Process for cleaning an off-gas containing sulphur oxides (SOx), nitrogen oxides (NOx) and particulate matter employing SOx adsorption and ammonia-SCR in one filtration unit, in particular a filter bag house with one or more catalysed fabric filter assemblies.

A catalyst unit for purifying flue gas, comprising a plurality of platy catalyst elements, wherein the platy catalyst element comprises one flat plate portion and one wavy plate portion, the wavy plate portion has ridges and thalwegs, the platy catalyst elements are stacked each other so that a top of the ridges of the wavy plate portion in one of the platy catalyst elements is in contact with the flat plate portion of another adjacent of the platy catalyst elements and the wavy plate portion secures gas flow paths, the flat plate portion and the wavy plate portion are respectively quadrilateral in view image from normal direction relative to a main face thereof, an edge of the flat plate portion and an edge of the wavy plate portion are connected, and a number of the ridges and a number of the thalwegs are totally not less than 4.

A catalyst bed comprising a ceramic or metallic foam comprising one or more NOx reduction catalysts is described. Further, a method for reducing the concentration of NOx in a dust containing gas stream comprising: a) passing a first gas stream containing NOx into a contacting zone; b) contacting the first gas stream with a ceramic or metallic foam catalyst bed having one or more flow paths through the catalyst bed wherein the ceramic or metallic foam comprises a NOx reduction catalyst to produce a second gas stream with a reduced NOx concentration; and c) passing the second gas stream out of the contacting zone wherein the first gas stream has a dust concentration of at least 5 mg/Nm3 and the second gas stream comprises at least 50% of the amount of dust in the first gas stream.

A honeycomb body having a honeycomb structure and a peripheral skin, the honeycomb structure having walls defining a plurality of cells including peripheral cells disposed directly adjacent to the peripheral skin. One or more of the peripheral cells is at least partially defined by a first wall surface, a second wall surface, and a skin surface portion extending between the first wall surface and the second wall surface. A continuously-varying radius extends from a first tangent to the first wall surface along the skin surface portion and to a second tangent to the second wall surface. Other honeycomb bodies, structures, and extrusion dies for forming honeycomb structures are disclosed.

The present invention relates to an average-density-adjustable structure and more specifically provides a structure the average density of which is adjusted by changing the material of the structure and the size of a void formed therein and which can thereby float on the surface of or in a liquid and can easily bond with or change a material present in a gas or liquid by being equipped with a first material, which is one among an organic catalyst, an inorganic catalyst, a microorganism, and a biomolecule.

A catalyst for treating an exhaust gas comprising SO.sub.2, NO.sub.x and elemental mercury in the presence of a nitrogenous reductant comprises a composition containing oxides of: (i) Molybdenum (Mo) and optionally Tungsten (W); and (ii) Vanadium (V); and (iii) Titanium (Ti); and (iv) Phosphorus (P), wherein, with respect to the total metal atoms in the composition, the composition comprises: (i) Mo in an amount of less than 2 at. %, and optionally up to 9 at. % W; (ii) from 2.5 to 12 at. % V; (iii) from 85 to 96 at. % Ti, and wherein the composition comprises (iv) P in an atomic ratio to the sum of atoms of Mo, W and V of from 1:2 to 3:2. The values expressed must total 100%.

An electrically heated catalyst includes a honeycomb substrate, an electrode, and a joining section. The honeycomb substrate and the joining section include matrices and conductive fillers. The matrices contain borosilicate including at least one of an alkali metal and an alkaline earth metal. The joining section preferably has a softening point lower than that of the honeycomb substrate.

A propulsion element including a catalyzing reactor is disclosed. The catalyzing reactor comprises a reactor entrance and a reactor exit and an internal structure arranged for flowing a reacting medium through the reactor from the reactor entrance to the reactor exit. The reactor structure comprising at least one thin walled reactor channel arranged between the entrance and the exit of the reactor. The channel having a channel wall that includes a catalyst and that defines a flow path, in which channel in use, a catalyzed exothermic reaction takes place in the medium as it flows along the flow path. The at least one channel is looped to have a portion of its flow path that is downstream with respect to the reactor entrance in heat exchanging contact with a portion of a flow path that is that is more upstream with respect to the reactor entrance, so as to transfer heat between a downstream portion of the reacting medium to an upstream portion thereof.

Methods and systems are provided for detecting a missing exhaust catalyst based on water adsorption and related exothermic temperature rise by the catalyst. In one example, a method may include indicating an exhaust catalyst missing in response to an estimated exhaust temperature profile being different from an expected exhaust temperature profile. The estimated exhaust temperature profile may be based on exhaust temperature upstream and downstream of the catalyst.

Visible-light response hybrid aerogel and a preparation method and application thereof in waste gas processing are disclosed. Dicyandiamide is taken as a precursor and is calcined in two times to prepare a carbon nitride nanosheet; the carbon nitride nanosheet is dispersed in water, silver metavanadate quantum dots are subjected to in-situ growth to prepare a silver metavanadate quantum dot/carbon nitride nanosheet composite material; the silver metavanadate quantum dot/carbon nitride nanosheet composite material and graphene oxide carry out hydrothermal reaction, and are then frozen and dried to prepare silver metavanadate quantum dot/carbon nitride nanosheet/graphene hybrid aerogel which is the visible-light response hybrid aerogel. The problems of large reduction dosage, serious secondary pollution, complexity in operation and the like generated when waste gas is processed by a traditional flue gas denitration technology are overcome.