A novel one-pot solvothermal reaction based on urea hydrolysis to synthesize single crystals of the Zn(NH.sub.3)(CO.sub.3) inorganic helical framework and its applications in selective CO.sub.2 separation.

Systems and methods for producing a product gas are provided. In one embodiment, a system includes at least one separation bed to separate adsorbable components from a gas source, a valving means to selectively direct gas from the gas source to the at least one separation bed, at least one sensing device associated with the at least one separation bed to sense the progress of an adsorption zone within the separation bed, and a controller. The controller includes logic to read the output of the at least one sensing device and control the gas separation process based on the progress of the adsorption zone.

The present invention provides a refrigerating and freezing device. A first sealed space and a second sealed space are disposed in a storage space inside the refrigerating and freezing device. The refrigerating and freezing device is further provided with a nitrogen generation device, which comprises an adsorption device and an air compressor that supplies compressed air for the adsorption device. The adsorption device utilizes the compressed air to prepare nitrogen that is provided for the first sealed space and an oxygen-enriched gas that is provided for the second sealed space. The freshness preservation capability of the first sealed space is improved. The bioactivity of food in the second sealed space is guaranteed.

An apparatus for the production of air gases by the cryogenic separation of air can include a cold box having a heat exchanger, and a system of columns; a pressure monitoring device; and a controller. The cold box can be configured to receive a purified and compressed air stream under conditions effective for cryogenically separating the air stream to form an air gas product. The apparatus may also include means for transferring the air gas product from the cold box to an air gas pipeline. The pressure monitoring device is configured to monitor the pipeline pressure, and the controller is configured to determine whether to operate in a power savings mode or a variable liquid production mode. By operating the apparatus in a dynamic fashion, a power savings and/or additional high value cryogenic liquids can be realized in instances in which the pipeline pressure deviates from its highest value.

The invention relates to a gas purifier that removes moisture and oxygen from inert gases and reducing gases, for example, at sub-atmospheric pressures. The purifier can remove part per million levels of moisture in a gas stream to less than 100 parts per trillion by volume, and has a low pressure drop and a sharp breakthrough curve.

Described herein is a method for detecting steady state ammonia slip for a motor vehicle having an internal combustion engine and an emissions control system. The emissions control system includes a selective catalytic reduction (SCR) device, a NOx sensor, and a controller. The controller executes a method for ammonia slip detection that includes determining if the SCR device is at steady state, comparing a NOx measurement from the NOx sensor with a predicted NOx value. If the NOx measurement exceeds the predicted NOx value by a threshold, perturbing a reductant injection, the perturbation having a selected magnitude and a selected duration. The method also includes measuring a NOx value resulting from the perturbation and computing a gradient thereof relative to the measured NOx, and ascertaining if a gradient of the NOx resulting from the perturbation exceeds a threshold and identifying a reductant slip condition if so.

A gas inerting system employs a carbon dioxide separation unit to remove carbon dioxide and water from an oxygen depleted gas stream generated from a catalytic oxidation unit and subsequently provides a nitrogen rich inerting gas to a fuel tank and/or to a cargo hold. A method of producing an inert gas passes an oxygen depleted gas stream from a catalytic oxidation unit through a carbon dioxide separation unit and provides a nitrogen rich inerting gas for fuel tank inerting and/or cargo hold fire suppression.

In embodiments of the present disclosure, a CMS hollow fiber membranes may be prepared to have an ultrathin (e.g. 2 microns or less) separation layer. A precursor hollow fiber may be prepared as dual layer fibers having a thin sheath layer and a core layer. During pyrolysis, the sheath layer is transformed into an ultrathin separation layer. Porosity of the core layer substrate is well-maintained during pyrolysis, thereby enabling high permeance of the CMS hollow fiber membrane. Additionally, in some embodiments, the sheath layer of the precursor hollow fibers may be hybridized prior to pyrolysis. By hybridizing the sheath layer prior to pyrolysis, a CMS hollow fiber may having an improved separation factor, including for example increased carbon dioxide/methane selectivity, may be provided.

A non-cryogenic system for producing high-purity nitrogen is connected to a coiled-tubing unit. The nitrogen is produced by passing compressed ambient air through two polymeric membrane modules connected in series. The output of the second module is a stream of high-purity nitrogen, which is conveyed into a coiled tube. The nitrogen can be used for inerting the interior of the tube, or the coiled tube can be inserted into an oil well, for delivering nitrogen into the well. The use of nitrogen in a coiled tube helps to prevent corrosion in the tube.

A method and apparatus for generation of fluorine gas (F2) in situ at the point of use is provided. The portable fluorine generator includes a dilution system disposed within a housing and operable to mix a feed gas comprising fluorine with an inert gas. The portable fluorine generator further includes a plasma reactor unit disposed within the housing and operable to separate fluorine (F2) from the feed gas comprising fluorine.