摘要:
Hydrocarbon (HC) traps are disclosed. The HC trap may include a first zeolite material having an average pore diameter of at least 5.0 angstroms and configured to trap hydrocarbons from an exhaust stream and to release at least a portion of the trapped hydrocarbons at a temperature of at least 225° C. The HC trap may also include a second zeolite material having an average pore diameter of less than 5.0 angstroms or larger than 7.0 angstroms. One or both of the zeolite materials may include metal ions, such as transition, Group 1A, or platinum group metals. The HC trap may include two or more discrete layers of zeolite materials or the two or more zeolite materials may be mixed. The multiple zeolite HC trap may form coke molecules having a relatively low combustion temperature, such as below 500° C.
摘要:
The present invention relates to a catalyst, which may be used in selective catalytic reduction (SCR), said catalyst comprising one or more zeolites of the BEA structure type, one or more zeolites of the CHA structure type, and optionally one or more zeolites of the MFI structure type, wherein at least part of the one or more zeolites of the BEA structure type contain iron (Fe), wherein at least part of the one or more zeolites of the CHA structure type contain copper (Cu), and wherein at least part of the optional one or more zeolites of the MFI structure type contain iron (Fe). Furthermore, the present invention concerns an exhaust gas treatment system comprising said catalyst as well as a process for the treatment of a gas stream comprising NOx using said catalyst as well.
摘要:
A catalyst washcoat is provided having a molecular sieve with a CHA crystal structure; about 0.5 to about 5.0 mol % phosphorus; and SiO2 and Al2O3 in a mole ratio of about 5 to about 40. The washcoat includes one or more promoters or stabilizers, and may be applied to a monolith substrate to produce a catalytically active article.
摘要:
This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having RTH topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation structuring agents.
摘要:
This disclosure relates to new crystalline microporous solids (including silicate- and aluminosilicate-based solids), the compositions comprising 8 and 10 membered inorganic rings, particularly those having HEU topologies having a range of Si:Al ratios, methods of preparing these and known crystalline microporous solids using certain quaternized imidazolium cation structuring agents.
摘要:
A method for preparing molecular sieves with a Linde Type A (LTA) topology structure, and molecular sieves obtained thereby are described wherein a structure directing agent comprising a triquaternary cation is contacted with a source of a first oxide of a first tetravalent element or a source of a first oxide of a trivalent element; and a source of an oxide of a pentavalent elements.
摘要:
A metal-doped or metal-exchanged zeolite is disclosed, wherein the doping metal is present in the zeolite in the form of individual atoms i.e. as monomeric and/or dimeric species. Further, a process for the preparation of such a metal-doped or metal-exchanged zeolite is disclosed. The metal-doped zeolites are useful, in particular, as catalysts for the reduction of nitrogen oxides.
摘要:
The present invention relates to a copper-containing KFI-type zeolite, wherein the zeolite contains 1 to 4.5 wt.-% copper. The invention is also directed towards a method for producing the copper-containing zeolite according to the invention as well as towards the use of the zeolite in SCR catalysis. Further subjects of the invention are a washcoat which contains the zeolite according to the invention, an SCR catalyst which contains the zeolite according to the invention as well as an exhaust-gas cleaning system which comprises the SCR catalyst.
摘要:
Disclosed are a catalyst comprising (A) an aluminosilicate molecular sieve comprising a ferrierite phase and (B) a hydrogenation metal component, and a hydroalkylation process using the catalyst. The catalyst and the hydroalkylation process can be used in the production of phenol and/or cyclohexanone from benzene hydroalkylation.
摘要:
The present invention relates to an organotemplate-free synthetic process for the production of a zeolitic material having a BEA framework structure comprising YO2 and optionally comprising X2O3, wherein said process comprises the steps of (1) preparing a mixture comprising seed crystals and at least one source for YO2; and (2) crystallizing the mixture; wherein Y is a tetravalent element, and X is a trivalent element, wherein the zeolitic material optionally comprises at least one alkali metal M, wherein when the BEA framework additionally comprises X2O3, the mixture according to step (1) comprises at least one source for X2O3, and wherein the seed crystals comprise zeolitic material having a BEA framework structure, preferably zeolite Beta.
摘要翻译:本发明涉及一种用于生产具有包含YO 2和任选地包含X 2 O 3的BEA骨架结构的沸石材料的无机模板合成方法,其中所述方法包括以下步骤:(1)制备包含晶种和至少一种 来源为YO2; 和(2)使混合物结晶; 其中Y是四价元素,X是三价元素,其中沸石材料任选地包含至少一种碱金属M,其中当BEA骨架另外包含X 2 O 3时,根据步骤(1)的混合物包含至少一种源 X 2 O 3,并且其中所述晶种包含具有BEA骨架结构的沸石材料,优选沸石β。