A process to remove H.sub.2S from a stream comprising the steps of adding Melamine cyanurate, optionally a silica nanoparticle composition, and optionally a triazine. The stream is selected from the group consisting of Oil streams, Gas streams, CO.sub.2 point source purification streams and Geothermal Energy System streams.

A method of removing metals and amines from crude oil comprising adding an effective metal removing amount of one or more hydroxycarboxylic acids selected from lactic acid and malic acid and salts thereof to said crude oil; adding wash water to said crude oil; mixing said crude oil, acid and wash water to form an emulsion; and resolving said emulsion into an aqueous phase and crude oil having a reduced metals content.

A method of removing metals and amines from crude oil comprising adding an effective metal removing amount of one or more hydroxycarboxylic acids selected from lactic acid and malic acid and salts thereof to said crude oil; adding wash water to said crude oil; mixing said crude oil, acid and wash water to form an emulsion; and resolving said emulsion into an aqueous phase and crude oil having a reduced metals content.

A process, a system, and an apparatus for separation of an oxygenate from a stream is provided. More specifically, a stream comprising the oxygenate is introduced to a quench tower along with a caustic outlet stream comprising a metal salt. Contact between the oxygenate and the metal salt results in conversion of a portion of the oxygenate into a derivative salt. The derivative salt and unconverted oxygenate are condensed by quenching and substantially removed from the quench tower as an oxygenate outlet stream. The gaseous components of the stream, minus a substantial portion of the oxygenate, are removed from the quench tower as a quench outlet stream.

A process, a system, and an apparatus for separation of an oxygenate from a stream is provided. More specifically, a stream comprising the oxygenate is introduced to a quench tower along with a caustic outlet stream comprising a metal salt. Contact between the oxygenate and the metal salt results in conversion of a portion of the oxygenate into a derivative salt. The derivative salt and unconverted oxygenate are condensed by quenching and substantially removed from the quench tower as an oxygenate outlet stream. The gaseous components of the stream, minus a substantial portion of the oxygenate, are removed from the quench tower as a quench outlet stream.

A process for purifying a synthetic crude oil stream includes providing a synthetic crude oil stream, washing the synthetic crude oil stream with a first aqueous washing solution at a first temperature in order to obtain a first purified synthetic crude oil stream, and washing the first purified synthetic crude oil stream with a second aqueous washing solution at a second temperature in order to obtain a second purified synthetic crude oil stream. The first aqueous washing solution is basic, the second aqueous washing solution is acidic, and the second temperature is lower than the first temperature. A process for producing synthetic crude oil includes producing a synthetic crude oil stream, preferably by depolymerization of plastic material, in particular plastic waste, and purifying the synthetic crude oil stream.

A process for purifying a synthetic crude oil stream includes providing a synthetic crude oil stream, washing the synthetic crude oil stream with a first aqueous washing solution at a first temperature in order to obtain a first purified synthetic crude oil stream, and washing the first purified synthetic crude oil stream with a second aqueous washing solution at a second temperature in order to obtain a second purified synthetic crude oil stream. The first aqueous washing solution is basic, the second aqueous washing solution is acidic, and the second temperature is lower than the first temperature. A process for producing synthetic crude oil includes producing a synthetic crude oil stream, preferably by depolymerization of plastic material, in particular plastic waste, and purifying the synthetic crude oil stream.

Aqueous treatment compositions for crude oil and/or petroleum distillates to remove sulfur compounds therefrom and treatment methods using such compositions are disclosed. The composition has less than 0.5% wt/wt di- or tri-benzohydroxy compound, a strong base, less than 1% wt/wt divalent metal gluconate, a balance of water, and a pH that is 9 or greater. The treatment method includes adding said treatment composition to crude oil or a petroleum distillate to form a mixture having 0.001% to 0.02% wt di- or tri-benzohydroxy compound/wt oil and 0.001% to 0.03% wt divalent metal gluconate/wt oil and mixing the same together.

Aqueous treatment compositions for crude oil and/or petroleum distillates to remove sulfur compounds therefrom and treatment methods using such compositions are disclosed. The composition has less than 0.5% wt/wt di- or tri-benzohydroxy compound, a strong base, less than 1% wt/wt divalent metal gluconate, a balance of water, and a pH that is 9 or greater. The treatment method includes adding said treatment composition to crude oil or a petroleum distillate to form a mixture having 0.001% to 0.02% wt di- or tri-benzohydroxy compound/wt oil and 0.001% to 0.03% wt divalent metal gluconate/wt oil and mixing the same together.