A method for treating exhaust gas from an internal combustion engine including, determining if a steady state condition exist and perturbing a reductant injection corresponding the steady state. Measuring a first and a second NOx values corresponding to the steady state and resulting from the perturbation, and computing a gradient of the NO.sub.x values relative to the steady state respectively. The method also includes comparing the gradient of the second NO.sub.x value with one of the first NO.sub.x value, if the gradient of the first NOx value is within a selected range of the gradient of the second NOx value, identifying poor efficiency operation for the engine and setting an estimated reductant storage at zero. Otherwise if the gradient of the second NOx value exceeds a selected threshold, identifying a reductant slip condition and setting the estimated storage at maximum, if not, making no corrections in estimated storage.

[Summary]

[Problem]

The problem addressed by the present invention lies in providing an exhaust gas purification filter which can efficiently treat particulate matter in exhaust gas.

[Solution]

The present invention provides an exhaust gas purification filter including a substrate comprising a plurality of porous partitions, wherein the partitions form an exhaust gas flow path, a porous catalytic layer is provided on the partitions and the catalytic layer having a thickness of 10 m or greater is provided over at least 20% of the total length of the partitions in the lengthwise direction thereof, and the catalytic layer having a thickness of 10 m or greater is not present on the partitions 15 mm from an outflow side.

A multifunctional microwave plasma and ultraviolet light deodorization treatment unit, which includes: a rapid decomposition device (1), a high frequency plasma electric field (2), a microwave plasma electric field (3), a high intensity ultraviolet radiation field (4), a low temperature plasma electric field (5), a high intensity ozone gas reaction chamber (6), a reaction termination chamber (7) and a clean gas organization chamber (8) sequentially installed inside a horizontal rectangular box which has an elongated body defining a horizontal axis and has a channel cavity therein. The deodorization treatment unit further includes an exhaust gas odor collecting pipe and an odor gas storage cabinet (9) connected to an air pump (10), the air pump (10) is connected to an odor gas inlet of the rapid decomposition device (1), the clean gas organization chamber (8) has one end connected to a clean gas exhaust pipe.

A catalyst coating for use in a hydrolysis catalyst (H-catalyst) for the reduction of nitrogen oxides, a manufacturing method for such a coating, a catalyst structure and its use are described. The H-catalyst includes alkaline compounds, which are capable of adsorbing HNCO and/or nitrogen oxides and which include alkali and alkaline earth metals, lanthanum and/or yttrium and/or hafnium and/or prasedium and/or gallium, and/or zirconium for promoting reduction, such as for promoting the hydrolysis of urea and the formation of ammonia and/or the selective reduction of nitrogen oxides.

Described herein is a desulfurization method for desulfurizing a SCR device treating an exhaust gas. The desulfurization method includes injecting a reductant into the exhaust gas upstream from or into the SCR device and increasing a temperature of the exhaust gas.

A method for treating exhaust gas from an internal combustion engine including, determining if a steady state condition exist and perturbing a reductant injection corresponding the steady state. Measuring a first and a second NOx values corresponding to the steady state and resulting from the perturbation, and computing a gradient of the NO.sub.x values relative to the steady state respectively. The method also includes comparing the gradient of the second NO.sub.x value with one of the first NO.sub.x value, if the gradient of the first NOx value is within a selected range of the gradient of the second NOx value, identifying poor efficiency operation for the engine and setting an estimated reductant storage at zero. Otherwise if the gradient of the second NOx value exceeds a selected threshold, identifying a reductant slip condition and setting the estimated storage at maximum, if not, making no corrections in estimated storage.

Described herein is a desulfurization method for desulfurizing a SCR device treating an exhaust gas. The desulfurization method includes injecting a reductant into the exhaust gas upstream from or into the SCR device and increasing a temperature of the exhaust gas.

Provided is an exhaust gas purification filter including a substrate comprising a plurality of porous partitions, wherein the partitions form an exhaust gas flow path, a porous catalytic layer is provided on the partitions and the catalytic layer having a thickness of 10 m or greater is provided over at least 20% of the total length of the partitions in the lengthwise direction thereof, and the catalytic layer having a thickness of 10 m or greater is not present on the partitions 15 mm from an outflow side.

The present inventive concept relates to a surface-modified zeolite for direct air capture, and more particularly, to a zeolite for carbon dioxide capture whose surface is modified through sodium ion exchange. The zeolite for carbon dioxide capture is prepared by mixing a zeolite support and a supporting solution to form a mixed solution, heating the mixed solution to perform ion exchange, followed by evaporation, washing, drying and calcining. The resulting zeolite for carbon dioxide capture exhibits excellent CO.sub.2 absorption/desorption performance and maintains consistent catalytic activity, allowing for reuse.

A flow-through solid catalyst formed by coating a zeolite material on a metal or ceramic solid substrate. In some embodiments, the solid substrate is formed as flat plates, corrugated plates, or honeycomb blocks.