Extraction of anhydrous hydrogen fluoride from its aqueous solution is provided. A method provides hydrogen fluoride from aqueous solutions, including the reduction of water component of the aqueous solution at an elevated temperature into carbon oxide, carbon dioxide and hydrogen. The condensation and distillation of the obtained hydrogen fluoride and water vapor are characterized by the fact that the mixture of hydrogen fluoride and water is reduced at a temperature of 800 K and above, the molar ratio of carbon to water in the reducing agent is from 0.5 to 4, and using a reducing agent of the general formula C.sub.nH.sub.mO.sub.k, where k≥0, m>0, and n>0, and the reducing agent may be saturated, unsaturated, aromatic hydrocarbons, oxygen-containing organic compounds, their isomers and their mixtures. The method makes it possible to extract hydrogen fluoride from its mixtures with water in any ratio and from azeotropic mixtures.

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.

Embodiments of the invention relate to a process for removing fluoride from a solution or suspension containing zinc, in particular a solution of zinc sulfate, a defluoridated solution of zinc sulfate obtainable by such a process, its use as well as processes for producing zinc and hydrogen fluoride or hydrofluoric acid. The process for removing fluoride comprises (i) providing a solution or suspension A containing zinc, wherein the solution or suspension A containing zinc further contains fluoride ions; (ii) adding a solution B containing a dissolved salt of a rare earth element to the solution or suspension A containing zinc, wherein a solid comprising a rare earth element fluoride and a solution C containing zinc are formed; and (iii) separating the solid from the solution C containing zinc, wherein the solution C containing zinc has a lower concentration of fluoride ions than the solution or suspension A containing zinc.

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 provides a novel azeotropic or azeotrope-like composition comprising hydrogen fluoride and 1,1,2-trifluoroethane (HFC-143), 1-chloro-2, 2-difluoroethane (HCFC-142), or 1,2-dichloro-1-fluoroethane (HCFC-141); and a separation method using the composition.

An azeotropic or azeotrope-like composition comprising hydrogen fluoride and HFC-143. An azeotropic or azeotrope-like composition comprising hydrogen fluoride and HCFC-142. An azeotropic or azeotrope-like composition comprising hydrogen fluoride and HCFC-141. A separation method of a composition comprising hydrogen fluoride and at least one member selected from the group consisting of HFC-143, HCFC-142, and HCFC-141.

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.

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.

This disclosure provides a novel azeotrope-like composition and a separation method using the composition. The disclosure provides an azeotrope-like composition comprising 1,2-difluoroethylene (HFO-1132) and hydrogen fluoride; an azeotrope-like composition comprising 1,1,2-trifluoroethylene (HFO-1123) and hydrogen fluoride; and a separation method of a composition comprising hydrogen fluoride and at least one member selected from the group consisting of trans-1,2-difluoroethylene (HFO-1132(E)), cis-1,2-difluoroethylene (HFO-1132(Z)), and 1,1,2-trifluoroethylene (HFO-1123).

This invention provides a method for stably producing 2,3,3,3-tetrafluoropropene for a long period of time wherein unreacted materials are reused after distillation without liquid-liquid separation to suppress catalyst deactivation. The method for producing 2,3,3,3-tetrafluoropropene comprises the step of reacting 1233xf or like chloropropene with hydrogen fluoride in the presence of a catalyst, the step of subjecting the reaction mixture obtained in the above step to distillation to separate the mixture into a first stream comprising 2,3,3,3-tetrafluoropropene as a main component and a second stream comprising unreacted hydrogen fluoride and organic matter containing unreacted chloropropene as main components, and the step of recycling the second stream to the above reaction, the distillation being performed under conditions in which the unreacted hydrogen fluoride and the organic matter containing the unreacted chloropropene do not undergo liquid-liquid separation at a portion of a distillation column from which the second stream is withdrawn.