Abstract: The effect of ammonia concentration on the temperature sensibility of isomerization-hydrocracking catalyst for F-T synthetic wax was studied in pilot plant. The results indicate that the catalyst exhibits a strong temperature sensibility in the case of NH3-free. The activity of catalyst is remarkably restrained by NH3 addition, meanwhile the temperature sensibility of catalyst is improved significantly. Neither changes in the relationship of conversion and selectivity nor the properties of liquid product occur after adding ammonia, except the reduction of influence of temperature fluctuation on stable operation of the unit.

Key words: F-T synthetic wax, isomerization-hydrocracking, NH3, temperature sensibility