Methods of converting a variety of fluorinated materials into anhydrous hydrogen fluoride are described. The methods include thermally decomposing the fluorinated materials into a gaseous effluent comprising hydrogen fluoride and carbon dioxide. This gaseous effluent is then treated with carbon at a temperature of at least 830 C., converting the carbon dioxide to carbon monoxide (CO) and producing a gaseous product comprising the hydrogen fluoride, which can be condensed to generate anhydrous hydrogen fluoride. These methods can also be used to convert water contained in the gaseous effluent into hydrogen.

The present disclosure discloses a method for graded utilization of fluorine and silicon resources in a phosphate ore. While the phosphate ore reacts with sulfuric acid, a fluorine-containing and silicon-containing tail gas is produced. SiO.sub.2 and H.sub.2SiF.sub.6 solution with a high concentration are obtained by concentrating and filtering a solution containing HF and H.sub.2SiF.sub.6 formed after tail gas is absorbed by water. Crude SiF.sub.4 and a solution containing HF and H.sub.2SO.sub.4 are obtained by extracting, adsorbing, and dehydrating the H.sub.2SiF.sub.6 solution. SiF.sub.4 with a 5N purity is obtained after the crude SiF.sub.4 is adsorbed and distilled, at the same time, an impurity-enriched SiF.sub.4 is returned to operations of concentration and filtration to react with the solution containing HF and H.sub.2SiF.sub.6 to generate the H.sub.2SiF.sub.6 and SiO.sub.2. High-purity HF and waste sulfuric acid are obtained after the H.sub.2SO.sub.4 solution containing HF is separated by steam stripping and distillation.

The present disclosure discloses a method for graded utilization of fluorine and silicon resources in a phosphate ore. While the phosphate ore reacts with sulfuric acid, a fluorine-containing and silicon-containing tail gas is produced. SiO.sub.2 and H.sub.2SiF.sub.6 solution with a high concentration are obtained by concentrating and filtering a solution containing HF and H.sub.2SiF.sub.6 formed after tail gas is absorbed by water. Crude SiF.sub.4 and a solution containing HF and H.sub.2SO.sub.4 are obtained by extracting, adsorbing, and dehydrating the H.sub.2SiF.sub.6 solution. SiF.sub.4 with a 5N purity is obtained after the crude SiF.sub.4 is adsorbed and distilled, at the same time, an impurity-enriched SiF.sub.4 is returned to operations of concentration and filtration to react with the solution containing HF and H.sub.2SiF.sub.6 to generate the H.sub.2SiF.sub.6 and SiO.sub.2. High-purity HF and waste sulfuric acid are obtained after the H.sub.2SO.sub.4 solution containing HF is separated by steam stripping and distillation.

The present disclosure provides separation processes for removing heavy organics that are formed in various production processes of HCFO-1233zd(E). Such separation processes allow for the recovery and/or separation of the heavy organics from reactants that are used to form HCFO-1233zd(E), including HF. Such separation or recovery processes may utilize various separation techniques (e.g., decanting, liquid-liquid separation, distillation, and flash distillation) and may also utilize the unique properties of azeotropic or azeotrope-like compositions. Recovery of the heavy organic that is substantially free from HF may allow for their use in subsequent manufacture processes or disposal.

A method for measuring the concentration of fluorine gas (F.sub.2) contained in a halogen fluoride-containing gas using an analysis apparatus having a halogen fluoride-containing gas supply source, a fluorine-containing gas supply source, a tube, a capillary, and a mass spectrometer, the method including, before measuring the concentration of fluorine gas, performing passivation treatment on the tube and the capillary using a passivation gas containing a fluorine-containing gas supplied from the fluorine-containing gas supply source.

An inhibited hydrofluoric acid aqueous composition, said composition comprising: hydrofluoric acid in solution; and an alkanolamine; wherein said alkanolamine and hydrofluoric acid are present in a molar ratio of at least 1:1.

The present invention provides a process for preparing 2,3,3,3-tetrafluoropropene from 1,1,1,2,3-pentachloropropane and/or 1,1,2,2,3-pentachloropropane, comprising the following steps: (a) catalytic reaction of 1,1,1,2,3-pentachloropropane and/or 1,1,2,2,3-pentachloropropane with HF into a reaction mixture comprising HCl, 2-chloro-3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, unreacted HF, and optionally 1,1,1,2,2-pentafluoropropane; (b) separating the reaction mixture into a first stream comprising HCl and 2,3,3,3-tetrafluoropropene and a second stream comprising HF, 2-chloro-3,3,3-trifluoropropene and optionally 1,1,1,2,2-pentafluoropropane; (c) catalytic reaction of the second stream into a reaction mixture comprising 2,3,3,3-tetrafluoropropene, HCl, unreacted 2-chloro-3,3,3-trifluoropropene, unreacted HF and optionally 1,1,1,2,2-pentafluoropropane and (d) feeding the reaction mixture of step (c) directly without separation to step (a).

A method of preparing aqueous hydrogen fluoride is provided. The method includes providing a composition including a cross-linked polymer with absorbed hydrogen fluoride. The cross-linked copolymer includes acrylamide units and acrylic acid salt units. The method further includes contacting the composition with water to release at least a portion of the hydrogen fluoride from the composition to the water to form the aqueous hydrogen fluoride.

The present invention discloses a method and apparatus for purifying ultra-high purity hydrogen fluoride, which purify it through a continuous distillation process by putting crude hydrogen fluoride instead of hydrogen fluoride into a multi-stage distillation column as it is, and remove impurities in hydrogen fluoride through a contact with fluorine gas having the concentration of the F.sub.2 gas automatically controlled depending on the content of arsenic fluoride that is an impurity.

The present invention discloses a method and apparatus for purifying ultra-high purity hydrogen fluoride, which purify it through a continuous distillation process by putting crude hydrogen fluoride instead of hydrogen fluoride into a multi-stage distillation column as it is, and remove impurities in hydrogen fluoride through a contact with fluorine gas having the concentration of the F.sub.2 gas automatically controlled depending on the content of arsenic fluoride that is an impurity.