A transesterification catalyst that is heterogeneous and a method for preparing said transesterification catalyst are provided. The catalyst can be used in a variety of transesterification reactor configurations including CSTR (continuous stirred tank reactors), ebullated (or ebullating) beds or any other fluidized bed reactors, and PFR (plug flow, fixed bed reactors). The catalyst can be used for manufacturing commercial grade biodiesel, biolubricants and glycerin.

Disclosed is an exhaust gas purification catalyst carrier which includes a phosphate salt represented by formula: MPO.sub.4 (wherein M represents Y, La, or Al) or a zirconium phosphate represented by formula ZrP.sub.2O.sub.7; an exhaust gas purification catalyst containing a noble metal at least containing Rh and supported on the carrier; and an exhaust gas purification catalyst product having a catalyst support made of a ceramic or metallic material, and a layer of the exhaust gas purification catalyst, the layer being supported on the catalyst support.

An electrode assembly including a first electrode and a dielectric layer on the first electrode. The dielectric layer comprises a lead-containing compound of the formula PbMgV.sub.2O.sub.7, Pb.sub.2Te.sub.3O.sub.8, PbZnV.sub.2O.sub.7, Na.sub.2PbO.sub.2, PbP.sub.2O.sub.6, PbZnSiO.sub.4, Pb.sub.2In.sub.2Si.sub.2O.sub.9, Pb.sub.6(AsO.sub.4)[B(AsO.sub.4).sub.4], PbAl.sub.2Si.sub.2O.sub.8, K.sub.4PbO.sub.3, Pb.sub.2TiAs.sub.2O.sub.9, Pb.sub.4O(VO.sub.4).sub.2, Rb.sub.4PbO.sub.3, Pb.sub.2V.sub.2O.sub.7, Pb.sub.9Al.sub.8O.sub.21, Nd(Al.sub.3O.sub.6)(Pb.sub.2O.sub.2), Pb.sub.6Co.sub.9(TeO.sub.6).sub.5, Pb.sub.3(B.sub.3O.sub.7)NO.sub.3, a lead-containing oxyhalide of the formula Pb.sub.13(Cl.sub.3O.sub.5).sub.2, Pb.sub.13(Br.sub.3O.sub.5).sub.2, Pb.sub.2OF.sub.2, Pb.sub.2CO.sub.3F.sub.2, Pb(AsO.sub.2).sub.3Cl, Pb.sub.3O.sub.2(OH)Cl, Pb.sub.6(BO.sub.3).sub.3OCl, Pb.sub.2B.sub.5O.sub.9I, Pb.sub.2B.sub.5O.sub.9Br, Pb.sub.2B.sub.5O.sub.9Cl, Pb.sub.5(AsO.sub.3).sub.3Cl, Pb.sub.8Y.sub.6F.sub.32O, Pb(O.sub.2Pb.sub.3).sub.2(BO.sub.3)Br.sub.3, Pb.sub.6LaO.sub.7Cl, a lead-containing phosphate of the formula Pb.sub.2PO.sub.4I, Pb.sub.2InP.sub.3O.sub.11, Pb.sub.2MoP.sub.3O.sub.11, Pb.sub.2Ni(PO.sub.4).sub.2, Pb.sub.2VO(PO.sub.4), K.sub.2Pb(PO.sub.3).sub.4, Pb.sub.3(MoO).sub.3(PO.sub.4).sub.5, Pb.sub.4O(PO.sub.4).sub.2, RbPb(PO.sub.3).sub.3, PbVO.sub.2PO.sub.4, Pb.sub.5(PO.sub.4).sub.3F, Pb.sub.5(PO.sub.4).sub.3Cl, Pb.sub.5(PO.sub.4).sub.3I, PbP.sub.2O.sub.6, or a combination thereof. The electrode assembly can be particularly useful in various electronic devices.

