摘要:
Hollow bodies having a silicon-comprising shell, are produced by, in a gas comprising at least one silane of the general formula SinH2n+2−mXm with n=1 to 4, m=0 to 2n+2 and X=halogen, (a) generating a non-thermal plasma by an AC voltage of frequency f, or operating a light arc, or introducing electromagnetic energy in the infrared region into the gas, giving a resulting phase which (b) is dispersed in a wetting agent and distilled, and then (c) the distillate is contacted at least once with a mixture of at least two of the substances hydrofluoric acid, nitric acid, water, giving a solid residue comprising hollow bodies having a silicon-comprising shell after the conversion reaction of the distillate with the mixture has abated or ended.
摘要:
The present invention relates to a specific process for producing trisilylamine from monochlorosilane and ammonia in the liquid phase. The invention further relates to a plant wherein such a process can be carried out with advantage.
摘要:
The invention relates to a process for preparing trisilylamine and polysilazanes in the liquid phase, in which ammonia dissolved in an inert solvent is initially introduced in a substoichiometric amount relative to monochlorosilane which is likewise present in an inert solvent. The reaction is carried out in a reactor in which trisilylamine formed according to the following equation 4NH3+3H3SiCl→3NH4Cl+(SiH3)3N and polysilazanes are formed. The reactor is subsequently depressurized and TSA is separated off in gaseous form from the product mixture. The TSA obtained is purified by filtration and distillation and obtained in high or very high purity. Further ammonia dissolved in an inert solvent is subsequently introduced into the reactor, using, together with the previously introduced amount of ammonia, a stoichiometric excess of ammonia relative to the amount of MCS previously present. Excess ammonia is subsequently discharged, inert gas is introduced and the bottom product mixture from the reactor is passed through a filter unit, with solid ammonium chloride being separated off and a liquid mixture of polysilazanes and solvent being obtained.
摘要:
The present invention relates to a method of purifying strong acids or strongly acidic media to remove di- and higher valent metal ions, which can be used within the context of the production of high-purity silica. The invention further relates to the use of special ion exchangers for carrying out the method according to the invention and the resultant high-purity silicas.
摘要:
The present invention relates to a process for preparing aqueous colloidal silica sols of high purity from silicate solutions, to aqueous colloidal silica sols with a specific profile of impurities, and to the use thereof. The invention further encompasses high-purity aqueous silica obtained as an intermediate in the course of the purification process, high-purity silicon dioxide obtainable by dewatering, and the use thereof.
摘要:
The present invention relates to a process for producing SiO2 mouldings, comprising the preparation of a free-flowing aqueous SiO2 composition, solidification of the aqueous SiO2 composition and drying of the solidified SiO2 composition, wherein the aqueous SiO2 composition is a self-assembly composition.The present invention further relates to a moulding obtainable by the process according to the invention.
摘要:
The invention relates to a novel method for producing high-purity SiO2 from silicate solutions, a novel high-purity SiO2 with a specific impurity profile and use thereof.
摘要:
A process for preparing epoxysilanes by reacting a hydrogensilane with an allyl glycidyl ether in the presence of a catalyst and working up the crude product obtained, where the catalyst is removed from the crude product and the crude product is subsequently distilled.
摘要:
Particulate magnesium ethoxide having a high coarse particle content can be obtained in a simple and economical manner by the present invention, which provides a process for preparing particulate magnesium ethoxide having a coarse grain content, and includes reacting metallic, optionally activated, magnesium with liquid ethanol under pressure at a temperature above 78° C. The present invention also relates to particulate magnesium ethoxide having a coarse grain content, which contains: 500 &mgr;m.
摘要:
A process for the continuous preparation of 3-halopropylorganosilanes of the general structure RbH3-a-bXaSiCH2CH2CH2Y (III), where: R is CH3, C2H5, C3H7, OCH3, OC2H5 or OC3H7, X is F, Cl, Br or I, Y is F, Cl, Br or I, and a and b are each one of the numbers 0, 1, 2 or 3 and the sum a+b is 1, 2 or 3, comprising reacting, as starting materials, an allyl halide with a silane carrying at least one H atom, wherein the starting materials are present in stoichiometric amounts or one of the starting materials is present in substoichiometric amounts, wherein the reaction carried out is a partial reaction of from 10% to 80%, on a molar basis, of the starting materials, based on either material, when both are present in stoichiometric amounts, or based on the substoichiometric material.
摘要翻译:连续制备通常结构的3-卤代丙基有机硅烷的方法,其中R为CH 3,C 2 H 5,C 3 H 7,OCH 3,OC 2 H 5或OC 3 H 7,X为F,Cl,Br或I,Y为F,Cl,Br或I, 和b分别为数字0,1,2或3中的一个,并且和a + b为1,2或3,包括使烯丙基卤化物与携带至少一个H原子的硅烷作为原料,其中, 原料以化学计量的量存在,或者一种起始原料以亚化学计量的量存在,其中进行的反应是基于摩尔的10%至80%的起始原料的部分反应,基于任一材料 ,当两者都以化学计量的量存在时,或基于亚化学计量的材料。