This disclosure relates to methods of converting an HF alkylation unit which utilizes HF as a reaction catalyst to a sulfuric acid alkylation unit which utilizes sulfuric acid as a reaction catalyst. This disclosure also relates to a segmented sulfuric acid settler for separating a sulfuric acid phase from a hydrocarbon phase. This disclosure also relates to methods of converting a vertical HF acid settler to a segmented sulfuric acid settler. This disclosure also relates to converted sulfuric acid alkylation units and alkylation processes performed in the converted sulfuric acid alkylation units.

The present invention provides a novel method for producing hydrogen fluoride which can suppress the occurrence of the pasty state over the whole process of producing hydrogen fluoride, reduce the problem of corrosion caused by sulfuric acid, and improve energy efficiency of the process. A method for producing hydrogen fluoride by reacting calcium fluoride and sulfuric acid comprises: (a) mixing and reacting calcium fluoride and sulfuric acid such that a mixture comprising calcium fluoride particles and sulfuric acid substantially maintains a form of particulate to obtain hydrogen fluoride while supplying sulfuric acid to the calcium fluoride particles at a flow rate of 0.002 to 1 mol/min relative to 1 mol of calcium fluoride to such an amount that a molar ratio of sulfuric acid/calcium fluoride is 0.9 to 1.1.

This disclosure relates to SA alkylation reactor systems. The reactor system involves a closed reactor vessel comprising a shell, a vapor outlet, and an emulsion outlet. The reactor system also involves a distributor located at the lower portion of the reactor vessel, a mixer fluidly connected with the distributor, and an emulsion pump fluidly connected with the mixer and the emulsion outlet, wherein the emulsion pump is located outside the reactor vessel. This disclosure also relates to a split SA alkylation reactor system wherein a single horizontal reactor vessel is divided to accommodate two reactor systems. This disclosure also relates to alkylation processes using the reactor systems. This disclosure also relates to methods of converting an HF alkylation unit to a SA alkylation unit. This disclosure also relates to converted SA alkylation units and alkylation processes performed in the converted SA alkylation units.

The present invention provides a novel method for producing hydrogen fluoride which can suppress the occurrence of the pasty state over the whole process of producing hydrogen fluoride, reduce the problem of corrosion caused by sulfuric acid, and improve energy efficiency of the process. A method for producing hydrogen fluoride by reacting calcium fluoride and sulfuric acid comprises: (a) mixing and reacting calcium fluoride and sulfuric acid such that a mixture comprising calcium fluoride particles and sulfuric acid substantially maintains a form of particulate to obtain hydrogen fluoride while supplying sulfuric acid to the calcium fluoride particles at a flow rate of 0.002 to 1 mol/min relative to 1 mol of calcium fluoride to such an amount that a molar ratio of sulfuric acid/calcium fluoride is 0.9 to 1.1.

The present application discloses compositions comprising hydrogen fluoride and fluorinated compounds (e.g., hydrochlorofluorocarbons), wherein the fluorinated compound is present in the composition in an amount effective to form an azeotrope composition or azeotrope-like composition with the hydrogen fluoride.

The present invention relates to a high purity synthetic fluorite (CaF.sub.2). The present invention further relates to a process and an apparatus for preparing said high purity synthetic fluorite (CaF.sub.2), classified as acid grade, starting from fluorosilicic acid H.sub.2SiF.sub.6 (FSA) and calcium carbonate (CaCO.sub.3). Finally, the present invention relates to the use of said high purity synthetic fluorite (CaF.sub.2) in the industrial production of hydrofluoric acid.

Reactions are disclosed in which phosphine and hydrogen fluoride are reacted to produce a phosphorus pentafluoride containing gas according the stoichiometry:
PH.sub.3+4F.sub.2.fwdarw.PF.sub.5+3HF Further reaction using the phosphorus pentafluoride to produce lithium hexafluorophosphate are also disclosed.

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.

Embodiments of the invention provide a method for atomic layer etching (ALE) of a substrate. According to one embodiment, the method includes providing a substrate, and exposing the substrate to hydrogen fluoride (HF) gas and a boron-containing gas to etch the substrate. According to another embodiment, the method includes providing a substrate containing a metal oxide film, exposing the substrate to HF gas to form a fluorinated surface layer on the metal oxide film, and exposing the substrate to a boron-containing gas to remove the fluorinated surface layer from the metal oxide film. The exposures may be repeated at least once to further etch the metal oxide film.

This disclosure relates to methods of converting an HF alkylation unit which utilizes HF as a reaction catalyst to a sulfuric acid alkylation unit which utilizes sulfuric acid as a reaction catalyst. This disclosure also relates to a segmented sulfuric acid settler for separating a sulfuric acid phase from a hydrocarbon phase. This disclosure also relates to methods of converting a vertical HF acid settler to a segmented sulfuric acid settler. This disclosure also relates to converted sulfuric acid alkylation units and alkylation processes performed in the converted sulfuric acid alkylation units.