Porous refractory body impregnated with magnesium

Claim 2

Composition according to claim 1 in which the alkaline earth metal oxide is calcium oxide.

Claim 3

Composition according to claim 1 in which the porous refractory body composition is impregnated with an alloy of magnesium.

Claim 4

A porous compressed refractory body composition comprising a porous structure of an alkaline earth metal oxide and a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, said structure containing magnesium absorbed in the interstices of said porous structure, the alkaline earth metal oxide having an average particle size below 4 mesh, the amount of said alkaline earth metal oxide being present in amount from about 30 percent to about 50 percent, said binder being present in amount from about 1 percent to about 15 percent and said composition being impregnated with at least about 35 percent magnesium absorbed in said structure, all of the percentages expressed on a weight basis.

Claim 5

A process for producing a porous, compressed refractory body comprising a porous structure of an alkaline earth metal oxide and a ceramic binder, said binder selected from the group consisting of clay, water, glass, cement and mixtures thereof, said structure containing magnesium absorbed in the interstices of said porous structure, said process which comprises admixing a particulate alkaline earth metal carbonate and a ceramic binder, the amount of said alkaline earth metal carbonate being present in amount from about 75 percent to about 99 percent, said ceramic binder being present in amount from about 1 percent to about 25 percent, all of the percentages expressed on a weight basis, forming pellets of said mixture, drying and firing said pellets at a temperature sufficient to convert the metal carbonate to metal oxide and to volatilize the carbon dioxide formed, thus forming a porous, compressed structure of a ceramic body, and impregnating the pores of said body with magnesium.

Claim 6

A process for producing a porous, compressed refractory body comprising a porous structure of an alkaline earth metal oxide and a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, said structure containing magnesium absorbed in the interstices of said porous structure, said process which comprises admixing a particulate alkaline earth metal carbonate and a ceramic binder, said alkaline earth metal carbonate being present in amount from about 75 percent to about 99 percent, said ceramic binder being present in amount from about 1 percent to about 25 percent, all of the percentages expressed on a weight basis, adding to said mixture sufficient water to form a moldable mixture, forming pellets from said mixture, drying and firing said pellets at a temperature from about 875* C to about 1,450* C to convert the metal carbonate to metal oxide and to volatilize the carbon dioxide formed, thus forming a porous, compressed and open structure of a ceramic body, immersing said body with magnesium and removing said impregnated body from said molten metal.

Claim 7

Process according to claim 7 in which the moldable mixture is compressed at a pressure from about 1,500 psi to about 30,000 psi to form pellets.

Claim 8

Process according to claim 7 in which the moldable mixture is extruded to form pellets.

Claim 9

Process according to claim 7 in which the alkaline earth metal carbonate is calcium carbonate.

Claim 10

Process according to claim 7 in which the alkaline earth metal carbonate is of a size of -4 mesh.

Claim 11

A process for producing a porous, refractory body comprising a porous structure of an alkaline earth metal oxide and a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, said structure containing magnesium absorbed in the interstices of said porous structure, said process which comprises admixing a particulate alkaline earth metal carbonate, a ceramic binder and a cellulosic material, the amount of said alkaline earth metal carbonate being present in amount from about 55 percent to about 70 percent, said cellulosic material being present in amount from 10 percent to 30 percent, all of the percentages expressed on a weight basis, adding to said mixture from about 2 percent to about 6 percent water to form a moldable mixture, forming pellets from said mixture, drying and firing said pellets at a temperature from about 875* C to about 1,450* C to volatilize the carbon dioxide formed and to burn off the cellulosic material, thus forming pellets of a porous ceramic body having an open structure comprising said alkaline earth metal oxide and said binder, immersing said body in molten magnesium metal to fill the pores of said structure with magnesium and removing said impregnated body from said molten metal.

Claim 12

Process according to claim 12 in which the size of the cellulosic material employed is -20 mesh.

Claim 13

Process according to claim 12 in which the cellulosic material is selected from the group consisting of sawdust, corn cob grits, corn stalks and oat hulls, and mixtures thereof.

Claim 14

A process for treating molten iron which comprises immersing a porous structure comprising a refractory body composition impregnated with magnesium into said molten iron to reduce the sulfur content thereof, the porous refractory body composition comprising an alkaline earth metal oxide and a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, said refractory binder having from about 2 to about 50 parts by weight of alkaline earth metal oxide for each part of binder, the alkaline earth metal oxide present in said composition having an average particle size below 4 mesh, and said composition being impregnated into the pores of said structure with at least about 35 percent by weight of magnesium.

Claim 15

A process for treating molten iron which comprises immersing a porous structure comprising a refractory body impregnated with magnesium into said molten iron to reduce the sulfur content thereof, said porous refractory body comprising from about 30 percent to about 50 percent alkaline earth metal oxide, from about 1 percent to about 15 percent of a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, and sAid body impregnated into the pores of said structure with from about 35 percent to about 70 percent magnesium, all of the percentages expressed on a weight basis.

Claim 16

Process according to claim 16 in which the magnesium employed is a magnesium alloy.

Claim 17

A process for desulfurizing molten iron which comprises immersing a porous structure comprising a refractory body impregnated with magnesium into said molten iron for a period of about 1 to about 10 minutes and removing said body from said molten iron after said period, said refractory body comprising from about 30 percent to about 50 percent alkaline earth metal oxide, from about 1 percent to about 15 percent of a ceramic binder, said binder selected from the group consisting of clay, water glass, cement and mixtures thereof, and said body impregnated into the pores of said structure with from about 35 percent to about 70 percent magnesium, all of the percentages expressed on a weight basis.