Future trends in the refining catalyst market

The oil refining industry operation is analyzed in order to estimate the future catalyst market trends. The refining catalyst market corresponding to the main catalytic processes is estimated taking into account the following information: (i) the average refining capacity increases for the main catalytic processes since 1999, (ii) the additional refining capacity due to future plans of construction and expansion of refineries and process units that will be added by 2005, and (iii) the past refining catalyst market behavior. From this information, we have determined for the main catalytic processes a global average factor, expressed as processed oil barrels per dollar of catalyst. According to our estimates, the global refining catalyst market will increase from $2.32 billion in 2001 to about$2.65 billion in 2005 (3.6% annual growth). Hydrotreating, fluid catalytic cracking, hydrocracking and isomerization represent about 74% of the total catalyst market and will grow by about $34,$32, $11 and$2.5 million per year, respectively. However, naphtha reforming catalyst market will not grow during 2001-2005. Higher catalyst spending growth is expected for the North America region ($27.5 million per year). (C) 2003 Elsevier B.V. All rights reserved

Vanadium aluminium oxynitride catalysts for propane ammoxidation reaction - Effect of the V/Al ratio on the structure and catalytic behviour

The influence of the V/AI ratio composition on the physico-chemical and catalytic properties of the vanadium aluminium oxynitride system was investigated. The samples were prepared by co-precipitation of vanadium and aluminium solutions containing different metal compositions (0.1-0.9 V/Al) at pH 5.5 and characterized by XRD, XPS, Raman and BET surface area. Catalytic activity measurements for the propane ammoxidation reaction were carried out under optimal acrylonitrile selectivity conditions. X-ray diffraction pattern indicated that all the catalysts in both oxide precursor and nitride state show amorphous character. BET surface area was higher for the sample with V/Al ratio of 0.25, before and after nitridation treatment. This sample showed optimal catalytic performances, with 50% acrylonitrile selectivity and 60% propane conversion. The optimal nitridation degree, which induces an optimal reduction degree of vanadium, would explain the maximal catalytic activity observed for the sample prepared using the V/Al ratio composition of 0.25. (c) 2005 Elsevier B.V. All rights reserved

Influence of the reaction conditions on the activity properties of vanadium-aluminium oxynitride propane ammoxidation catalyst

The influence of different reaction conditions on the catalytic activity of vanadium-aluminium oxynitride "VAlON" in propane ammoxidation is investigated. This new catalytic material exhibits amorphous character, high specific surface area, basic-redox properties and remarkable acrylonitrile production per hour and amount of catalyst. Optimal performance is achieved when the reaction temperature is 500 degreesC and the molar ratio of propane, oxygen, and ammonia in the gas feed is 1.25:3: 1. Under these optimal reaction conditions, the catalyst showed a propane conversion level of 60%, an acrylonitrile selectivity of 56%, and an acrylonitrile productivity of 8121/kg h. The formation of a propylene intermediate compound as well as hydrogen cyanide was detected only for those reaction conditions where the NH3:C3H8 ratio was lower than 1. This suggests differences in the reaction mechanism with respect to conventional V-Me-oxide propane ammoxidation catalysts. In propane ammoxidation over VAlON catalysts, ammonia seems to play a double role: (i) as a reagent necessary for the thermal nitridation and generation of nitrogen species, (ii) participating in N-insertion step for the acrylonitrile formation from propane. The catalytic performances depend on the generation of nitrogen species as a function of the reaction conditions, which determine the level of propane conversion and selectivity to the reaction products. (C) 2003 Elsevier B.V. All rights reserved

Oxidative dehydrogenation of propane over (Mo)-Sm-V-O catalytic system. Role of the different phases

The (Mo)-Sm-V-O catalytic system has been exhaustively studied in the propane oxidative dehydrogenation reaction. In order to obtain different surface arrangements, simple oxides (V2O5, SM2O3 and MoO3), SMV mixed oxides with different Sm/V molar ratio and SMVO4 impregnated with vanadium, samarium or molybdenum were prepared. The function that the possible arrangements play has been identified. A slight samarium excess favors total combustion causing a strong drop of selectivity, therefore, it is necessary to avoid it. On the other hand, vanadium excess constituting surface vanadium oxide species (VOx) notably increases the catalytic activity while a higher vanadium amount leads to crystalline V2O5 formation and the catalyst behavior tends to that of bulk V2O5, Molybdenum at low concentrations constitutes surface molybdenum oxide species (MoO.) which showed to be highly selective in propane ODH. High contents of molybdenum favor the formation of crystalline MoO3, thus, causing an important catalyst deactivation. Finally, a comparison with other known efficient vanadium based catalysts is made and hence, the potentiality of (Mo)-Sm-V-O catalysts is shown