What is the research progress of the biological synthesis of styrene?

Biological synthesis of styrene research progress?

With the global emphasis on sustainable development and green chemistry, biological synthesis of chemicals has gradually become a research hotspot. As an important chemical raw material, styrene is widely used in the fields of plastics, rubber and resin. The traditional production of styrene mainly depends on fossil resources, which not only consumes a lot of non-renewable resources, but also causes environmental pollution. Therefore, the use of biological synthesis of styrene has attracted much attention. In this paper, the research status of biosynthesis of styrene will be analyzed from the aspects of technical path, research progress and future direction.

1. Biosynthesis of Styrene: Background and Significance

Styrene (C≡H∞CH = CH₂) is an important vinyl monomer, which is widely used in the synthesis of polystyrene, epoxy resin, unsaturated polyester resin and other materials. Traditionally, styrene has been produced primarily by the partial hydrogenation of benzene or the combined reaction of ethylene and benzene. These methods not only rely on fossil fuels, but also produce large amounts of greenhouse gases and harmful by-products, posing a threat to the environment and human health.

The core of biological synthesis of styrene is the use of biocatalysts (such as microorganisms or enzymes) to convert renewable resources (such as glucose, lignocellulose, etc.) into target products. This green chemistry approach has the following advantages:

1. Sustainability: Use renewable resources to replace fossil fuels and reduce dependence on non-renewable resources.
2. Environmental: Biocatalytic processes are usually carried out under mild conditions and pollutant emissions are low.
3. Efficiency: Through genetic engineering technology to optimize the biocatalyst, can significantly improve the product yield and selectivity.

Therefore, the study of bio-synthesis of styrene is of great significance for the sustainable production of chemicals.

2. Biological Synthesis of Styrene Main Technical Path

At present, the research on the biological synthesis of styrene mainly focuses on the following two technical paths:

1. Phenylalanine-based metabolic engineering

Phenylalanine (C-L-H-NO₂) is an aromatic amino acid that contains a benzene ring and a vinyl side chain in its structure. A renewable carbon source, such as glucose, can be converted to phenylalanine by metabolically engineering a microorganism, such as E. coli or yeast. Styrene is then obtained by chemically or biologically deaminating phenylalanine.

In recent years, scientists have optimized the synthetic pathway of phenylalanine through genetic engineering technology. For example, by knocking out or overexpressing the relevant metabolic enzymes, the production of phenylalanine is significantly increased. Using synthetic biology techniques, researchers have developed a variety of "cell factories" to further improve the efficiency of biocatalysis.

2. Based on bio-based propylene oxide route

Propylene oxide (CLEX) is an important industrial chemical that is widely used in the production of materials such as polyurethanes and polycarbonates. Bio-synthesis of propylene oxide and further conversion to styrene is another potential technology path.

Using enzyme catalysis or microbial fermentation technology, scientists have successfully converted renewable resources into propylene oxide. For example, genetically engineered microorganisms can efficiently produce propylene oxide precursor, allyl alcohol. Subsequently, allyl alcohol can be chemically oxidized or epoxidized to form propylene oxide. Finally, propylene oxide is combined with a benzene ring compound to prepare styrene.

3. Biosynthesis of Styrene

At present, the research of biological synthesis of styrene has made remarkable progress, but still faces some technical challenges:

1. Improve product yield and selectivity

Although the yield and selectivity of microorganisms have been significantly improved through metabolic engineering and synthetic biology technologies, further optimization is still needed to reach the level of industrial production. For example, how to reduce the generation of by-products and improve the conversion efficiency of target products is the focus of current research.

2. Reduce production costs

The cost of biological synthesis of styrene depends mainly on the efficiency of the biocatalyst and the scale of production. At present, the yield of laboratory-scale products is high, but in industrial applications, it still faces problems such as large equipment investment and long production cycle. Therefore, the development of high-efficiency, low-cost biocatalysts and the optimization of production processes are key.

3. Explore new biocatalysis methods

In recent years, bioconversion methods based on enzyme catalysis have gradually become a research hotspot. For example, the use of specific enzymes (such as aromatic decarboxylase) to directly convert aromatic compounds into styrene, with high efficiency and strong specificity. Researchers are also exploring the use of photosynthesis or electrochemical biotechnology to further improve the efficiency of biocatalysis.

4. Future Development Direction and Prospects

The research prospect of biological synthesis of styrene is broad, and the future development direction mainly includes the following aspects:

1. Development of efficient biocatalysts

The performance of biocatalysts was further optimized by gene editing and protein engineering. For example, enzymes or microorganisms with higher stability and selectivity are designed to improve the synthesis efficiency of styrene.

2. Explore new reaction mechanisms

Study of novel biocatalytic mechanisms, such as bioconversion processes driven by photosynthesis or electrochemistry. These technologies can not only reduce energy consumption, but also significantly improve the yield of products.

3. Promote industrial application

With the continuous progress of biotechnology, the industrial application of biological synthesis of styrene will become possible. Through the optimization of large-scale fermentation and separation and purification technology, the cost is further reduced and the production efficiency is improved.

5. conclusion

The research progress of bio-synthesis of styrene provides important technical support for green chemistry and sustainable development. Although there are still some technical challenges, the combination of metabolic engineering, synthetic biology and new catalytic technologies is expected to achieve efficient and economical biological styrene production in the future. As the global demand for environmental protection and sustainable development continues to increase, the research and application of biological synthesis of styrene will receive more attention, injecting new vitality into the green transformation of the chemical industry.

Through the above analysis, it can be seen that the research of biological synthesis of styrene has made significant progress in the technical path, process optimization and industrial application. In the future, with further breakthroughs in biotechnology, this field will show greater development potential.