428results about How to "Long catalyst life" patented technology

An oxide catalyst composition for use in producing methacrolein or a mixture of methacrolein and methacrylic acid, wherein the oxide catalyst composition is represented by the formula (Mo+W)l2BiaAbBcFedXeSbfOg, wherein: A is at least one member selected from the group consisting of Y and the elements of the lanthanoid series exclusive of Pm; B is at least one member selected from the group consisting of K, Rb and Cs; X is Co solely, or a mixture of Co and at least one member selected from the group consisting of Mg and Ni; and a, b, c, d, e, f and g are, respectively, the atomic ratios of Bi, A, B, Fe, X, Sb and O, relative to twelve atoms of the total of Mo and W, wherein the atomic ratios (a to f) of the elements and the relationship between the amounts of the elements are chosen so as to satisfy specific requirements.

The activity of a dehydrogenation catalyst is improved by increasing the water concentration maintained in the reactants toward the start of the catalyst's life, but after the catalyst has deactivated to the extent that the temperature required to maintain the conversion per pass of paraffinic hydrocarbon through the reaction zone increases by at least 2° C.

An oxygenate conversion catalyst useful in the conversion of oxygenates such as methanol to olefinic products may be improved by the use of a catalyst combination based on a molecular sieve in combination with a co-catalyst comprising a mixed metal oxide composition which has oxidation / reduction functionality under the conditions of the conversion. This metal oxide co-catalyst component will comprise a mixed oxide of one or more, preferably at least two, transition metals, usually of Series 4, 5 or 6 of the Periodic Table, with the metals of Series 4 being preferred, as an essential component of the mixed oxide composition. The preferred transition metals are those of Groups 5, especially titanium and vanadium, Group 6, especially chromium or molybdenum, Group 7, especially manganese and Group 8, especially cobalt or nickel. Other metal oxides may also be present. The preferred molecular sieve components in these catalysts are the high silica zeolites and the SAPOs, especially the small pore SAPOs (8-membered rings), such as SAPO-34. These catalyst combinations exhibit reduced coke selectivity have the potential of achieving extended catalyst life. In addition, these catalysts have the capability of selectively converting the hydrogen produced during the conversion to liquid products, mainly water, reducing the demand on reactor volume and product handling.

A homogenous process for the hydrogenation of the carboxylic acids and / or derivatives thereof in the presence of a catalyst comprising ruthenium, rhodium, iron, osmium or palladium, and an organic phosphine is described in which the hydrogenation is carried out in the presence of at least about 1% by weight water. A process for regenerating a catalyst comprising ruthenium, rhodium, iron, osmium or palladium and an organic phosphine is also described in which the regeneration is carried out in the presence of hydrogen and water.

A multitube reactor, wherein tubes having smaller tolerance between a nominal size and actual sizes are used as reaction tubes to stably perform a high yield reaction for a long period, a catalyst is filled into the reaction tubes so that the catalyst layer peak temperature portions of the reaction tubes are not overlapped with the connection sites thereof with baffles to effectively prevent hot spots from occurring and stably perform a reaction for a long period without the clogging of the reaction tubes, a heat medium and raw material gas are allowed to flow in the direction of a countercurrent and a specified type of catalyst is filled into the reaction tubes so that activity is increased from the inlet of the raw material gas to the outlet thereof to prevent the autooxidation of products so as to prevent equipment from being damaged due to the reaction, and, at the time of starting, gas with a temperature of 100 to 400° C. is led to the outside of the reaction tubes to increase the temperature of the reaction tubes and, a heat medium, which is solid at the room temperature, is heated to circulate to the outside of the reaction tubes to efficiently start up the reactor without affecting the activity of the catalyst.

A heavy lubricant base stock is made by (a) producing a synthesis gas from natural gas, (b) reacting the H2 and CO in the gas in the presence of a cobalt Fischer-Tropsch catalyst, at reaction conditions effective to synthesize waxy hydrocarbons boiling in the heavy lubricant oil range, which are hydrodewaxed it at least two stages, with interstage separation and removal of the lighter material.