ATTRITION-RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS”

Historically Black College and University and Other Minority Institutions

J. Jothimurugesan

Others  :  http://www.netl.doe.gov/publications/proceedings/99/99hbcu/jothimu.pdf
PID  :  11027

来源: CEUR

【 摘 要 】

Operation of a Fischer-Tropsch (F-T) slurry bubble column reactors (SBCR) with an Fe catalyst is seriously limited due to attrition of the iron catalysts. The objective of this work is to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalyst having superior attrition resistance, activity, and selectivity. The effect of silica addition via coprecipitation and as a binder to a doubly promoted Fischer-Tropsch synthesis iron catalyst (100Fe/5 Cu/4.2K) was studied. The catalysts were prepared by coprecipitation, followed by binder silica addition and spray drying. A number of attrition methods including fluidized-bed, jet-cup, and ultrasound were developed for small quantities of catalysts and their results were compared with a standard ASTM method (D-5757-95). Binder silica addition up to a level of 10-12 wt% resulted in increased attrition resistance. Addition of precipitated silica, however, was found to be detrimental to attrition resistance and resulted in increased methane and reduced wax formation. An attrition resistant, active and selective catalyst was prepared that gave 95% CO conversion through 100 hours of testing in a fixed-bed at 250℃, 1.5 MPa and 1800 per hour space velocity with C+ selectivity of >78% and CH 5 4 selectivity of less than 5%.