Acetone is the simplest ketone in the saturated fatty ketone series and exists in nature in its free state, mainly in essential oils in the plant world, such as tea oil, pine resin essential oil, citrus essential oil, etc.

The industrial production of acetone in the world is currently dominated by the isopropylbenzene method. While a large amount of industrial production and manufacturing of acetone wastewater makes great concern to the high disposal cost and environmental hazards, through the process of heating distillation, membrane filtration, fermentation method, isopropyl benzene oxidation synthesis method and other separation methods, pure acetone can be recovered and purified for reusing.

The acetone recovery and purification process not only save a lot of procurement costs, but also reduce the pollution of the environment.

As a process equipment supplier on solvent recovery, I truely understand the importance of recovering and purifying acetone. In this post, I will list the main equipment and illustrate how to effectively recover acetone by advanced process technologies.

Why To Recover Acetone?

Acetone is a widely used solvent in various industrial production. It has many benefits, including its ability to dissolve many substances, evaporate quickly, and its low toxicity.

However, it can be expensive, and improper disposal can be harmful to the environment.

Effective and high efficient acetone recovery and purification can help save costs and reduce environmental impact.

• Acetone is a good solvent, used in paints, binders, cylinders acetylene, etc. Also used as diluent, cleaning agent, extractant.
• Used as an extracting agent in the oil and grease industry.
• Used in the production of organic glass monomer, bisphenol A, diacetone alcohol, ethylene glycol, methyl isobutyl ketone, methyl isobutyl ketone, methyl isobutyl methanol, phorone, isophorone, chloroform, iodoform and other important organic chemical raw materials.

Industries To Which Acetone Recycling Applies:

The harmful effects of acetone：

• Health hazards: The symptoms of acute poisoning are mainly paralysis of the central nervous system, weakness, nausea, headache, dizziness, and agitation. In severe cases, vomiting, shortness of breath, cramps, and even coma occur. Irritating to eyes, nose and throat. After oral ingestion, there is a burning sensation in the lips and throat, followed by dry mouth, vomiting, coma, acidosis and ketosis.
• Chronic effects: dizziness, burning sensation, pharyngitis, bronchitis, weakness, agitation, etc., after prolonged exposure to the product. Long-term repeated skin exposure can cause dermatitis.
• Explosion hazard: The product is extremely flammable and irritating.

So it is significant to design proper process and equipment for acetone recover and purification, and reduce safety hazards associated with the accumulation of waste solvents.

Factors to Consider Before Acetone Recovery

Before starting the acetone recovery and purification process, it is essential to consider the following factors:

• Feed Quality and Outlet Purity Level Required

The feed stream quality and final product purity level required affects the design of proces flow and the selection of precise equipment.

For example, a higher purity level may require multi processes aligning with different process equipment and more distillation stages or the use of more advanced technologies. When designing the equipment, it is important to test the feed stream chemical content with chromatography columns and make the best cost-effective technical process flow to meet the process operation target.

The following lists briefly what you need to consider for the technical selection.

1. Test feed stream chemical content to determine the best technical solution for process operation requirements.
2. Consider possible safety hazards and set up proper explosion-proof installation for equipment structure, electric control system, heating system, and cooling system.
3. Wear personal protective equipment, such as gloves and goggles, when recovering and purifying acetone.
4. Work in a well-ventilated area.
5. Avoid open flames and other sources of ignition.
6. Properly disposal standard of waste stream, test the discharging quality of acetone solution frequently to make sure that the disposing quality is acceptable to environmental regulation.

• The Process Flow and Engineering Design

The working conditions of the recovery process, such as feeding temperature, flow rates, heating temperature, working pressure, specific gravity of the material, PH value, utility supply conditions are key parameters for the process engineering design of the complete purification process.

In general, on the basis of completing the process flow design and determining the raw material route and process technology line, further workshop layout design and key parameters of the basic structure of the entire equipment can be obtained, which determines the individual equipment design and piping design and other design tasks.

The core of process design is process flow design, which is the basic outline to achieve high quality, high yield, low consumption and safe production.

Throughout the project, the work of process calculation, equipment selection and equipment layout are directly related to the process flow. All other work can be carried out one after another only after the process flow is determined. Therefore, process flow design is often the earliest to start, but also the latest to end.

The task of process flow design includes two aspects:

1. Determine the specific content of each production process, the sequence and combination of the way to achieve the desired product from raw materials.
2. Draw the process flow diagrams to meet the production process target, from where the raw materials go through each unit operation process to produce the product, when the material and energy changes and its flow direction, and the use of chemical processes and equipment in the form of diagrams, and then further indicate the chemical pipeline process and metering control process through the form of diagrams.

• Safety Production:

It is a question that many customers often ask when purchasing solvent recovery equipment. First when designing the equipment, it is important to consider the possible problems and set up and protect it.

Most organic solvents have the potential to burn and explode during the production process. Everybody knows the three elements of combustion are: oxygen, sparks and combustibles, yet no combustion can occur with any of them. In solvent recovery plants, oxygen and combustibles are present, so the only thing that can be controlled is that there can be no sparks.

Therefore, professional explosion-proof installation must be made in the equipment structure, such as the electric control system is in an airtight explosion-proof housing and grounding installation. The heating system must be explosion-proof set up and the cooling system is also explosion-proof set up to avoid electric sparks.

The Best Technology and Equipment For Acetone Recovery

There are several methods for recovering acetone and purify to high concentration as per customer requirements:

• Continuous Distillation:

Supergravity rotary distillation equipment applies rotary supergravity technology to the continuous distillation process in industrial production. The rotary distillation machine consists of one or more rotors rotating at high speed, and the gas-liquid passes through the rotors in a reverse folding spray manner for material contact mass transfer.

