摘要
采用水热晶化法,通过调变投料配比,制备出了具有相同晶貌且含有介孔结构的不同硅铝比的ZSM-5分子筛,采用X射线衍射(XRD)、X射线荧光光谱(XRF)、扫描电镜(SEM)、N_(2)物理吸附-脱附、氨气程序升温脱附(NH_(3)-TPD)等手段对其进行表征,在连续固定床微反装置上进行了丁烯催化裂解反应性能评价。研究结果表明,随着ZSM-5分子筛硅铝比的增加,晶粒尺寸逐渐由10μm缩小至2μm,硅铝比由78增加至462,酸量由0.925 mmol/g逐渐降低至0.035 3 mmol/g。随着硅铝比的增加,丁烯转化率逐渐降低,丙烯选择性逐渐增加,重组分选择性逐渐降低。较强的催化剂酸性会导致过多副反应的发生,降低目标产物的选择性和收率,硅铝比为263的ZSM-5分子筛在丁烯裂解反应中具有较高的丙烯选择性和催化稳定性,丁烯转化率为74%左右,丙烯选择性为48%,丙烯收率为35.5%。
A series of ZSM-5 molecular sieves with different Si/Al ratios but the same crystal morphology and containing mesoporous structure are prepared through the hydrothermal crystallization method by adjusting the feed ratio.The samples are characterized by using techniques such as X-ray diffraction(XRD),X-ray fluorescence spectroscopy(XRF),scanning electron microscopy(SEM),N_(2) adsorption-desorption,and ammonia temperature-programmed desorption(NH_(3)-TPD).The catalytic performance of the prepared ZSM-5 molecular sieves for butene cracking reaction is evaluated in a continuous fixed-bed micro-reactor.Study results show that as Si/Al ratio of ZSM-5 molecular sieves increases,the crystal grain size decreases from 10μm to 2μm gradually.As the Si/Al ratio increases from 78 to 462,the acid amount of the molecular sieves decreases from 0.925 mmol/g to 0.0353 mmol/g.With the increasing Si/Al ratio,the conversion rate of butene decreases gradually,the selectivity of propylene rises gradually,and the selectivity of heavy products declines gradually.Stronger acidity of the catalyst leads to excessive side reactions,thus reducing the selectivity and yield of the target product.The ZSM-5 molecular sieve with a Si/Al ratio of 263 exhibits high propylene selectivity and catalytic stability in the butene cracking reaction,delivering a butene conversion rate of around 74%,a propylene selectivity of 48%,and a propylene yield of 35.5%.
作者
郭栋
童燕兵
柯明
GUO Dong;TONG Yan-bing;KE Ming(Shandong Sunway Chemical Group Co.,Ltd.,Zibo 255434,China;College of Science,China University of Petroleum-Beijing,Beijing 102249,China)
出处
《现代化工》
北大核心
2025年第7期144-150,共7页
Modern Chemical Industry
基金
国家自然科学基金(21776505)。
作者简介
郭栋(1981-),男,硕士,高级工程师,主要从事炼油工艺开发及设计,guodong@sdsunway.com.cn。;通讯联系人:柯明(1963-),男,教授,研究方向为清洁油品生产,keming@cup.edu.cn。
