Hydrothermal synthesis reactor cleaning
The hydrothermal synthesis reactor is a closed vessel capable of decomposing poorly soluble substances. High-pressure digestion tanks, hydrothermal synthesis tanks, generally have volumes ranging from tens of ML to several hundred ML. It can be manually screwed and sturdy. The applicable temperature is 180 °C; the temperature can reach 230 °C. The more common liner materials are PTFE liner and stainless steel and PPL aligning polystyrene. After the synthesis of the hydrothermal reactor, the problem of headache is that the reaction product is attached to the wall of the biliary body. How to wash the hydrothermal reaction kettle, sometimes using concentrated nitric acid for a long time does not help. This will definitely bring a lot of trouble to the next set of experiments. We have summarized the issue of customer feedback, and now we share it and hope to help you:
First, the newly purchased hydrothermal reaction tank cleaning
When the newly purchased hydrothermal reactor is first cleaned, add some alkali or boil to the inner tank for a while. When using a hydrothermal reaction kettle, do not heat it quickly. Slowly, the temperature should not be too high (such as 200 degrees Celsius), otherwise the PTFE liner will be easily deformed. Start at 150 degrees Celsius for a few hours, then at 200 degrees Celsius for a few more hours, then remove the natural cooling. Then, when the experimental temperature is 200 degrees Celsius, the inner tank of the hydrothermal reactor does not deform.
Second, the hydrothermal reactor has different reaction media and different cleaning methods.
The catalyst of the hydrothermal reaction kettle is different, and the cleaning method is also different. If the silicon system is used, it can be heated with a little hydrofluoric acid or alkali to wash it. After the use of the silicon metal system, it depends on what acid it dissolves, and the hydrochloric acid needs to be used. Wang Shui: three to one ratio of concentrated nitric acid and concentrated hydrochloric acid).
For example: use potassium permanganate dissolved in water, then add 3-5mL of concentrated hydrochloric acid, put it in the reaction kettle and seal it, 180 degree hydrothermal reaction for 5-10 hours, very clean.
Third, the laboratory commonly used hydrothermal reactor cleaning method
Wang Shui: a ratio of concentrated nitric acid to concentrated hydrochloric acid of three to one, washed with aqua regia.
Fourth, other hydrothermal reactor cleaning methods
1. After the end of the experimental reaction, add about 1:5 mixed solution of nitric acid and water in the hydrothermal reaction kettle, and then heat to 180 ° C for about 12 hours. These data are not fixed and need to be reacted according to your experiment. As the case may be, the ratio of the mixed solution is not necessarily 1:5, and the temperature is not necessarily up to 180. Here is just a small series to give you a reference data. However, this method has a drawback in that the repeatability of the experiment is deteriorated.
2, boiled with oxalic acid solution for 6 hours, the temperature of about 160 degrees depends on the experimental situation.
3. Use hydrofluoric acid or ethanol to heat the reaction, or other strong acid!
In addition, the hydrothermal reactor is strictly prohibited to use a low boiling point system and is easy to explode. When the reactor is used up, the liner and the jacket are separated and dried at 50 °C.
Shine Skin Pumpkin Seeds,Shine Skin Pumpkin Seeds Does,Shine Skin Pumpkin Seeds Extract,Shine Skin Pumpkin Seeds Edible
Wuyuan county dafeng oil food co.,ltd , https://www.dafengfood.com.cn