Preparation and use of isomerization catalysts

An alkane conversion process which comprises the step of contacting, at a temperature of up to about 100.degree. C., at least one feed alkane containing about 4-10 carbon atoms per molecule with an isomerization catalyst composition at effective isomerization conditions and producing at least one product alkane isomer having the same number of carbon atoms per molecule as said at least one feed alkane but having a different structural formula;

• wherein said catalyst composition has been prepared by a preparation method consisting essentially of the steps of
• (1) impregnating alumina having a surface area of at least about 40 m.sup.2 /g with a solution of at least one metal salt selected from the group consisting of copper(II) sulfate and nickel(II) sulfate;
• (2) calcining the material obtained in step (1) for a period of at least one hour at a temperature of about 400.degree.-750.degree. C.;
• (3) heating for a period of at least one hour, at a temperature in the range of about 40.degree. C. to about 90.degree. C. and in substantial absence of water, a mixture consisting essentially of the calcined material obtained in step (2), aluminum chloride and at least one chlorinated hydrocarbon selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1-dichloropropane, 2,2-dichloropropane, 1-chlorobutane and 2-chloro-2-methylbutane;
• wherein the weight ratio of AlCl.sub.3 to said calcined material obtained in step (2) is at least about 0.35:1;
• and
• (4) separating the solid material contained in the reaction mixture formed in step (3) from said at least one chlorinated hydrocarbon under a dry gas atmosphere.

An alkane conversion process which comprises the step of contacting, at a temperature of up to about 100.degree. C., at least one feed alkane containing about 4-10 carbon atoms per molecule with an isomerization catalyst composition at effective isomerization conditions, and producing at least one product alkane isomer having the same number of carbon atoms per molecule as said at least one feed alkane but having a different structural formula;

• wherein said isomerization catalyst composition has been prepared by a preparation method consisting essentially of the steps of:
• (1) impregnating alumina having a surface area of at least about 40 m.sup.2 /g with a solution of at least one metal salt selected from the group consisting of copper(II) sulfate, iron(II) sulfate, cobalt(II) sulfate, nickel(II) sulfate, manganese(II) sulfate, zinc sulfate and magnesium sulfate;
• (2) calcining the material obtained in step (1) for a period of at least one hour at a temperature of about 400.degree.-750.degree. C.;
• (2a) contacting the calcined material obtained in Step (2) with dry gaseous hydrogen chloride at a temperature of about 600.degree.-750.degree. C. for at least about 10 minutes;
• (3) heating for a period of at least one hour, at a temperature in the range of about 40.degree. C. to about 90.degree. C. and in substantial absence of water, a mixture consisting essentially of the calcined material obtained in step (2), aluminum chloride and at least one chlorinated hydrocarbon selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1-dichloropropane, 2,2-dichloropropane, 1-chlorobutane and 2-chloro-2-methylbutane;
• wherein the weight ratio of AlCl.sub.3 to said calcined material obtained in step (2) is at least about 0.35:1;
• and
• (4) separating the solid material contained in the reaction mixture formed in step (3) from said at least one chlorinated hydrocarbon under a dry gas atmosphere.

A cycloalkane conversion process which comprises contacting, at a temperature of up to about 100.degree. C., at least one feed cycloalkane containing 5-10 carbon atoms per molecule with an isomerization catalyst composition at effective isomerization conditions, and producing at least one product cycloalkane isomer having the same number of carbon atoms per molecule as said at least one feed cycloalkane but having a different structural formula;

• wherein said isomerization catalyst composition has been prepared by a preparation method consisting essentially of the steps of:
• (1) impregnating alumina having a surface area of at least about 40 m.sup.2 /g with a solution of at least one metal salt selected from the group consisting of copper(II) sulfate, iron(II) sulfate, cobalt(II) sulfate, nickel(II) sulfate, manganese(II) sulfate, zinc sulfate and magnesium sulfate;
• (2) calcining the material obtained in step (1) for a period of at least 0.5 hour at a temperature of about 400.degree.-750.degree. C.;
• (2a) of contacting the calcined material obtained in step (2) with dry gaseous hydrogen chloride at a temperature of about 600.degree.-750.degree. C. for at least about 10 minutes;
• (3) heating for a period of at least one hour, at a temperature in the range of about 40.degree. C. to about 90.degree. C. and in substantial absence of water, a mixture consisting essentially of the calcined material obtained in step (2a), aluminum chloride and at least one chlorinated hydrocarbon selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, 1,1-dichloropropane, 2,2-dichloropropane, 1-chlorobutane and 2-chloro-2-methylbutane;
• wherein the weight ratio of AlCl.sub.3 to said calcined material obtained in step (2) is at least about 0.35:1;
• and
• (4) separating the solid material contained in the reaction mixture formed in step (3) from said at least one chlorinated hydrocarbon under a dry gas atmosphere.