Process for selectively producing C3 olefins in a fluid catalytic cracking process with recycle of a C4 fraction to a secondary reaction zone separate from a dense bed stripping zone
    1.
    发明授权
    Process for selectively producing C3 olefins in a fluid catalytic cracking process with recycle of a C4 fraction to a secondary reaction zone separate from a dense bed stripping zone 失效
    在流化催化裂化过程中选择性生产C3烯烃的方法,其中将C4馏分再循环到与致密床层汽提区分开的第二反应区

    公开(公告)号:US07374660B2

    公开(公告)日:2008-05-20

    申请号:US10993057

    申请日:2004-11-19

    摘要: A process for selectively producing C3 olefins from a catalytically cracked or thermally cracked naphtha stream is disclosed herein. The naphtha stream is introduced into a process unit comprised of a reaction zone, a stripping zone containing a dense phase, a catalyst regeneration zone, and a fractionation zone. The naphtha feedstream is contacted in the reaction zone with a catalyst containing from about 10 to about 50 wt. % of a crystalline zeolite having an average pore diameter less than about 0.7 nanometers at reaction conditions. Vapor products are collected overhead and the catalyst particles are passed through the stripping zone on the way to the catalyst regeneration zone. Volatiles are stripped with steam in the stripping zone and the catalyst particles are sent to the catalyst regeneration zone where coke is burned from the catalyst, and are then recycled to the reaction zone. Overhead products from the reaction zone are passed to a fractionation zone where a stream of C3 products is recovered and a stream rich in C4 olefins is recycled to a dilute phase reaction zone in the stripping zone separate from the dense phase of the stripping zone. The olefins can be further processed and polymerized to form a variety of polymer materials.

    摘要翻译: 本文公开了从催化裂化或热裂解的石脑油流中选择性地生产C 3 O 3烯烃的方法。 将石脑油流引入由反应区,含有密相的汽提区,催化剂再生区和分馏区组成的工艺单元中。 石脑油原料流在反应区中与含有约10至约50wt。 %的平均孔径在反应条件下小于约0.7纳米的结晶沸石。 蒸气产物被顶部收集,催化剂颗粒在通向催化剂再生区的途中通过汽提区。 挥发物在汽提区中用蒸汽汽提,催化剂颗粒被送到催化剂再生区,在该区域,焦炭从催化剂中燃烧,然后再循环到反应区。 将来自反应区的开销产物通入分馏区,在该分馏区中回收C 3 3产物流,将富含C 4 O 3烯烃的物流循环至稀相反应 汽提区域与汽提区的密相分离。 烯烃可以进一步加工和聚合以形成各种聚合物材料。