Method for decomposing N.sub.2 O utilizing catalysts comprising calcined anionic clay minerals

An improved process for removing N.sub.2 O from an N.sub.2 O -containing gaseous mixture in which the process includes heat treating a catalyst precursor to form a catalyst and reacting the N.sub.2 O-containing gaseous mixture in the presence of said catalyst under conditions sufficient to convert the N.sub.2 O to gaseous nitrogen and gaseous oxygen, wherein the catalyst precursor comprises an anionic clay material represented by the formula M.sub.m N.sub.n (OH).sub.(2m+2n) A.sub.a.bH.sub.2 O wherein

• M is a divalent metal cation;
• N is a trivalent metal cation;
• A is a mono-, di- or trivalent anion which decomposes when heated to a temperature sufficient to form a volatile gas;
• m and n are such that m/n has values of 0.5 to about 6;
• a is a number with the provisos that when A is a monovalent anion,
• a=n, when A is a divalent anion, a=1/2 n and when A is a
• trivalent anion a=1/3 n;
• and
• b is an integer having values of 1 to 10,
• which anionic clay material is heated to the temperature sufficient to cause A, the mono-, di- or trivalent anion, to decompose to form the volatile gas, and
• wherein the improvement comprises
• providing the catalyst precursor with a minimum of about 1 percent by weight of an activator metal separate from M, selected from the group consisting of sodium, potassium, lithium, magnesium and mixtures thereof.