A self-activating hydroprocessing catalyst for treating heavy hydrocarbon feedstocks is further activated by contacting the self-activating catalyst with steam. The steam may be added to the heavy hydrocarbon feedstock prior to contacting with the self-activating catalyst or may be added to a reactor vessel containing the self-activating catalyst.

A fluorination catalyst such as a chromium oxide-based fluorination catalyst may be activated or reactivated by contacting the catalyst. with a source of reactive fluorine, for example nitrogen trifluoride (NF3) or fluorine (F2). Fluorinated compounds may be prepared by the gas phase reaction of hydrogen fluoride (HF) with various substrates such as chlorinated compounds. A number of metal oxide-based catalysts have been developed for this purpose.

A fluorination catalyst such as a chromium oxide-based fluorination catalyst may be activated or reactivated by contacting the catalyst. with a source of reactive fluorine, for example nitrogen trifluoride (NF3) or fluorine (F2). Fluorinated compounds may be prepared by the gas phase reaction of hydrogen fluoride (HF) with various substrates such as chlorinated compounds. A number of metal oxide-based catalysts have been developed for this purpose.

Processes for regenerating an at least partially deactivated catalyst that can include a Group (10) element, an inorganic support, and a contaminant. The Group (10) element can have a concentration of from 0.06 wt % to 6 wt %, based on the weight of the inorganic support. The process can include (I) heating the deactivated catalyst using a heating gas mixture that includes H.sub.2O at a concentration >5 mol %, based on the total moles in the mixture to produce a precursor catalyst. The process can also include (II) providing an oxidative gas that includes ?5 mol % of H.sub.2O, based on the total moles in the oxidative gas, and (III) contacting the precursor catalyst at an oxidizing temperature with the oxidative gas for a duration of at least 30 seconds to produce an oxidized precursor catalyst. The process can also include (IV) obtaining a regenerated catalyst from the oxidized precursor catalyst.

Processes for regenerating an at least partially deactivated catalyst that can include a Group (10) element, an inorganic support, and a contaminant. The Group (10) element can have a concentration of from 0.06 wt % to 6 wt %, based on the weight of the inorganic support. The process can include (I) heating the deactivated catalyst using a heating gas mixture that includes H.sub.2O at a concentration >5 mol %, based on the total moles in the mixture to produce a precursor catalyst. The process can also include (II) providing an oxidative gas that includes ?5 mol % of H.sub.2O, based on the total moles in the oxidative gas, and (III) contacting the precursor catalyst at an oxidizing temperature with the oxidative gas for a duration of at least 30 seconds to produce an oxidized precursor catalyst. The process can also include (IV) obtaining a regenerated catalyst from the oxidized precursor catalyst.

A composite comprises a carbonaceous and a metallic nanotube conjugated with a carbonaceous support. The composite may be used to remove contaminants from water.

A composite comprises a carbonaceous and a metallic nanotube conjugated with a carbonaceous support. The composite may be used to remove contaminants from water.

The present invention provides a process for the preparation of a (hydro)(chloro)fluoroalkene by contacting a reagent stream comprising a hydrochlorofluoroalkane with a catalyst in a reactor to dehydrochlorinate at least a portion of the hydrochlorofluoroalkane to produce a product stream comprising the (hydro)(chloro)fluoroalkene and hydrogen chloride (HCl), wherein the catalyst is selected from the group consisting of metal oxide catalysts, metal halide catalysts, zero-valent metal catalysts, carbon-based catalysts and mixtures thereof, and wherein (i) the catalyst is chlorinated prior to contacting it with the reagent stream comprising the hydrochlorofluoroalkane; and/or (ii) the contacting step is carried out in the presence of a HCl co-feed.

The present invention provides a process for the preparation of a (hydro)(chloro)fluoroalkene by contacting a reagent stream comprising a hydrochlorofluoroalkane with a catalyst in a reactor to dehydrochlorinate at least a portion of the hydrochlorofluoroalkane to produce a product stream comprising the (hydro)(chloro)fluoroalkene and hydrogen chloride (HCl), wherein the catalyst is selected from the group consisting of metal oxide catalysts, metal halide catalysts, zero-valent metal catalysts, carbon-based catalysts and mixtures thereof, and wherein (i) the catalyst is chlorinated prior to contacting it with the reagent stream comprising the hydrochlorofluoroalkane; and/or (ii) the contacting step is carried out in the presence of a HCl co-feed.

The present invention relates to a fluorination process, comprising: an activation stage comprising contacting a fluorination catalyst with an oxidizing agent-containing gas flow for at least one hour; and at least one reaction stage comprising reacting a chlorinated compound with hydrogen fluoride in gas phase in the presence of the fluorination catalyst, so as to produce a fluorinated compound.