A portable pressure swing adsorption method and system for fuel gas conditioning. A fuel gas conditioning system includes a pressure swing adsorption (PSA) system fluidly coupled to a rich gas stream, the PSA system including a plurality of adsorbent beds and configured to condition the rich natural gas stream and produce therefrom a high-quality fuel gas and gaseous separated heavier hydrocarbons, a product end of the adsorbent beds fluidly coupled to a fuel gas line, wherein the high-quality fuel gas is discharged from the product end and supplied to the fuel gas line, and a feed end of the adsorbent beds configured to be fluidly coupled to the rich natural gas stream or a raw natural gas stream, wherein the produced gaseous separated heavier hydrocarbons are recirculated into the rich natural gas stream or the raw natural gas stream.

The present invention provides a method for purifying carbon dioxide gas characterized in that carbon dioxide gas containing at least one of 3-methylmercaptopropionaldehyde and acrolein is contacted with activated carbon to remove at least one of the 3-methylmercaptopropionaldehyde and acrolein. The present invention provides also a method for producing methionine comprising the purification step of the recovered carbon dioxide.

Methods and systems are provided for diagnosing degradation and/or alteration in an evaporative emission control system of a vehicle. In one example, a method may include, during a refueling, monitoring a fuel tank pressure and a fuel fill level, and detecting a presence or an absence of a fuel vapor canister of the EVAP system based on a change in fuel tank pressure with an increase in fuel level.

Methods and systems are provided for diagnosing degradation and/or alteration in an evaporative emission control system of a vehicle. In one example, a method may include, during a refueling, monitoring a fuel tank pressure and a fuel fill level, and detecting a presence or an absence of a fuel vapor canister of the EVAP system based on a change in fuel tank pressure with an increase in fuel level.

The present description provides low DBL bleed emission performance properties that allows the design of evaporative fuel emission control systems that are simpler and more compact than those possible by prior art by inclusion of a vent-side volume comprising a parallel passage adsorbent such as a carbon honeycomb with narrow channel width and low cell pitch.

Disclosed are a composite oxide which is capable of maintaining a large volume of pores even used in a high temperature environment, and which has excellent heat resistance and catalytic activity, as well as a method for producing the composite oxide and a catalyst for exhaust gas purification employing the composite oxide. The composite oxide contains cerium and at least one element selected from aluminum, silicon, or rare earth metals other than cerium and including yttrium, at a mass ratio of 85:15 to 99:1 in terms oxides, and has a property of exhibiting a not less than 0.30 cm.sup.3/g, preferably not less than 0.40 cm.sup.3/g volume of pores with a diameter of not larger than 200 nm, after calcination at 900° C. for 5 hours, and is suitable for a co-catalyst in a catalyst for vehicle exhaust gas purification.

Provided an air cleaning system, which includes: a first reactor which has a first inlet and a first outlet and in which a channel is formed; a first moisture adsorption filter and a first water-soluble gas pollutant adsorption filter that are provided inside the first reactor and are provided so that a gas passes therethrough sequentially while flowing along the channel from the first inlet to the first outlet; a plurality of first magnetrons that are provided at a lateral portion of the first reactor so as to correspond respectively to the first moisture adsorption filter and the first water-soluble gas pollutant adsorption filter and selectively apply microwaves to the first moisture adsorption filter and the first water-soluble gas pollutant adsorption filter; and a heat exchanger that receives hot air containing a water-soluble gas pollutant and moisture, both of which are desorbed from the first moisture adsorption filter and the first water-soluble gas pollutant adsorption filter and are discharged by the first outlet, condenses the moisture into water, and dissolves and discharges the water-soluble gas pollutant in the condensed water. According to the present invention, the air cleaning system can unify a dehumidifying process and a water-soluble gas pollutant removing process to simplify an air cleaning process, recover and recycle waste heat by introducing microwaves and the heat exchanger so as to contribute to energy saving, and be used semi-permanently without a need to periodically replace a filter.

Structured adsorbent beds comprising a high cell density substrate, such as greater than about 1040 cpsi, and a coating comprising adsorbent particles, such as DDR and a binder, such as SiO.sub.2 are provided herein. Methods of preparing the structured adsorbent bed and gas separation processes using the structured adsorbent bed are also provided herein.

A solvent and method for removing carbon dioxide from a gaseous mixture flow with high carbon dioxide partial pressures are disclosed. The solvent includes a secondary or tertiary amine, an amine activator, a physical solvent (e.g., thioalkanol), and a carbonate buffer. The solvent contains less than about 60% by weight of water and is in a single liquid phase.

Ceramic candle filter and use of the filter in the removal of particulate matter in form of soot, ash, metals and met-al compounds, together with hydrocarbons and nitrogen oxides being present in process off-gas or engine exhaust gas, the filter includes a combined SCR and oxidation catalyst being arranged on the dispersion side and within wall of the filter; and a palladium including catalyst arranged on the permeation side and within wall of the filter facing the permeation side.