Phosphorus tolerant or resistant three-way catalysts (TWC) are disclosed. The TWC may include a substrate defining a plurality of channels. It may include front and rear washcoat portions overlying the substrate and having respective first and second washcoat loadings, the first washcoat loading being at most 2.0 g/in.sup.3 and less than the second washcoat loading. The front washcoat portion may include a catalyst material supported on a support material comprising a cerium oxide, such as ceria or CZO, or a pre-phosphated material, such as AlPO.sub.4, or CePO.sub.4. In one embodiment, the support material may comprise at least 85 wt. % of a cerium oxide or at least 85 wt. % of a phosphate-containing material. The front portion and the underlying substrate may comprise from 3 to 25 vol. % of the three-way catalyst or the front portion may overly up to an initial 15% of an axial length of the substrate.

Disclosed is a method for synthesizing a sitagliptin intermediate, the method comprising: in the presence of hydrogen and a transition metal catalyst having a chiral phosphine ligand, subjecting a compound of formula II to an asymmetric reductive amination with ammonia or ammonium salt in a proper organic solvent under the condition of adding an acidic additive to produce a compound of formula I, wherein, an R- or S-configuration of a stereocenter is represented by *; the compound of formula I of R configuration can be used to prepare sitagliptin, and a reaction formula is as follows: R.sup.1 and R.sup.2 are each independently selected from hydrogen, C.sub.1-C.sub.12 linear or branched alkyl, C.sub.3-C.sub.12 cycloalkyl, C.sub.2-C.sub.12 alkenyl, C.sub.2-C.sub.12 alkynyl and C.sub.7-C.sub.12 arylalkyl. The method has a high yield and a high ee % value, a mild reaction condition and a low production cost, and is simple to operate, convenient to purify, environmental friendly and suitable for industrial production.

##STR00001##

Disclosed is a method for synthesizing a sitagliptin intermediate, the method comprising: in the presence of hydrogen and a transition metal catalyst having a chiral phosphine ligand, subjecting a compound of formula II to an asymmetric reductive amination with ammonia or ammonium salt in a proper organic solvent under the condition of adding an acidic additive to produce a compound of formula I, wherein, an R- or S-configuration of a stereocenter is represented by *; the compound of formula I of R configuration can be used to prepare sitagliptin, and a reaction formula is as follows: R.sup.1 and R.sup.2 are each independently selected from hydrogen, C.sub.1-C.sub.12 linear or branched alkyl, C.sub.3-C.sub.12 cycloalkyl, C.sub.2-C.sub.12 alkenyl, C.sub.2-C.sub.12 alkynyl and C.sub.7-C.sub.12 arylalkyl. The method has a high yield and a high ee % value, a mild reaction condition and a low production cost, and is simple to operate, convenient to purify, environmental friendly and suitable for industrial production.

##STR00001##

The present invention relates to: a catalyst for glycerin dehydration; a preparation method therefor; and an acrolein preparation method using the catalyst. According to one embodiment of the present invention, the catalyst is used in glycerin dehydration so as to exhibit high catalytic activity, a high yield and high acrolein selectivity, and has a characteristic in which carbon is not readily deposited, thereby having a long lifetime compared with that of a conventional catalyst.

A catalyst can include a phosphorus modified zeolite having partly an ALPO structure. The ALPO structure can be determined by a signal between 35-45 ppm in .sup.27Al MAS NMR spectrum. The zeolite can include at least one ten member ring in the structure thereof. The catalyst can also include a binder and one or more metal oxides. The catalyst can be used in processes in the presence of steam at high temperatures, such as temperatures that are above 300° C. and up to 800° C. The catalyst can be used in alcohol dehydration, olefin cracking, MTO processes, and alkylation of aromatic compounds with olefins and/or alcohols.

A method for producing butadiene from 2,3-butanediol with high selectivity without using a radioactive substance is disclosed. The method for producing butadiene comprises the step of dehydrating 2,3-butanediol in the presence of a catalyst containing an alkali metal salt of phosphoric acid such as an alkali metal dihydrogen phosphate supported on silica. Preferred examples of the alkali metal herein include K, Rb, and Cs. The catalyst is preferably a catalyst prepared by calcination of the silica to which the alkali metal of phosphoric acid is attached.

Described herein are heterogeneous materials comprising a p-type semiconductor comprising two metal oxide compounds of the same metal in two different oxidation states and an n-type semiconductor having a deeper valence band than the p-type semiconductor valence bands, wherein the semiconductor types are in ionic communication with each other. The heterogeneous materials enhance photocatalytic activity.