Page 217 - Principles of Catalyst Development

206 CHAPTER 8
TABLE 8.6. Toxicity of Nonmetallic Ions to Metals"

Group Element Toxic ion Nontoxic ion
-----"----_.
["t"l

Vb N H:N:H
H [ r

.. 0 o
P H: P: H o-i-
..
[ r
H

As H As:H o-i - o
0 s
H [ r
0 o
[ r
Vlb S H:S: H o--i-

..
R"
R:S: R' R-i- R'

u Reference 273.

hydrogen treatment. Surface sulfur is held much more strongly than in the
bulk, so that sulfides may reduce yet retain sulfur-poisoned surfaces. (274)
At higher temperatures, however, removal of sulfur by hydrogen and steam
is much faster, so that sulfur resistance in steam reforming is much higher. (49)

TABLE 8.7. Toxicity of Metal Ions to Platinum

Toxic ions Nontoxic (ons
Zn2+ Li+ Be2+
2
Cd ' In J • Na' Mg2+ AI3+
Hg2+ Sn 2 + K+ Ca2+
Hg+ Rb+ Sr H Zr4+
TI' Pb" Cs + Ba'+ La}'
Ce H
Cu+Cu2+ Ag+ Au+ Th 4 +
Mnl+Fe 2 +Col+Ni 2 + Cr 2 + Cr3+