The oxidation of toluene on various molybdenum-containing catalysts

The activities for the vapour-phase oxidation of toluene of various molybdenum-containing catalysts have been measured in a flow microreactor operating at 1 atm pressure. The catalysts comprised (a) unsupported crystalline MoO3, (b) Mo oxide monolayers on Al2O3, CeO2, TiO2, and ZrO2 supports, and (c) Al-, Ce-, and Zr-molybdate salts. The rates of oxidation of toluene per unit surface area on the monolayer catalysts are higher than those on the corresponding salts, but the selectivities for the partial oxidation products show the opposite trend. The catalytic behaviour of unsupported MoO3 resembles more closely that of the salts than that of the monolayer catalysts. The kinetic data for the oxidation of toluene on all catalysts can be interpreted on the basis of a reduction-oxidation mechanism. The energies of activation for the reduction and oxidation steps are correlated with the ionic potentials of the cations in the supports. Poisoning by pyridine of MoOx/TiO2 has a profound effect on the activity and selectivity of the monolayer catalyst and gives some information about the nature and concentration of the active sites

Investigation of the surface structure and activity of molybdenum oxide-containing catalysts : I. An infrared study of the surface structure of molybdena-alumina catalysts

A comparison has been made of the infrared spectra of alumina with molybdenum oxide-alumina in both the oxidized and reduced forms. In the case of molybdena-alumina prepared via adsorption of gaseous MoO2(OH)2, the spectra show that a practically complete monolayer of Mo6+ oxide covers the alumina. After reduction with hydrogen the hydroxyls of the carrier appear. From the reversibility of reduction and oxidation under mild conditions it has been established that the reduced oxide is present as an interrupted monolayer

Reduced molybdenum oxide catalysts with high surface areas. Preparation and activites

From solutions of ammonium molybdate this salt was precipitated with acetone. Decomposition in air at 330 °C yields MoO3 with a specific surface area of 17 m2/g, by means of reduction with hydrogen 4.5, 4 and 3.5 valent oxides may be formed with 30, 50 and 80 m2/g, respectively. Molybdenum (VI) oxide present as a monomolecular layer on supports is much less readily reduced than unsupported MoO3. This difference reflects the interaction of Mo ions with ions of the support. The reducibilities of the various catalysts show that Mo(VI) oxides interact far less with SiO2 than with Al2O3, CeO2 and ZrO2. This is also reflected in the rates of 2-propanol decomposition on these catalysts, the activities on MoOx and on MoOx−SiO2 being much higher than on the other catalysts

Ink composition containing a particular type of dye, and corresponding ink jet printing process

An ink composition is disclosed which contains a novel type of dye (DYE)n(SAU)m that is capable of self-assembling under appropriate conditions, or is capable of assembling with another analogous dye (DYE')n'(SAU')m', or is capable of assembling with a compound (SAU'')p(X)q, thus forming supramolecular structures. Also disclosed is an ink jet printing process using these novel dyes, and an ink jet printing apparatus provided with an ink cartridge containing such a dye

Прибыльность предприятия и резервы ее повышения

Целью данной работы является анализ факторов, влияющих на прибыль, анализ показателей оценки прибыли, и разработка рекомендаций по увеличению прибыли