摘要:
A process for purifying creatine is described in which the creatine to be purified in the form free of water of crystallization is introduced into a saturated aqueous solution of creatine monohydrate, in which the creatine free of water of crystallization is dissolved with hydration, crystals of creatine monohydrate precipitate from the aqueous solution and these are separated off from the aqueous solution.
摘要:
The present invention relates to an improved process for preparing pure riboflavin (vitamin B2) of the B/C modification in granule form. Furthermore, the invention relates to pure riboflavin in granule form which has a bulk density to be determined in accordance with DIN 53468 of from 0.45 to 0.7 g/ml and, after tableting, has a dissolution of at least 80%.
摘要:
Ethers, esters or acid anhydrides are advantageously obtained when a cake of a first reactant selected from salts of organic or oxygen-containing inorganic acids or alkoxides disposed on a filter element is flowed through by a solution of a second reactant selected from inorganic or organic acid halides and alkyl halides, so that the insoluble halide salt formed remains on the filter element. The halide salt can thus be removed substantially quantitatively in a simple manner.
摘要:
The present invention relates to a process for the formation of profen crystals, which comprises carrying out the formation of solids by displacement precipitation, cooling crystallization, evaporative crystallization or a combination thereof in the presence of one or more additives, and the use of the profens thus prepared for pharmaceutical formulations.
摘要:
A process for the isolation of 3-[2-chloro-4-(trifluoromethyl)phenoxy]benzoic acid of the formula I ##STR1## from an aqueous solution of its metal salt comprises a) reacting the metal salt of 3-[2-chloro-4-(trifluoromethyl)phenoxy]benzoic acid with an organic or inorganic acid;b) heating the reaction mixture until a liquid two-phase system of organic and aqueous phase has formed; andc) separating the organic phase from the aqueous phase.
摘要:
A method for folding an airbag for an airbag module in which the airbag is disposed on a support is provided. At least one piling element for folding the airbag is provided next to the exterior edge of the airbag disposed on the support. The airbag is folded together using the at least one piling element in that the piling element is moved along the support in the direction toward the interior of the airbag disposed on the support. A retainer protrudes from the at least one piling element and moving together with the piling element during the movement thereof and reaching over or under an edge area of the airbag. The at least one retainer acts on an edge area of the airbag in such a way that an undercut is formed in the airbag through the effect of the retainer.
摘要:
An airbag arrangement for a vehicle occupant restraint system includes an inflatable airbag having at least one outflow opening through which gas can flow out of the airbag. The airbag arrangement also includes a stretchable element including a covering structure for adjustably covering a portion of the outflow opening. The covering structure moves relative to the outflow opening when the stretchable element is stretched. The airbag arrangement also includes a fastener for fastening the stretchable element to the airbag so the stretchable element stretches when the airbag inflates and the covering structure moves relative to the outflow opening changing the size of the covered portion of the outflow opening.
摘要:
A process is described for preparing ammonium salts of aromatic carboxylic acids by reacting an aromatic carboxylic acid with ammonia in an aprotic solvent, which comprises carrying out the reaction in a closed vessel by continuously introducing a solution of the aromatic carboxylic acid in the aprotic solvent and passing in gaseous ammonia so that an ammonia partial pressure in the range from 0.1 to 3 bar is maintained in the gas space of the vessel, and discharging a suspension of the ammonium salt in the aprotic solvent. The process allows the preparation of ammonium salts of defined crystal size having a narrow size distribution.
摘要:
A process for preparing polyether polyols includes a precipitation step, a recrystallization step, and a reaction step. In the precipitation step, a multimetal cyanide compound is precipitated by reaction of a metal salt with a cyanometalate compound. In the recrystallization step, the multimetal cyanide compound precipitated above is recrystallized by adding further metal salt and/or further cyanometalate compound. The recrystallization forms a multimetal cyanide catalyst compound. In the reaction step, an initiator and one or more alkylene oxide are reacted in the presence of the multimetal cyanide catalyst compound.
摘要:
The continuous production of acetylene diurea takes place by means of the reaction of glyoxal with urea in the presence of mineral acids. The reaction is carried out in at least one reactor having a mixing device, into which glyoxal, urea, and mineral acid are continuously fed, and from which a suspension of acetylene diurea in mother liquor is discharged. The acetylene diurea is mechanically removed from the mother liquor, and the remaining mother liquor is recycled back into the reactor, in whole or in part.