How to conduct a pilot test for waste solvent recovery? What’s the process?

It is recommended that the original poster change the title of the main post; it’s too short and does not clearly convey the topic.

Distillation is generally used to purify organic solvents. However, I suggest that you should first conduct pilot tests before moving on to pilot-scale trials.

First, choose a viable method in the laboratory to give it a try; if it works, then scale it up

First, filter out solid or suspended impurities, then carry out distillation on a pilot scale. Check the color of the material after distillation; if it does not meet the required standards, decolorization must be performed before distillation

I’m not in the chemical industry. . Originally, this post was meant to be posted in the Analysis section; they said it was accidentally posted in the wrong place and have moved it to the Fine Chemicals section. Recycling other people’s waste solvents was our boss’s idea; the intention was to take the waste solvents that would otherwise be sent to incinerators after production at other factories and process them again. This seems to be beneficial for the environment, right? I don’t understand it because I’ve never done pilot tests. Please forgive me all.

First, it is necessary to find out from the manufacturer what the main ingredients are What solvents might be contained in it. Only by knowing the components can it be processed. Second: it is necessary to understand the properties of the required raw materials, such as their water solubility, etc. Properties of the main raw materials: insoluble in water, soluble in water. Pre-treatment: washing with water, dehydration using appropriate dehydrating agents. Distillation: pilot-scale distillation for analyzing different components. Is color removal necessary? Color removal is carried out according to requirements. Is it likely to form peroxides? A reducing agent is added. Is oxygen-free conditions required?

Waste solvents give me the impression that anything is possible. It is recommended that the original poster request a quality report from the manufacturer at the time of purchase; incidentally, the report provided by the seller may not accurately reflect the composition of the solvent you have purchased. It is best to conduct your own analysis after making the purchase, and then choose a suitable pilot-scale method based on the results of that analysis. Once the pilot-scale approach has been determined, consider moving on to pilot production.

Only by understanding the basic properties and composition of this waste liquid can a reasonable recycling method be provided.

Mainly, what substances do you want to extract from it? At the very least, it’s necessary to test what substances are present in the waste liquid; it’s also important to know what substances other manufacturers use and which ones need to be removed, so as to obtain a solvent of high purity. I don’t know anything; how are you going to do it?

Safety must be taken into account when recovering solvents; most solvents are volatile and flammable, and some are toxic – safety comes first

I. The composition of solvents can be analyzed using methods such as GC-MS; if there is a sufficient boiling point difference between the target solvent and other components, purification can be achieved through distillation. Some components that cannot be removed by distillation can be eliminated through chemical methods; for example, small amounts of alcohol in furan can be removed using Grignard reagents, and if organic acids are present in the solvent, it can be washed with an alkaline solution. II. To remove colors and odors from the solvent, it is best to know the origin of the solvent, what type of solvent it is, and which raw materials or products may produce colors and odors during the reaction process. Generally, distillation or short evaporation can remove color, and adsorption using activated carbon and similar materials can also be employed. III. If it is a solvent that is miscible with water, it is generally quite difficult to remove the water content. Our factory has used molecular sieve to dry solvents, and the molecular sieve can be reused ； Moisture can also be removed by adding some inexpensive desiccants ； Industrially, water can also be removed by adding appropriate solvents and using azeotropic distillation.

Could you be more specific, such as the main components and the properties of the raw materials?