Butadiene to Adipic Acid: A New Process for Nylon Production

05/04/2023

Adipic acid(cas124-04-9) is a key raw material for making nylon, a widely used synthetic fiber and plastic. However, the conventional process for adipic acid production involves harmful chemicals and greenhouse gas emissions. A new process, based on the carbonylation of butadiene, offers a more sustainable and economical alternative.

What is Butadiene?

Butadiene is a hydrocarbon with four carbon atoms and two double bonds. It is obtained from petroleum refining or steam cracking of naphtha. Butadiene is mainly used to make synthetic rubbers, such as polybutadiene, styrene-butadiene rubber, and nitrile rubber. These rubbers have various applications in tires, hoses, belts, and latex products.

How to Convert Butadiene to Adipic Acid?

Adipic acid(cas124-04-9) is a dicarboxylic acid with six carbon atoms and two carboxyl groups at each end. It can be synthesized from butadiene by a two-step reaction involving carbon monoxide and methanol. The first step is the carbonylation of butadiene, which adds a carbon atom and an oxygen atom to each double bond, forming dimethyl adipate. The second step is the hydrolysis of dimethyl adipate, which replaces the methyl groups with hydrogen atoms, forming adipic acid.

What are the Advantages of this Process?

The process of converting butadiene to adipic acid has several advantages over the conventional process, which uses cyclohexane as the starting material and nitric acid as the oxidant. The advantages include:

Higher yield: The process has a reasonably high adipic acid(cas124-04-9) yield (72%) based on butadiene.
Lower cost: The process has a lower raw material cost than the conventional process, especially when dilute butadiene streams are used.
Higher purity: The process produces adipic acid with high purity (99.9%), which meets the requirements for nylon production.
Lower emissions: The process does not produce nitrous oxide, a potent greenhouse gas that is generated by the conventional process.
Better by-products: The process produces methyl valerate and dimethyl esters of C4 dicarboxylic acids as by-products, which could have potential markets or be incinerated if no markets develop. Conclusion
Butadiene to adipic acid is a new process for nylon production that offers environmental and economic benefits. It is based on a two-stage carbonylation reaction of butadiene, carbon monoxide, and methanol, followed by hydrolysis. The process produces adipic acid with high yield, low cost, high purity, and low emissions. The process also generates valuable by-products that could be utilized or disposed of safely.