Patent Number: 056132417
Section: claims

1. A process for treating a halogen-containing waste material comprising the steps of: providing a bath of molten glass containing a sacrificial metal oxide capable of reacting with a halogen in the waste material, wherein the sacrificial metal oxide is present in at least a stoichiometric amount with respect to the halogen in the waste material;  introducing the waste material into the bath of molten glass to cause a reaction between the halogen in the waste material and the sacrificial metal oxide to yield a metal halide which is a gas at the temperature of the molten glass;  separating the gaseous metal halide from the molten glass;  contacting the gaseous metal halide with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal-containing precipitate and a soluble alkali metal halide;  separating the precipitate from the aqueous scrubber solution; and  removing the molten glass containing the treated waste material as a waste glass.  providing a bath of molten glass containing at least one sacrificial metal oxide, wherein at least one sacrificial metal oxide is capable of reacting with a halogen in the waste material, or of oxidizing elemental metal or carbon-containing compounds within the waste material, and the sacrificial metal oxide is present in at least a stoichiometric amount for the reaction or the oxidation;  introducing the waste material into the bath of molten glass to cause a reaction between the waste material and the sacrificial metal oxide, wherein at least one sacrificial metal oxide reacts with a halogen in the waste material to yield a metal halide which is a gas at the temperature of the molten glass and at least one sacrificial metal oxide oxidizes elemental metal to form an oxide of the elemental metal which is soluble in the molten glass or oxidizes the carbon-containing compound thereby reducing the sacrificial metal oxide to its elemental metal;  separating the gaseous metal halide from the molten glass;  contacting the gaseous metal halide with an aqueous scrubber solution of an alkali metal hydroxide to yield a metal-containing precipitate and a soluble alkali metal halide;  separating the precipitate from the aqueous scrubber solution;  removing the molten glass containing the treated waste material as a waste glass; and  recovering the elemental metal derived from the sacrificial metal oxide from the bath.  oxidizing the recovered elemental metal derived from the sacrificial metal oxide; and  reintroducing the oxidized recovered elemental metal into the molten glass.  adding carbon to the molten waste glass containing the treated waste material to reduce any remaining sacrificial metal oxide to its elemental metal;  recovering the elemental metal derived from the sacrificial metal oxide;  oxidizing the recovered elemental metal derived from the sacrificial metal oxide; and  recycling the oxidized recovered elemental metal into the bath of molten glass containing the sacrificial metal oxide. 2. A process of claim 1, wherein the molten glass is a molten lead borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is PbO. 3. A process of claim 2, wherein the halogen-containing waste material is radioactive waste. 4. A process of claim 2, further comprising the step of reintroducing the separated precipitate to the molten glass. 5. A process of claim 1, wherein the molten glass is a molten bismuth borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is Bi.sub.2 O.sub.3. 6. A process of claim 5, wherein the halogen-containing waste material is radioactive waste. 7. A process of claim 5, further comprising the step of reintroducing the separated precipitate to the molten glass. 8. A process for the conversion of waste material containing halogen-containing compounds and elemental metal or carbon-containing compounds comprising the steps of: 9. A process of claim 8, wherein the molten glass is a molten lead borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is PbO. 10. A process of claim 8, wherein the halogen-containing waste material is radioactive waste. 11. A process of claim 8, wherein the molten glass is a molten bismuth borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is Bi.sub.2 O.sub.3. 12. A process of claim 11, wherein the halogen-containing waste material is radioactive waste. 13. A process of claim 8, further comprising the steps of: 14. A process of claim 13, further comprising the step of reintroducing the separated precipitate to the molten glass. 15. A process of claim 8, further comprising the steps of: 16. A process of claim 15, further comprising the step of reintroducing the separated precipitate to the molten glass. 17. A process of claim 15, wherein the molten glass is a molten lead borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is PbO. 18. A process of claim 17, wherein the halogen-containing waste material is radioactive waste. 19. A process of claim 15, wherein the molten glass is a molten bismuth borate glass having a temperature between 800.degree.-1400.degree. C. and the sacrificial metal oxide is Bi.sub.2 O.sub.3. 20. A process of claim 19, wherein the halogen-containing waste material is radioactive waste.