Abstract: There is disclosed a process for denitrifying tobacco materials and removing barium from tobacco materials, comprising mixing an aqueous-immiscible organic solvent containing a crown ether with an aqueous solution containing soluble components from tobacco materials, agitating this mixture, and separating the organic phase containing a crown ether-cation-nitrate (or nitrite) complex from the aqueous phase containing the denitrified tobacco materials, wherein the cation consists essentially of barium and potassium. There is further disclosed a process for eliminating tobacco-specific nitrosamines (TSNAs) from cured, denitrified tobacco material, comprising contacting the denitrified tobacco material with a trapping sink, wherein the trapping sink comprises a select transition metal complex which is readily nitrosated to form a nitrosyl complex with little kinetic or thermodynamic hindrance.

Abstract: There is disclosed a process for producing premium grades of metal oxide comprising (1) providing wet or dried hydrous metal oxide containing high levels (e.g., 2%-10% chloride) of halogen contamination, (2) treating the contaminated metal oxide with a base in gas phase, which base is volatile at .ltoreq.900.degree. C., at a final temperature of between 750.degree. C. to no greater than 900.degree. C. wherein the temperature is brought to the final temperature in increments of about 25.degree. C., until gas exiting shows no additional evolution of a halogen conjugated acid, and (3) exposing the treated metal oxide to air or oxygen at a temperature of 500.degree. to 600.degree. C. to convert any metal nitrides or oxynitrides present to metal oxide, wherein the metal oxide is selected from the group consisting of Ta.sub.2 O.sub.5, niobium oxide, hafnium oxide, zirconium oxide and titanium oxide. The inventive process yields a premium grade, high active surface area .beta.-Ta.sub.2 O.sub.