Thorium(IV) nitrate tetrahydrate.

white crystal(s); slightly deliquescent; used in thoriated tungsten filaments and as a reagent for fluoride determination [HAW93] [MER06]

Monazite alkali-dissolved cake nitric acid process monazite concentrate is decomposed and reacted with 50% sodium hydroxide at 140℃ for 5h, the alkali:ore is 1.3 (mass ratio), then the reactant is diluted with hot water, and kept at 70℃ After separation, monazite alkali-soluble cake is obtained. The alkali-dissolved cake is completely dissolved in nitric acid, and the uranium and thorium are extracted with 30% tributyl phosphate (TBP). The aqueous phase is a rare earth nitrate solution, which can be used to extract rare earths. The uranium and thorium enter the organic phase, and the uranium and thorium are obtained by reverse extraction with pure water. After concentration, uranium and thorium are extracted with 6% tributyl phosphate, and thorium is extracted with 40% TBP-kerosene solution, and then subjected to reverse extraction, concentration and crystallization. , To obtain thorium nitrate. RePO4+3NaOH→Re(OH)↓+Na3PO4Th3(PO4)4+12NaOH→3Th(OH)4+4Na3PO4Th(OH)4+4HNO3→Th(NO3)4+4H2O

It is used for steam lamp gauze luminous body and is the raw material for preparing thorium compound. Used as analytical reagents, such as the determination of fluorine, is an oxidant.