摘要:
The present disclosure is directed to a method of producing nitric oxide comprising (i) providing a composition comprising a metal-organic framework, and (ii) exposing the composition to a nitric oxide-releasing compound. The disclosure also is directed to compositions, coatings, and medical devices comprising a metal-organic framework.
摘要:
Improved reactors for catalytic, exothermic gas-phase reactions having, viewed in the flow direction of a feed gas, an inlet zone (1), a reaction zone (2) containing at least one catalyst (4), and an outlet zone (3) for the product gas, are described. The reactors are provided in the inlet zone (1) or in the inlet zone (1) and the reaction zone (2) with an insulating liner (6) and/or apparatuses for the transport of cooling media and/or the interior walls of the reactor in the inlet zone (1) or in the inlet zone (1) and the reaction zone (2) consist of inert material. The insulating liner and/or cooling media reduce heat transport from the reaction zone (2) into the inlet zone (1) and thus reduce the risk of preignition of the feed gas mixture used or occurrence of undesirable secondary reactions in the inlet zone (1).
摘要:
A catalyst containment unit, includes two concentric perforate members defining an annular space in which a particulate catalyst may be placed, and process fluid-impermeable end members mounted on the ends of the perforate members, wherein one end member extends across the unit to provide a closed end and the other end member closes the annular space thereby providing an open end through which gases may enter or exit the unit, and suspending means attached to one or both end members for securing the unit within an ammonia oxidation vessel. The unit may be suspended, for example, below a precious metal ammonia oxidation gauze pack and may contain a particulate ammonia oxidation catalyst or nitrous oxide abatement catalyst. A catalyst combination includes a precious metal ammonia oxidation catalyst gauze on a supporting framework and a particulate catalyst disposed in a catalyst containment unit.
摘要:
A catalyst structure suitable for use in an ammonia oxidation process is described including a plurality of shaped catalyst units supported on one or more members in a spaced relationship that allows the structure to flex.
摘要:
A metal fiber based on one or several elements from the group of platinum, palladium, rhodium, ruthenium, and iridium with 0 to 30% by weight of one or several additional alloy elements from the group of nickel, cobalt, gold, rhenium, molybdenum, and tungsten, contains 1 to 500 ppm by weight of boron or phosphorus. A non-woven material or netting, in particular for the production of nitrogen oxide or for the production of hydrocyanic acid, is made of such fibers. For the production of fibers based on noble metals having up to 30% by weight of additional alloy metals by drawing the fibers from a melt, the melting point of the metal is reduced by at least 400° C., before drawing of the fibers, by additionally alloying with boron or phosphorus, and the boron or the phosphorus is removed again from the fibers.
摘要:
Improved reactors for catalytic, exothermic gas-phase reactions, which comprise, viewed in the flow direction of a feed gas, an inlet zone (1), a reaction zone (2) containing at least one catalyst (4) an outlet zone (3) for the product gas, are described. The reactors are provided in the region of the inlet zone (1) or in the region of the inlet zone (1) and the reaction zone (2) with means, for example an insulating liner (6) and/or apparatuses for the transport of cooling media, which reduce heat transport from the reaction zone (2) into the inlet zone (1) and thus reduce the risk of preignition of the feed gas mixture used or occurrence of undesirable secondary reactions in the inlet zone (1) and/or the interior walls of the reactor in the region of the inlet zone (1) or in the region of the inlet zone (1) and the reaction zone (2) consist of inert material.The reactors can be used, in particular, for the oxidation of ammonia, for example in nitric acid plants in which transition metal catalysts configured as honeycombs and having smaller cross sections than the platinum gauzes customarily used are preferably used.
摘要:
A support system for catalyst gauzes in an ammonia oxidation burner and a method of reducing movement of particulate ceramic material due to thermal dilatation includes the catalyst gauzes (1) and possibly support screens (2) being supported by ceramic fillings contained in a burner basket with metal walls and a perforated bottom plate. A “wave breaker” (9, 11) is fixed to the metal wall (4) and/or the outer part/periphery of the bottom plate (5).
摘要:
A fixed bed containing a particulate catalyst or sorbent material (10) subject to operation at high temperature having a shaped boundary member (16) inclined to the direction of fluid flow through the bed that maintains the depth of said catalyst or sorbent at the boundary of the bed through a series of thermal expansion-thermal contraction cycles is described. By maintaining bed depth, the shaped boundary member (16) can prevent bypass of, e.g. ammonia through a bed of particulate ammonia oxidation catalyst.
摘要:
A method and device for removal of N2O in nitric acid production are disclosed. The device is arranged after a heat exchanger, post ammonia burning, before the absorption tower and contains a catalyst, which essentially comprises one or several iron-loaded zeolites.
摘要:
A reactor for the catalytic oxidation of ammonia to form nitrogen oxides which has a noble metal gauze catalyst and a heat exchanger in that order in the direction of flow, a catalyst for the decomposition of N2O is located between the noble metal gauze catalyst and the heat exchanger and in a process for the catalytic decomposition of N2O in a gas mixture obtained in the preparation of nitric acid by catalytic oxidation of ammonia, where the N2O is decomposed catalytically over a catalyst of the decomposition of N2O, the hot gas mixture obtained from the catalytic oxidation of ammonia is brought to contact with the catalyst for the decomposition of N2O prior to subsequent cooling.