DE1143375B - Process for the gentle cleaning of devices and devices or device and device parts contaminated with polyamide melt - Google Patents

Description

Process for the gentle cleaning of those contaminated with polyamide melt Devices and apparatus or parts of devices and apparatus Addition to patent 1,133,212 The subject of patent 1133 212 is a method for the gentle cleaning of Equipment and apparatus, especially metallic ones, contaminated with polyamide melt or parts of equipment and apparatus, after which the items to be cleaned in a pressure-resistant, closed container together with glycol to temperatures above 220 ° C, preferably above 2500 C, heated and rinsed with water after cooling.

For example, spinnerets, spinning pumps, reaction vessels, Autoclaves, spinning grates, measuring devices, measuring bodies, etc.

In a further development of the process it was found that the process according to the main patent is not limited to the use of glycol, but generally monohydric or polyhydric alcohols at temperatures above 220 ° C., preferably at 250 to 300 ° C, and under the vapor pressure corresponding to the respective temperature or with a correspondingly high boiling point of the alcohol under normal pressure come.

Basically there are both primary and secondary or tertiary monohydric or polyhydric alcohols, pure or mixed with water or mixtures with one another into consideration, e.g. B. methanol, ethanol, propanols, butanols, etc., propanediols, butanediols, Pentanediols, hexanediols, pinacols, etc., glycerine and its derivatives, erythrites, Pentites, hexites, etc., cyclic alcohols such as mono- and polyoxyclohexanes, etc., as well as Carbon derivatives of the aforementioned compounds with alkyl, aryl, halogen, amine, Mercapto, oxo, alkoxy, aryloxy and carboxyl groups, aromatic alcohols, such as Phenols, cresols and their derivatives, etc., mixed aromatic-aliphatic alcohols etc., low boiling point alcohols are necessary in terms of when Temperatures resulting vapor pressures of less practical importance.

The duration of the cleaning treatment depends on the one hand Degree of soiling as well as how easy the soiled parts are for the Alcohol are accessible, on the other hand, according to the level of the temperature used. While at temperatures below 3000 C a treatment depending on the degree of soiling and complexity of the parts to be cleaned takes 1 to 4 hours when applied of temperatures above 3000 C the duration of the treatment significantly, for example about 20 minutes can be shortened, yes, at these temperatures it is only enough a simple heating up and immediate shutdown to get cleaned properly Apparatus parts to arrive.

By adding suitable catalysts, e.g. B.

Mineral acids, ammonium chloride, etc., in small amounts, can result the process according to the invention, in particular, of the acceleration of the reaction triggered thereby can be varied with regard to treatment duration and possibly temperature level.

For economic reasons, it is primarily used as a washing-up liquid Water in question. It can also be mixed with dilute mineral acid and then water or rinsed with an alcohol.

Example 1 The parts to be cleaned are placed in an autoclave. The autoclave is filled with propanol so that the material to be treated is covered. To after closing the autoclave, it is heated to 220 to 230 ° C (pressure about 25 to 33 atü) heated.

After cooling, it is opened and the material to be treated is removed, washed with water and dried.

Example 2 The material to be treated is treated with 1,4-butanediol (bp.

2300 C) in the autoclave for 1 to 2 hours at 2500 C (pressure approx. 1 to 2 atü) heated. After the autoclave has cooled down and opened, the goods are removed, with Washed with water and dried.

Example 3 The material to be treated is stored in the autoclave for 1 to 2 hours Phenylethyl alcohol (bp. 220 ° C / 750 mm Hg) heated to 2700 C (pressure about 2 to 3 atmospheres), then washed with water and dried.

Example ~ 4 The material to be treated is placed in a reaction vessel which is equipped with is provided with a reflux condenser, poured glycerol over it. It is heated to the boil (Bp of the glycerol = 290 ° C) and refluxed for 1 to 2 hours. After this When the solution cools, the material to be treated is removed and possibly diluted with it Sulfuric acid and water washed and dried.

With the help of the method according to the invention, the Parts recovered clean and bright without corrosion or scaling can. The procedure is for cleaning all types of polyamide stained Devices and device parts suitable, even if the dirt has decomposed or cracked products. When cleaning Spinnerets will produce a perfect result with, for example, spinnerets achieved fine slot-shaped nozzle openings. The corresponding Alcohol is after multiple uses (five to ten times) recovered by distillation and is then ready for use again.

Claims (2)

PATENTAN'S CLAIMS: 1. Process for the gentle cleaning of with polyamide melt contaminated, in particular metallic devices and apparatus or equipment and Apparatus parts in which the items to be cleaned are stored in a pressure-tight, closed container heated together with glycol to temperatures above 2200 C, preferably above 2500 C. and rinsed with water after cooling, according to patent 1133 212, characterized in that that instead of glycol other mono- or polyhydric alcohols are used or in The items to be cleaned have a correspondingly high boiling point of the alcohol (at least 290 ° C) with the alcohol in an open container, possibly under reflux cooling, is treated. 2. The method according to claim 1, characterized in that the items to be cleaned after cooling with a diluted mineral acid and then with water rinsing with alcohol. ~~~~~~~ Publications considered: German U.S. Patent No. 910,593.