Method and composition for sequestration of arsenic
AssigneeDundee, Technologies Durables Inc.
InventorsJean-Marc Lalancette, Bertrand Dubreuil, David Lemieux
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Abstract
A method for sequestrating arsenic oxides, comprising forming an insoluble and stable glass incorporating a fully oxidized form of arsenic generated by oxidation of an initial lower oxide of arsenic and stabilization by calcium salt formation. The glass composition for sequestration of arsenic comprises from 50 to 75% silica; from 0.5 to 3% Al2O3; from 1 to 15% MnO; from 5 to 15% CaO; from 1 to 20% As2O5 and from 8 to 14% Na2O, less than four percent of iron oxides, magnesium oxide and other oxides.
Claims13
A method for sequestrating arsenic oxides, comprising forming an insoluble and stable glass by mixing an initial lower oxide of arsenic with one of:
- i) glass-forming elements and ii) recycled glass;
- adding an oxidizing agent, for oxidizing the initial lower oxide of arsenic into a fully oxidized form of arsenic, and at least one of:
- i) calcium oxide and ii) calcium hydroxide for stabilization of arsenic by calcium salt formation;
- and a heating cycle.
A method for sequestrating arsenic oxides, comprising forming an insoluble and stable glass having a composition by weight of from 50 to 75% silica;
- from 0.5 to 3% alumina;
- from 1 to 15% manganese oxide;
- from 5 to 15% calcium oxide;
- from 1 to 20% arsenic calculated as arsenic oxide and from 8 to 14% of sodium oxide, and less than four percent of iron oxides, magnesium oxide and other oxides.
A glass composition, comprising from 50 to 75% silica;
- from 0.5 to 3% Al2O3;
- from 1 to 15% MnO;
- from 5 to 15% CaO;
- from 1 to 20% As2O5 and from 8 to 14% Na2O, less than four percent of iron oxides, magnesium oxide and other oxides.
Dependencies are inferred from the claim text.