摘要:
Hydrogen cyanide in hydrogen cyanide containing gas is transformed into ammonia by a special iridium catalyst in the presence of at least the equivalent amount of hydrogen for the change. The ammonia is analyzed to provide a measure of the hydrogen cyanide in the hydrogen cyanide containing gas.
摘要:
The invention relates to coordination compounds of rhodium with silicon-substitued dialkyl or diaryl sulfide groups as ligands in monomeric, polymeric or carrier-fixed forms. The substance can be used as catalysts.
摘要:
4,4'-isopropylidene-bis(2,6-dibromophenol) is produced by reacting 4,4'-isopropylidene diphenol with hydrogen bromide or a mixture of hydrogen bromide with up to an equimolar amount of free bromine in admixture with hydrogen peroxide and in the presence of water and an inert organic liquid.
摘要:
Disclosed is a method for the purification of exhaust air and/or effluents, which may be exhausted, for example, from auto painting units or furniture lacquering units, involving contacting the air and/or effluents with a molded body. The molded body is made from dealuminated zeolite Y and at least one binder, which may be, for example, bentonites, kaolins, sepiolites or attapulgites, and having a hydrophobic factor of from 1.5 to 6.0, wherein a slurry of the binder in water does not exceed a pH of 10 and wherein the molded body is calcined at 850° to 1100° C. The molded body is produced by a process involving mixing pulverulent dealuminated zeolite Y with at least one binder, optionally with the addition of a lubricant and/or a pore former, and optionally with water or an organic solvent, moulding the resulting mass to form a molded body, and drying and calcining the molded bodies.
摘要:
A boron oxide-silicon dioxide mixed oxide which has a BET surface of less than 100 m.sup.2 g, and optionally containing oxides of aluminium, titanium or zirconium, is prepared pyrogenically by flame hydrolysis. The mixed oxide is used in glass making.
摘要:
Molecular sieves are modified by an ion exchange process where metal cations are introduced into the molecular sieves by means of solid state ion exchange. The solid state ion exchange can be carried out as follows: a weighed amount of calcined and activated zeolite is intimately mixed with a precalculated amount of PtCl.sub.2, PdCl.sub.2, RhCl.sub.3, CuCl.sub.2, V.sub.2 O.sub.5 or another compound of the noble metals (e.g., corresponding halides or oxides), the solids mixture is then heated in a current of inert gas (e.g., a current of helium gas or of nitrogen) to temperatures of 400.degree. to 600.degree. C., then cooled down to room temperature and subsequently reduced in a current of hydrogen for 10 to 14 hours at 280.degree. to 350.degree. C. in order to produce small metal clusters from the cationically introduced metal.
摘要:
A process for the production of moulded bodies from dealuminated Y-zeolite (SiO.sub.2 /Al.sub.2 O.sub.3 >20) in which the microporous system of the zeolites and its characteristic adsorption properties are preserved and a binder whose slurry in water does not exceed a pH of 10 used in quantities of from 2 to 40%, based on the quantity of zeolite mass put into the process.
摘要翻译:由脱铝的Y型沸石(SiO 2 / Al 2 O 3> 20)生产模制体的方法,其中保留了沸石的微孔体系及其特征吸附性能,并且其中在水中的浆料不超过10的粘合剂 基于投入该过程的沸石量的2〜40%。
摘要:
The invention relates to a process for preparing a dental material filler in the form of a copolycondensate. An alkoxy silane having a formula of Si(OR.sup.3).sub.4 and a titanium compound are dissolved in a water-miscible solvent. Optionally, additional alkoxysilanes having the formulas R.sup.1 --Si(OR.sup.3).sub.3 and R.sup.2.sub.2 Si(OR.sup.3).sub.2 are also dissolved in the solvent. The reactants are hydrolyzed and condensed to form a reaction mixture from which a heterosiloxane is formed. The heterosiloxane is separated, optionally washed, dried and tempered. The heterosiloxane may then be ground to a desired size and/or formed into various dental materials, such as fillings, inlays, veneers, seals, crowns, bridges, dentures, artificial teeth and adhesives for dental materials. Alternatively, the reaction may take place without the use of a water miscible solvent, such that the precondensing takes place in water.
摘要:
Spherical, polymeric organosiloxane ammonium compounds are disclosed with a silica-like skeleton consisting of: ##STR1## units in which R.sup.1 and R.sup.2 stand for a group ##STR2## in which R.sup.5 is alkylene the oxygen atoms are saturated by silicon atoms of other groups (II) with the optional inclusion of cross-linking agents, R.sup.3 has the meaning of R.sup.1 and R.sup.2 or stands for hydrogen, alkyl, cycloalkyl or benzyl, R.sup.4 is hydrogen or alkyl, cycloalkyl, benzyl, allyl, propargyl, chloroethyl, hydroxyethyl or chloropropyl, X stands for a monovalent to trivalent anion of a protonic acid which forms stable salts with amine bases and x can be a number from 1 to 3.
摘要:
A heat-insulator consisting ofa) A finely distributed, powdery or fibrous substanceb) A microporous casing andc) A gas- and watertight, metal-free casing.The heat insulator is manufactured by optionally the powdery or fibrous substance, optionally bringing it into a microporous casing, optionally pressing it and then optionally drying it. The powdery substance is then brought with the microporous casing into a gas- and watertight, metal-free casing. This gas- and watertight casing is optionally evacuated and sealed.