An oxidative treatment process, e.g., oxidative desulfurization or denitrification, is provided in which the oxidant is produced in-situ using an aromatic-rich portion of the original liquid hydrocarbon feedstock. The process reduces or replaces the need for the separate introduction of liquid oxidants such as hydrogen peroxide, organic peroxide and organic hydroperoxide in an oxidative treatment process.

The invention relates to a method for cleaning hydrocarbon mixtures, in which a contaminated hydrocarbon mixture comprising hydrocarbons having three to eight carbon atoms is at least partly freed of impurities by contacting with a solid sorbent, wherein the hydrocarbon mixture is exclusively in the liquid state during contact with the sorbent. The object of the invention is to specify a process for cleaning liquid C.sub.3 to C.sub.8 hydrocarbon mixtures, which is based on a readily available but non-carcinogenic sorbent and which achieves better purities compared to traditional molecular sieves. This object is achieved by using, as sorbents, solid materials of the following composition: copper oxide: 10% to 60% by weight (calculated as CuO); zinc oxide: 10% to 60% by weight (calculated as ZnO); aluminum oxide: 10% to 30% by weight (calculated as Al.sub.2O.sub.3); other substances: 0% to 5% by weight. Materials of this kind are otherwise used as catalysts in methanol synthesis.

The invention relates to a method for cleaning hydrocarbon mixtures, in which a contaminated hydrocarbon mixture comprising hydrocarbons having three to eight carbon atoms is at least partly freed of impurities by contacting with a solid sorbent, wherein the hydrocarbon mixture is exclusively in the liquid state during contact with the sorbent. The object of the invention is to specify a process for cleaning liquid C.sub.3 to C.sub.8 hydrocarbon mixtures, which is based on a readily available but non-carcinogenic sorbent and which achieves better purities compared to traditional molecular sieves. This object is achieved by using, as sorbents, solid materials of the following composition: copper oxide: 10% to 60% by weight (calculated as CuO); zinc oxide: 10% to 60% by weight (calculated as ZnO); aluminum oxide: 10% to 30% by weight (calculated as Al.sub.2O.sub.3); other substances: 0% to 5% by weight. Materials of this kind are otherwise used as catalysts in methanol synthesis.

A method of desulfurizing a liquid hydrocarbon having the steps of: adding a liquid hydrocarbon to a vessel, the hydrocarbon having a sulfur content; adding a catalyst and an oxidizer to create a mixture; oxidizing at least some of the sulfur content of the liquid hydrocarbon to form oxidized sulfur in the liquid hydrocarbon; separating the liquid hydrocarbon from the mixture; and removing at least some of the oxidized sulfur from the liquid hydrocarbon. Such methods can be carried out by batch or continuously. Systems for undertaking such methods are likewise disclosed.

A method of desulfurizing a liquid hydrocarbon having the steps of: adding a liquid hydrocarbon to a vessel, the hydrocarbon having a sulfur content; adding a catalyst and an oxidizer to create a mixture; oxidizing at least some of the sulfur content of the liquid hydrocarbon to form oxidized sulfur in the liquid hydrocarbon; separating the liquid hydrocarbon from the mixture; and removing at least some of the oxidized sulfur from the liquid hydrocarbon. Such methods can be carried out by batch or continuously. Systems for undertaking such methods are likewise disclosed.

Methods for processing pyrolysis oil employs two or more of the following steps: A first separation creates (a) a lighter fraction and heavier fraction, (b) subjecting the lighter fraction to distillation and (c) subjecting the heavy fraction to removal of at least one of sulfur and nitrogen.

Methods for processing pyrolysis oil employs two or more of the following steps: A first separation creates (a) a lighter fraction and heavier fraction, (b) subjecting the lighter fraction to distillation and (c) subjecting the heavy fraction to removal of at least one of sulfur and nitrogen.

Embodiments of apparatuses and methods for conversion of mercaptans are provided. In one example, an apparatus comprises a vessel that is capable to receive a feed stream that comprises liquid hydrocarbons and the mercaptans. The vessel comprises a catalyst bed section that is capable of contacting the feed stream with a catalyst in the presence of oxygen (O.sub.2) and caustic at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened liquid hydrocarbon-containing stream. A coalescing bed section is capable to coalesce and separate at least a portion of the caustic from the caustic-containing, sweetened liquid hydrocarbon-containing stream for forming a caustic-depleted, sweetened liquid hydrocarbon-containing product stream.

Embodiments of apparatuses and methods for conversion of mercaptans are provided. In one example, an apparatus comprises a vessel that is capable to receive a feed stream that comprises liquid hydrocarbons and the mercaptans. The vessel comprises a catalyst bed section that is capable of contacting the feed stream with a catalyst in the presence of oxygen (O.sub.2) and caustic at reaction conditions effective to oxidize the mercaptans and form a caustic-containing, sweetened liquid hydrocarbon-containing stream. A coalescing bed section is capable to coalesce and separate at least a portion of the caustic from the caustic-containing, sweetened liquid hydrocarbon-containing stream for forming a caustic-depleted, sweetened liquid hydrocarbon-containing product stream.

An oxidative treatment process, e.g., oxidative desulfurization or denitrification, is provided in which the oxidant is produced in-situ using an aromatic-rich portion of the original liquid hydrocarbon feedstock. The process reduces or replaces the need for the separate introduction of liquid oxidants such as hydrogen peroxide, organic peroxide and organic hydroperoxide in an oxidative treatment process.