Abstract: An alkylation process system uses an ionic liquid as a catalyst which undergoes an interruption in normal operating condition. A method of maintaining the alkylation process system during the interruption of the normal operating condition requires maintaining a circulation of the ionic liquid through the alkylation process system without interruption.

Abstract: An OBD system that diagnoses on board the condition of NOx adsorber catalysts in diesel engines and that relies on existing mass-produced exhaust gas oxygen sensor, also known as lambda sensor, technology, and the following established phenomena. In a reducing environment, typical exhaust gas oxygen (lambda) sensors have different sensitivities to various reductants, with sensitivity decreasing in this order: H2>CO>short-chain hydrocarbons>long-chain hydrocarbons. In the process of regeneration of the NOx adsorber catalyst, the original reductant may evolve into a different reductant species, e.g., via reactions such as a water-gas shift (WGS), a reforming, a partial oxidation, etc. This leads to a difference in exhaust gas oxygen sensor readings between the inlet to the catalyst and outlet from the catalyst. It has been observed in diesel engine testing that the ability of the NOx adsorber catalyst to perform such a reductant evolution is correlative to the catalyst's NOx reduction capability.

Abstract: An OBD system that diagnoses on board the condition of NOx adsorber catalysts in diesel engines and that relies on existing mass-produced exhaust gas oxygen sensor, also known as lambda sensor, technology, and the following established phenomena. In a reducing environment, typical exhaust gas oxygen (lambda) sensors have different sensitivities to various reductants, with sensitivity decreasing in this order: H2>CO>short-chain hydrocarbons>long-chain hydrocarbons. In the process of regeneration of the NOx adsorber catalyst, the original reductant may evolve into a different reductant species, e.g., via reactions such as a water-gas shift (WGS), a reforming, a partial oxidation, etc. This leads to a difference in exhaust gas oxygen sensor readings between the inlet to the catalyst and outlet from the catalyst. It has been observed in diesel engine testing that the ability of the NOx adsorber catalyst to perform such a reductant evolution is correlative to the catalyst's NOx reduction capability.

Abstract: A method of removing sulfur from a NOx-trap composition positioned downstream and/or on an electric heater in a diesel exhaust system comprises the step of periodically heating the electric heater when the exhaust gas composition is lean, thereby to desorb SOx adsorbed on the NOx trap composition. An exhaust system for carrying out the method comprises an electric heater, a NOx-trap composition positioned downstream and/or on the electric heater and means for controlling the electric heater to periodically heat the NOx-trap composition when the exhaust gas composition is lean, thereby to desorb SOx adsorbed on the NOx-trap composition.

Abstract: A catalyst system includes a three-way catalyst (TWC) mounted underfloor and an engine management system programmed to initiate an enrichment of the exhaust gases exiting the engine with at least one of CO and hydrocarbons and to add secondary air to the exhaust gases in the exhaust passage upstream of the TWC. This periodic enrichment and addition of secondary air causes catalytic oxidation of the at least one of CO and hydrocarbons over the TWC thereby raising the underfloor TWC temperature to at least 550° C., preferably higher, in order to reduce sulphur poisoning of the catalyst and maintain the desired catalytic activity.

Abstract: Engine exhaust gas emissions are cleaned up using apparatus comprising an electrical heater, a first catalyst for oxidizing CO and H2, and a hydrocarbon oxidation catalyst (which may be the same as the first catalyst). Engine management initiates electrical heating upon start-up of the engine, and ensures that there is sufficient CO and H2 and sufficient additional air supplied to the exhaust system, to provide chemical energy in the form of exotherm, whereby the hydrocarbon oxidation catalyst is speeded in reaching light-off temperature.