摘要:
The present invention relates to a process for tanning animal hides which comprises the steps of: bating and pickling the animal hide in aqueous solution, reducing the liquid content of the animal hide, replacing at least some of the liquid removed from the animal hide in the preceding step by a tanning solution which contains the tanning agent to be imbibed by the animal hide in an amount not exceeding an excess of 80%, and treating the animal hide containing the tanning solution with compressed gas in a pressurized container for a period of at least 15 minutes. Such a process is substantially wastewaterless, optionally even completely wastewaterless, and delivers high-quality through-tanned leathers or furs after short treatment times.
摘要:
The present invention relates to a process for tanning animal hides which comprises the steps of: bating and pickling the animal hide in aqueous solution, reducing the liquid content of the animal hide, replacing at least some of the liquid removed from the animal hide in the preceding step by a tanning solution which contains the tanning agent to be imbibed by the animal hide in an amount not exceeding an excess of 80%, and treating the animal hide containing the tanning solution with compressed gas in a pressurized container for a period of at least 15 minutes. Such a process is substantially wastewaterless, optionally even completely wastewaterless, and delivers high-quality through-tanned leathers or furs after short treatment times.
摘要:
A method for removing free fatty acids from fats or oils of biological origin or their steam distillates by extracting the free fatty acids with a mixture of basic organic nitrogen compounds and water as an extraction medium at a temperature below the boiling point of the organic nitrogen compounds. The content of the basic organic nitrogen compounds in the extraction medium is 20-30% by weight. In this manner, the formation of a viscous soapstock which is difficult to remove is prevented. The boiling point of the basic organic nitrogen compounds used is the same as or above boiling point of water and below the boiling point of the fatty acids to be extracted in order to enable simple recovery of the extraction medium.
摘要:
The invention concerns a method for producing fatty acid esters from fatty acid triglyceride and in particular from animal or vegetable fats and oils by transesterification with a monovalent low-molecular weight alcohol in the presence of a homogeneous or heterogeneous catalyst. In accordance with the invention, the formed fatty acid ester is extracted from the reaction mixture by means of a near-critical extractant. In this way fatty acid esters are obtained at high yield and excellent purity. As the extractant preferably a low pressure gas having a reduced temperature at 20° C. of about 0.7, preferably of equal to or greater than 0.7, is employed. Preferred extractants are carbon dioxide, propane, butane, dimethyl ether, ethyl acetate or mixtures thereof.
摘要:
In order to make processes for finishing animal hides or pelts less labor-intensive and more environmentally compatible, a process is proposed in which, following a conventionally conducted soak, the animal hides or pelts are treated with a conventional tanning solution in which carbon dioxide has been dissolved under pressure. This makes it possible to reduce considerably the period of time usually required for the production of leather or pelts, since the treatment period is reduced markedly. Furthermore, it is possible in this way to combine conventional treatment steps and to conduct them in only one single treatment step. Instead of the 20 to 40 t of waste water per tonne of leather or pelt which are customary with conventional processes, only about 2 t of waste water per tonne of leather or pelt are now produced. Besides having a sharply reduced environmental impact, the proposed process is also significantly more economical than conventional processes, owing to the considerably shorter overall processing time.
摘要:
The present invention relates to a method for producing fatty acid esters from fats and/or oils of biogenic origin by transesterification with monovalent or polyvalent alcohols in the presence of a special hydroxy-functional quaternary ammonium compound as the catalyst.
摘要:
The present invention relates to a method for producing fatty acid esters from fats and/or oils of biogenic origin by transesterification with monovalent or polyvalent alcohols in the presence of a special hydroxy-functional quaternary ammonium compound as the catalyst.
摘要:
The invention relates to a process for the preparation of fatty acid esters from fats and oils of biological origin by transesterification with monohydric alcohols in the presence of basic catalysts, the catalysts being salts of a basic organic compound and carbonic acid.
摘要:
The invention relates to a process for the preparation of fatty acid esters from fats and oils of biological origin by transesterification with monohydric alcohols in the presence of basic catalysts, the catalysts being salts of a basic organic compound and carbonic acid.
摘要:
In a process for producing a pulverulent product from a liquid substance or mixture of substances, the liquid substance or mixture of substances to be pulverized is first provided in a pressure vessel. A gas is then dissolved under elevated pressure in the liquid substance or mixture of substances. The resulting liquid/gas solution is then conducted out of the pressure vessel and to an expansion element, through which it is passed and rapidly expanded. Upstream of the expansion element, in the expansion element or downstream, in particular just downstream, of the expansion element, a solid pulverulent auxiliary is admixed. In this manner, a stable pulverulent product results from the solution or from the substance or mixture of substances.