(EP559926-A1)      A catalyst (A) for the conversion of methane to higher hydrocarbons comprises: (a) a support material which is Si, Zr and/or Mg oxides, (b) a Mn catalytic agent supported on (a) and (c) an alkali metal promoter impregnated into (A) where the surface atomic ratio of (c):(b) is at least 5.    (B) Prepn. of (A)involves forming a mixt. of Mn aq. soln. and an oxidative agent aq. soln. in an inorganic oxide support material, obtaining a ppte. of Mn oxide on the support material, drying the ppte., impregnating the ppte. with (c) and drying the calcining the obtd. catalyst.    Pref., the Mn oxide ppte. is obtd. by varying a pH value of the mixt. between acidic and basic values. The aq. Mn soln. is aq. soln. of MnCl3. The oxidative agent is alkali metal chlorate, hypochlorite, thiosulphate and/or bromate, pref. K chlorate. (c) is an alkali metal halide, pref. NaCl. process further comprises calcining the dried ppte. of (b) prior to impregnation, pref. at 900-1200 but partic. 1000 deg. C. (c) is pref. Si oxide. The impregnated solid is calcined at 300-1000 pref. 600-800 deg. C or at 100-140 deg. C. (a) is calcined prior to its mixt. with the solns. of (b) and (c).    USE/ADVANTAGE -   The catalyst provides stable and enhanced methane conversion levels over extended reaction times for conversion of methane to higher hydrocarbo    (JP5285384-A)      Catalyst, comprises a Mn catalyst carried on carriers of Si oxide, Zr oxide or Mg oxide and alkali metal accelerating agent impregnated in the catalyst.    USE -   For converting methane gas to higher hydrocarbons.    (JP95034863-B2)      A catalyst (A) for the conversion of methane to higher hydrocarbons comprises: (a) a support material which is Si, Zr and/or Mg oxides, (b) a Mn catalytic agent supported on (a) and (c) an alkali metal promoter impregnated into (A) where the surface atomic ratio of (c):(b) is at least 5.    (B) Prepn. of (A)involves forming a mixt. of Mn aq. soln. and an oxidative agent aq. soln. in an inorganic oxide support material, obtaining appts. of Mn oxide on the support material, drying the ppte., impregnating the ppte. with (c) and drying the calcining the obtd. catalyst.    Pref., the Mn oxide ppte. is obtd. by varying a pH value of the mixt. between acidic and basic values. The aq. Mn soln. is aq. soln. of MnCl3. The oxidative agent is alkali metal chlorate, hypochlorite, thiosulphate and/or bromate, pref. K chlorate. (c) is an alkali metal halide, pref. NaCl. process further comprises calcining the dried ppte. of (b) prior to impregnation, pref. at 900-1200 but partic. 1000 deg. C. (c) is pref. Si oxide. The impregnated solid is calcined at 300-1000 pref. 600-800 deg. C or at 100-140 deg. C. (a) is calcined prior to its mixt. with the solns. of (b) and (c).    USE/ADVANTAGE -   The catalyst provides stable and enhanced methane conversion levels over extended reaction times for conversion of methane to higher hydrocarbons.    (EP559926-B1)      A method for preparing a catalyst for conversion of methane to higher hydrocarbons, comprising the steps of: forming a mixture of a manganese aqueous solution and an oxidative agent aqueous solution in an inorganic oxide support material obtaining a precipitate of manganese oxide on the support material; drying the manganese oxide precipitate; impregnating the dried manganese oxide precipitate with an alkali metal promoter to obtain an impregnated solid; drying the impregnated solid; calcining the impregnated solid until a surface atomic ratio of promoter to manganese is at least 5.