摘要:
The invention relates to a process for purifying, by treatment with an acid ion exchanger and, if desired, a basic ion exchanger, the methanol employed in the preparation of formaldehyde.
摘要:
The method for preparing carbonyl compounds according to the present invention comprises a vapor phase oxidizing dehydrogenation of C.sub.1 -C.sub.4 alcohols at a temperature ranging from 500.degree. to 700.degree. C. in the presence of a silver catalyst, wherein silver is supported on a carrier having a crystalline structure incorporating alumina and silica in the form of cristobalite.
摘要:
This invention relates to a process for the catalytic conversion of methanol to formaldehyde by oxidation/dehydrogenation over a silver-gold alloy catalyst.
摘要:
An improved process for the manufacture of silver catalysts, in which the silver is applied to conventional dimensionally stable and chemically inert carriers, eg. alumina or quartz moldings, preferably by electroless deposition from silver salt solutions onto a great variety of surfaces acting as carriers, by the use of suitable reducing agents. In a particular embodiment, a uniform deposition of silver and a dense and well-adhering silver layer on the surface of the carrier are achieved by adding certain materials to the silver salt solutions.
摘要:
Formaldehyde is prepared by gas phase reaction of methanol with oxygen in a fluidized bed of an oxide catalyst in which the arrangement of the particles in the fluidized bed provides a negative temperature gradient in the direction of gas flow.
摘要:
A process for the catalytic conversion of methanol to formaldehyde wherein a gas stream containing methanol and oxygen is contacted with a silver catalyst in a first conversion zone containing a silver catalyst to produce an effluent containing formaldehyde, unreacted methanol, and oxidation byproducts; and contacting the first zone effluent with a copper catalyst in a second conversion zone for further conversion of the unreacted methanol. No molecular oxygen is added to the first stage effluent or to the second conversion zone.
摘要:
A process for the preparation of carbonyl compounds by the oxydehydrogenation of (C.sub.1 -C.sub.4)-alcohols is carried out at a temperature from 400.degree. to 700.degree. C. in the presence of a silicate catalyst which has been doped with silver and silver ions. By means of the process carried out at relatively low temperatures, for example, are that high yields are achieved, the content of carbon monoxide is low and the product gas contains, apart from carbon dioxide, no further determinable by-products and has a low water/formaldehyde ratio.
摘要:
Formaldehyde manufacture by oxidative-dehydrogenation of methanol over a silver or copper catalyst. Aqueous formaldehyde solution is obtained from the reaction and is stripped of a mixture of methanol, formaldehyde and water by a low energy process at relatively low temperature and low reflux in a still comprising at least about 1.5 theoretical plates, the stripping conditions being selected to allow substantial reduction of the methanol content of the aqueous formaldehyde solution and recycle of the methanol to the reactor.
摘要:
This invention is concerned with catalysis. More especially, the invention relates to catalytic metal or alloy or both in a form having enhanced catalytic properties, and to the use thereof in catalytic processes. In more detail a catalyst or catalyst substrate according to the invention comprises at least one metal and/or alloy body made by a melt spun or a melt extraction process.
摘要:
A catalyst supporting bed in a vertical reactor for production of formaldehyde by gas phase catalytic dehydrogenation of methanol in the presence of a solid metal catalyst, characterized in that the bed is made of a nickel alloy having a nickel content of not less than 25% by weight at least at the surface.