Treatment of crude oil with basic ionic liquids (ILs), results in scavenging of any hydrochloric acid (HCI) that is present to remove the HCI. The IL is a quaternary ammonium compound having the formula R.sub.4N.sup.+X.sup. or R.sub.3N.sup.+RN.sup.+R.sub.3, where R is independently an alkyl group, an alkylbenzyl group, a hydroxyalkyl group, or a hydroxyalkylbenzyl group, and R is straight or branched and has 1-22 carbon atoms, R is a straight or branched alkylene or oxyalkylene having 1 to 10 carbon atoms, and where X.sup. is selected from the group consisting of hydroxide, carbonate, alkylcarbonate, bicarbonate or alkoxide, where the alkyl group of the alkyl-carbonate or alkoxide, if present, is straight or branched and has 1 to 8 carbon atoms. The ILs are introduced into the crude oil after the refinery desalters and before the crude distillation tower to prevent or inhibit HCI from distilling to the crude tower overhead.

Treatment of crude oil with basic ionic liquids (ILs), results in scavenging of any hydrochloric acid (HCI) that is present to remove the HCI. The IL is a quaternary ammonium compound having the formula R.sub.4N.sup.+X.sup. or R.sub.3N.sup.+RN.sup.+R.sub.3, where R is independently an alkyl group, an alkylbenzyl group, a hydroxyalkyl group, or a hydroxyalkylbenzyl group, and R is straight or branched and has 1-22 carbon atoms, R is a straight or branched alkylene or oxyalkylene having 1 to 10 carbon atoms, and where X.sup. is selected from the group consisting of hydroxide, carbonate, alkylcarbonate, bicarbonate or alkoxide, where the alkyl group of the alkyl-carbonate or alkoxide, if present, is straight or branched and has 1 to 8 carbon atoms. The ILs are introduced into the crude oil after the refinery desalters and before the crude distillation tower to prevent or inhibit HCI from distilling to the crude tower overhead.

A method for removing amine contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.

A method for removing amine contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.

A system for removing mercaptan contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.

A system for removing mercaptan contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.

Disclosed is a method for purifying a composition containing a plastic pyrolysis oil, which method comprises treating with a strong base in the presence of an alcohol. The method is useful for reducing the concentration of heteroelements in said composition with a view to making it compatible for introduction as feedstock in conversion methods such as steam cracking, fluid catalytic cracking, catalytic hydrogenation or hydrocracking.

The invention involves an integrated process in which a hydrocarbon feedstock is treated with a caustic (alkaline) extraction to remove sulfides, disulfides, and mercaptans. These extracted materials are further treated, and are then used to activate hydrotreating catalysts.

The invention involves an integrated process in which a hydrocarbon feedstock is treated with a caustic (alkaline) extraction to remove sulfides, disulfides, and mercaptans. These extracted materials are further treated, and are then used to activate hydrotreating catalysts.

A system for removing contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.