This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having IWV topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation templates.

The present invention is related to a catalyst supported for the selective oxidation of sulphur compounds of the tail gas from the Claus process or streams with an equivalent composition to elemental sulphur or sulphur dioxide (SO.sub.2). It is also the object of the present invention, a process for the preparation of a catalyst of this type, as well as the process of selective oxidation of sulphur compounds to elemental sulphur using the catalyst of the invention, as well as the process of catalytic incineration of the tail gas from the Claus process using the catalyst of the present invention.

The present invention is related to a catalyst supported for the selective oxidation of sulphur compounds of the tail gas from the Claus process or streams with an equivalent composition to elemental sulphur or sulphur dioxide (SO.sub.2). It is also the object of the present invention, a process for the preparation of a catalyst of this type, as well as the process of selective oxidation of sulphur compounds to elemental sulphur using the catalyst of the invention, as well as the process of catalytic incineration of the tail gas from the Claus process using the catalyst of the present invention.

A method is disclosed for the preparation of a metal exchanged microporous materials, e.g. metal exchanged silicoaluminophosphates or metal exchanged zeolites, or mixtures of metal exchanged microporous materials, comprising the steps of providing a dry mixture of a) one or more microporous materials that exhibit ion exchange capacity and b) one or more metal compounds; heating the mixture in a gaseous atmosphere containing ammonia and one or more oxides of nitrogen to a temperature and for a time sufficient to initiate and perform a solid state ion exchange of ions of the metal compound and ions of the microporous material; and obtaining the metal-exchanged microporous material.

A catalyst is illustrated, which has 70-90 parts by weight of mica, 1-10 parts by weight of zeolite, 5-15 parts by weight of titanium dioxide, 1-10 parts by weight of aluminum oxide, 1-5 parts by weight of sodium oxide and 1-5 parts by weight of potassium oxide. The present disclosure also illustrates a pyrolysis device using the catalyst, and further illustrates a pyrolysis method using the catalyst and/or the pyrolysis device for thermally cracking an organic polymer.

A catalyst is illustrated, which has 70-90 parts by weight of mica, 1-10 parts by weight of zeolite, 5-15 parts by weight of titanium dioxide, 1-10 parts by weight of aluminum oxide, 1-5 parts by weight of sodium oxide and 1-5 parts by weight of potassium oxide. The present disclosure also illustrates a pyrolysis device using the catalyst, and further illustrates a pyrolysis method using the catalyst and/or the pyrolysis device for thermally cracking an organic polymer.

A honeycomb structure comprising: a honeycomb structure body that includes a plurality of porous partition walls and intersection parts, and a catalyst layer, wherein the porosity of the partition wall is 20 to 70%, the average pore diameter of the pores in the partition wall is 1 to 60 μm, a plurality of the partition walls includes a notched partition wall having a recessed part in which at least one end is notched, the ratio of the notched partition wall in the partition walls is 1 to 100%, the recessed part of the notched partition wall has a depth of 10 to 200% of the standard length, and the recessed part of the notched partition wall is a part having a width of 33 to 100% of the standard width.

A honeycomb structure comprising: a honeycomb structure body that includes a plurality of porous partition walls and intersection parts, and a catalyst layer, wherein the porosity of the partition wall is 20 to 70%, the average pore diameter of the pores in the partition wall is 1 to 60 μm, a plurality of the partition walls includes a notched partition wall having a recessed part in which at least one end is notched, the ratio of the notched partition wall in the partition walls is 1 to 100%, the recessed part of the notched partition wall has a depth of 10 to 200% of the standard length, and the recessed part of the notched partition wall is a part having a width of 33 to 100% of the standard width.

The invention relates to a process and apparatus for preparing nitric acid by catalytic oxidation of NH.sub.3 by means of oxygen and subsequent reaction of the NO.sub.x formed with an absorption medium in an absorption tower, which comprises a catalyst bed for N.sub.2O decomposition arranged in the process gas downstream of the catalytic NH.sub.3 oxidation and upstream of the absorption tower in the flow direction and a catalyst bed for NO.sub.x reduction and effecting a further decrease in the amount of N.sub.2O arranged in the tailgas downstream of the absorption tower in the flow direction, wherein the amount of N.sub.2O removed in the catalyst bed for N.sub.2O removal arranged in the process gas is not more than that which results in an N.sub.2O content of >100 ppmv and a molar N.sub.2O/NO.sub.x ratio of >0.25 before entry of the tailgas into the catalyst bed for NO.sub.x reduction and the catalyst bed for NO.sub.x reduction and effecting a further decrease in the amount of N.sub.2O arranged in the tailgas contains at least one iron-loaded zeolite catalyst and NH.sub.3 is added to the tailgas before entry into the catalyst bed in such an amount that an NO.sub.x concentration of <40 ppmv results at the outlet from the catalyst bed and the operating parameters are selected in such a way that an N.sub.2O concentration of <200 ppmv results.

The invention relates to a process and apparatus for preparing nitric acid by catalytic oxidation of NH.sub.3 by means of oxygen and subsequent reaction of the NO.sub.x formed with an absorption medium in an absorption tower, which comprises a catalyst bed for N.sub.2O decomposition arranged in the process gas downstream of the catalytic NH.sub.3 oxidation and upstream of the absorption tower in the flow direction and a catalyst bed for NO.sub.x reduction and effecting a further decrease in the amount of N.sub.2O arranged in the tailgas downstream of the absorption tower in the flow direction, wherein the amount of N.sub.2O removed in the catalyst bed for N.sub.2O removal arranged in the process gas is not more than that which results in an N.sub.2O content of >100 ppmv and a molar N.sub.2O/NO.sub.x ratio of >0.25 before entry of the tailgas into the catalyst bed for NO.sub.x reduction and the catalyst bed for NO.sub.x reduction and effecting a further decrease in the amount of N.sub.2O arranged in the tailgas contains at least one iron-loaded zeolite catalyst and NH.sub.3 is added to the tailgas before entry into the catalyst bed in such an amount that an NO.sub.x concentration of <40 ppmv results at the outlet from the catalyst bed and the operating parameters are selected in such a way that an N.sub.2O concentration of <200 ppmv results.