Selection of refrigerant for the condenser

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A certain sodium alcohol is required as a catalyst in the company’s production process. Due to the high level of free base in the commercially purchased sodium alcohol, its catalytic activity is not very satisfactory. Therefore, the company has been using the sodium metal method to prepare it on its own. But recently, there was a leak in our condenser, and the condensate entered the sodium alcohol preparation tank. This causes the reaction inside the kettle to accelerate rapidly, and the flow rate of the solvent (alcohol) back increases quickly. Fortunately, it was dealt with in a timely manner, and no major accident occurred. In response to this, the company held a special meeting to discuss the issue and reached the following decisions: 1. Actively seek other refrigerants to replace the circulating condensate water. Then, the compressor is used to transfer heat by circulating this refrigerant ； 2. Before finding a suitable refrigerant, and before each batch of material is added, the condenser must be pressurized to check for leaks. As for what type of refrigerant to use, we discussed it internally as well and gathered some information. But none of them seem quite right. a. Ethylene glycol: Ethylene glycol has low volatility and is often used as a refrigerant. However, the reaction between ethylene glycol and sodium metal is still quite vigorous ； b. Light thermal oil: Light thermal oil has a low specific heat capacity, making it suitable for cooling substances at temperatures of 300–500°C; however, its cooling effect is poor when used to cool substances at temperatures below 100°C ； c. High-boiling-point solvent oils: Alkanes do not react with sodium metal, but those with short carbon chains are volatile and classified as flammable liquids. Will those with longer carbon chains decompose under prolonged high temperatures? Moreover, its specific heat is not high either; it is likely that cooling substances to below 100°C will not yield very good results ； d. Esters, ethers: Sodium metal does not react with esters or ethers, but if no suitable product is available at the moment, there is generally an issue of flammable liquids having volatility ； e. Alcohols: Butanol, pentanol, and hexanol were also considered; alcohols have a higher specific heat capacity. Moreover, even in terms of nature, if it leaks into our sodium alkoxide preparation tank, it’s not a major problem; yet there is still the issue of the volatility of flammable liquids ； f. Low-temperature heat transfer oil – this is something that interests me quite a bit. I’m just not sure whether low-temperature heat transfer oil and light heat transfer oil are the same thing