The present invention provides an exhaust gas purification catalyst provided with: a substrate of wall flow structure in which inlet cells and outlet cells are partitioned by porous partition walls; and a catalyst layer disposed at least inside the partition wall and including a catalyst body. The catalyst layer satisfies the following conditions: (1) the pore volume of pores no larger than 5 m, as measured in accordance with a mercury intrusion technique, is 24000 mm.sup.3 or greater per L of volume of the substrate; and (2) a permeability coefficient measured by a Perm porometer is 0.6 m.sup.2 to 4.4 m.sup.2.

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.

Disclosed is an apparatus for decomposing low-concentration volatile organic compounds, which includes: an adsorption unit configured to adsorb a volatile organic compound; a heated air supply unit configured to supply a heated air to the adsorption unit; an oxidation decomposing catalyst unit configured to decompose a volatile organic compound detached from the adsorption unit; and an ozone supply unit configured to supply an ozone to the oxidation decomposing catalyst unit. The apparatus may maximize an exchange cycle semi-permanently by adsorbing low-concentration VOC under a high-flow condition and then detaching VOC within a short time and also by recycling an adsorption filter. In addition, the apparatus may effectively decompose VOC substances detached by a low flow into carbon dioxide and water under a condition with most excellent oxidation decomposition efficiency by using an oxidation decomposing catalyst filter.

An exhaust gas treatment apparatus which includes a denitration device, a dust collector, and a desulfurization device in order, respectively, in a flow path of exhaust gas discharged from a boiler, wherein a heavy-metal component removal device is provided in the exhaust gas flow path between the dust collector and the desulfurization device. This device is provided with: an absorption tower including a nozzle which sprays acidic absorption liquid on the exhaust gas, a tank which stores liquid which has absorbed a heavy metal, and a pump which supplies the nozzle with the liquid in the tank; a neutralizing tank which neutralizes the liquid drawn from the absorption tower; and a separator which separates the neutralized liquid into a solid and a liquid component. Since a small amount of heavy metal can be removed in the absorption tower, re-emission of the heavy metal by the desulfurization device is prevented.

A catalyst for oxidising ammonia comprises a selective catalytic reduction (SCR) catalyst and a composite heterogeneous extruded honeycomb having longitudinally extending parallel channels, which channels being defined in part by channel walls having a total longitudinal length, wherein the channel walls comprise a pore structure including a periodic arrangement of porous cells embedded in an inorganic matrix component, at least some of which porous cells are defined at least in part by an active interface layer of a catalytically active material comprising a precious metal supported on particles of a support material.

A system for use in selective catalytic reduction reactor is disclosed. The system may include a catalyst bed and a screen located close to the catalyst bed in a manner so that flow of flue gas to the catalyst bed contacts the screen before it contacts the catalyst bed. The screen may be adapted to support a weight of at least 400 pounds above the catalyst bed so that the weight is not imposed on the catalyst. The screen may have a plurality of holes across its surface in a manner so that the screen is adapted to change the velocity distribution of the flue gas as it flows through the screen.

Ceramic candle filter and use of the filter in the removal of particulate matter in form of soot, ash, metals and metal compounds, together with hydrocarbons and optionally nitrogen oxides being present in process off-gas or engine exhaust gas, wherein a noble metal comprising catalyst is arranged on the permeation side of the filter and/or on the dispersion side of the filter and/or within wall of the filter, said noble metal comprising catalyst contains a noble metal in an amount of between 20 and 1000 ppm/weight of the filter.

The present disclosure provides a method for recycling soil contaminated with mercury and dioxin. The method includes: desorbing mercury and dioxin from the contaminated soil by an indirect rotary furnace; condensing the mercury and discharging it by a condensing and discharging unit; and a secondary indirect burner for decomposing dioxin at a high temperature, so as for the concentration of the contaminants in the exhaust being examined to meet regulation standards and the treated soil to meet the current regulations. The present disclosure also provides an apparatus for recycling contaminated soil containing mercury and dioxin.

In the plugged honeycomb structure, 30% or more of first intersection portions in which a first partition wall intersects a second partition wall are first specific intersection portions in which a diameter of a maximum inscribed circle drawn in the first intersection portion is a specific size for a shortest distance between an inflow cell and an outflow cell, and 30% or more of non-first intersection portions other than the first intersection portions are non-first specific intersection portions in which a diameter of a maximum inscribed circle drawn in a non-first intersection portion is a specific size for a shortest distance between the inflow cells or the outflow cells.

A catalyst support material (D-CZMLA) with oxygen storage capacity corresponds to the formula vD:x(Ce.sub.1-wZr.sub.wO.sub.2):yM:zL:(1-v-x-y-z)Al.sub.2O.sub.3, wherein w is a molar ratio between 0.1-0.8 and v, x, y, and z are weight ratios, such that v is between 0.005-0.15, x is between 0.05-0.80, and y and z are between 0.001-0.10. M is an interactive promoter for oxygen storage, L is a stabilizer (L) for the Al.sub.2O.sub.3 support; and D is an oxidizing dopant. The catalyst support material can be incorporated into a wash coat that combines platinum group metals (PGM), an adhesive, and a mixture of ()RE-CeZrO.sub.2+()CZMLA+(1)RE-Al.sub.2O.sub.3, wherein RE-CeZrO.sub.2 is a rare earth element stabilized ceria zirconia having a weight ratio () between 0-0.7; CZMLA is the doped catalyst support material having a weight ratio () between 0.2-1, such that (+)1; and RE-Al.sub.2O.sub.3 is rare earth element stabilized alumina having a weight ratio equal to (1).