过程中易分解,因而不会导致催化剂孔结构性质发生较大变化;催化剂表面沉积含P,Fe,Si元素的无机物,堵塞催化剂孔道或沉积在催化剂孔道是其失活的主要原因。相比于新鲜催化剂,失活催化剂基本无催化活性,而再生催化剂虽表现出一定的初活性,但活性急剧下降,因而催化剂的失活为永久性失活。

Deactivation analysis and regeneration performance investigation were carried out on the catalyst which appeared obvious deactivation in the first catalyst bed of the reactor in a vacuum gas oil hydrofining unit of a refinery.The fresh catalyst,deactivated catalyst after toluene extraction and the regenerated catalyst were detected by means of X-ray fluorescence spectrometer(XRF),specific surface area and aperture analyzer,and X-ray photoelectron spectroscopy(XPS).The results showed that the specific surface area and pore volume of the deactivated catalyst decreased obviously,and the pore volume of regenerated catalyst was obviously recovered,but the specific surface area was not recovered completely.The main reason for the deactivation of the catalyst was that the inorganic materials containing P,Fe and Si elements were deposited on the surface of the catalyst,which blocked or deposited in the catalyst channel.Compared with the fresh catalyst,the deactivated catalyst had no catalytic activity,and the regenerated catalyst showed some initial activity,but the activity dropped sharply,so the deactivated catalyst was permanently deactivated.