[drdave]

Hello Sir,
In Isothermal shift reactor, Copper-Zinc catalysts is used to reduce CO content bare minimum. Topfed reactor has its hot-spot(ie Reactive zone) coming down faster after one annual shut down.
1)What is the effective life of copper zinc catalyst?
2)What are probable reasons of a bit faster downward movement after 1 or 2 annual shut down?
i)Is it mis-operation during blanketing ? In fact, It is not learnt through operation documents.
ii)Is it sulfur poisoning ? Of course, Reformer new catalyst desulfurisation is performed well in total isolation of Iso thermal reactor with inert blanketing.
3)How sulfur poisoning will affect to catalysts of reformer (Nickel based) & shift reactor(Copper&Zinc based) in its performance?
4)What are the chances / possibilities of sulfur leaching from reformer tube walls & contaminating shift reactors catalysts?
5)How can side reaction of methanol formation(~2000 ppm) in shift reactor be suppressed/minimized or totally stopped?

[mbeychok]

drdave:

I suggest that you also post your questions at:

www.nh3.org/ibx/comlink/

That forum has quite a bit of participations by ammonia synthesis plant operators and engineers.