The equipment is widely used in the recovery and separation and purification of organic solvents such as ethanol, methanol, acetone, ethyl acetate, acetonitrile, tetrahydrofuran, methylene chloride, DMF, DMSO, toluene, isopropyl alcohol, tert-butanol, etc.

Up to 500 sets have been industralized used in the industries of API, pharmaceutical intermediates, fine chemicals, biodiesel, environmental protection, brewing, etc.

A supergravity distillation machine of a mere 1.2 meters is equivalent to a conventional 16-meter high distillation column. The working pressure 4Pa, initial concentration range: 20%-90%, qualified product concentration range is 92%-99.5%, processing capacity: 20-30 tons / day.

In the high efficiency rotary distillation machine, the liquid phase undergoes a number of dispersion and aggregation processes, in which the liquid is thrown off the concentric distribution of the moving circle in extremely fine droplets, and under the action of centrifugal force, the droplets moving at high speed are collided, sheared and splashed on specific structures inside the equipment, forming a gas-liquid interface with a large and constantly renewed specific surface, which is brought together and then enters the next cycle.

In the equipment, the process of gas-liquid contact between the annulus of the internal structure of the equipment can be divided into two steps:

1. one step for the liquid phase thrown out of the center, contact with the staggered flow of gas;
2. the second step for the liquid phase in the process of falling on the walls of the specific structure of the equipment, the gas in the annulus rotates upward movement, the liquid is driven by the gas and gravity rotates downward movement, for the counter-current contact.

The second step of the liquid along the wall of the rotational motion and the liquid is constantly thrown out of the collision extrusion, so that the surface renewal is very fast, with double the rate of mass transfer, which is similar to a series of liquid surface renewal is very fast wet wall tower. The equipment inside the gas-liquid goes through a layer of the ring gap is similiar to go through a wet wall tower, with higher mass and heat transfer efficiency.

• Membrane Separation:

Membrane separation uses the difference in permeation rates of organic hydrocarbon substances and other components in polymer or inorganic membranes to achieve the separation of the mixtures.

Organic hydrocarbon substances and inert components are driven by a certain partial pressure difference, Volatile Organic Compounds (VOCs) molecules preferentially pass through the polymer membrane, while inert components such as air or water are trapped and discharged, finally achieving the concentration and enrichment of organic hydrocarbon substances.

For water acetone solution, the zeolite pervaporation membrane dehydration system is highly efficient in trace water removing and purification.

Molecular sieves are crystalline silicates or aluminosilicates, composed of silicon-oxygen tetrahedrons or aluminum-oxygen tetrahedrons, which are connected by oxygen bridges to form a regular pore and cavity system with a molecular size of 0.3-2.0Nm, thus having a sieve molecular properties.

1. Selective adsorption of the separated substance on the membrane surface.
2. Use the various pores of molecular sieve membranes to sieve media with different molecular diameters.
3. Components permeate through the membrane in the form of diffusion.
4. Desorption from the downstream side surface changes to gas phase desorption and separation from the membrane
5. Membrane modules can be used continuously for 3-6 years without regeneration of membrane.

The working process of NaA membrane tube:

When the NaA membrane system vacuumize the inside of the membrane tube to separate water or organic matter, whose diameter is smaller than the molecular sieve channel in the organic liquid flowing through the membrane tube wall as permeate and separate from the raw material liquid.

The permeate is separated from the feed solution by evaporation, gas-liquid separation, and vacuuming of the membrane module in a very simple process. This dehydration process performance can obtain pure acetone content up to 99.99% in industrial scale production plant.

Project Case Study-Acetone Recovery From Synthetic Quinoline Derivatives Wastewater

Quinoline derivatives are increasingly used in medicine, food, additives, etc., The synthesis process of cyclization using aniline and acetone, due to the high cyclization temperature, acetone will be rapidly vaporized after the drop addition into the reaction system, part of the unreacted acetone and the water formed during the reaction separated from the reaction system.

Because acetone and water can be completely miscible, the process generated water must be treated by continuous distillation and pervaporation membrane dehydration system, and the treated high purity acetone can be reused, the reaction water of the process is separated into the wastewater system for treatment.

The acetone content of the process reaction water is 23%-28%, so the recycling of acetone from the process water is of great significance to energy saving and emission reduction.

Analytical method:

Using meteorological chromatography column to analyze the raw material, tower top and tower kettle samples.

According to the water volume of the process reaction generated by the production process and the requirements of the cyclization process, the design of the distillation tower coupling with pervaporation membrane dehydration equipment can obtain acetone of quality content reaches more than 99%, and the acetone content in the wastewater is less a thousand parts. The annual production capacity reaches 8000t/a.

From continuous distillation tower to permeation vaporization dehydration equipment, the whole system realized automatic control of inlet and outlet flow, temperature control, vacuum adjustment, reflux ratio adjustment.

Through system optimization design and improved operation, the energy consumption of the treatment process was reduced to achieve the effect of energy saving and consumption reduction, and the acetone discharge content exceeded the original design index.

Conclusion

Effective acetone recovery and purification can help save costs and reduce environmental impact. By considering the factors before recovery, and choosing the appropriate recovery and purification process and equipment system, and observing safety precautions, one can recover and purify acetone effectively.

Remember, safety should always come first when dealing with chemicals. With this information, you can make informed decisions and contribute to a safe and sustainable environment.

I hope that you have found this post helpful. If you have any questions or comments, please feel free to leave them below. I would be happy to hear from you and to continue the conversation about process equipment for recovery of high purity 99.99% acetone product.