PROMOTERS AND POISONS, TYPES OF CATALYSTS

Catalyst and Catalysis || Homogenous and Heterogenous Catalysis || Positive, Negative, Auto and Induced Catalysis || Promoters and Poisons

Poison for platinum, a catalyst in Contact process is

Which acts as poison for Pd-charcoal in Lindlar's catalyst ?

Poison for platinum, a catalyst in contact process of H_2 SO_4 is ___.