Progress on non-petroleum-based synthesis of adiponitrile
Adiponitrile is the precursor for nylon-66 production,and its synthesis relies heavily on petroleum resources.In recent years,fluctuating oil prices and geopolitical factors have caused huge uncertainty in adiponitrile supply,severely hindering the stable development of nylon-66 industry.Hence,scientists in China have been motivated to explore alternative synthesis routes from non-petroleum resources with independent intellectual property rights.This issue has been selected as one of the top ten industrial technology issues of the China Association for Science and Technology in 2022,reflecting the urgency and significance of the research topic.Conventional adiponitrile synthesis methods generally suffer from high energy consumption and complex processes.Even after years of optimization,the most advanced direct cyanide method for butadiene still cannot avoid the problem of waste generation.Moreover,foreign corporations have accumulated extensive experiences through long-term deficit operations,which continuously improved the technology and reduced costs.Simply following existing processes can hardly make any breakthrough.Thus,completely new synthesis strategies must be developed to achieve the technological advancements.In recent years,a variety of new techniques such as microreactor synthesis,advanced catalyst design,and coproduction technology emerged,and they have provided novel ideas for the design of the new adiponitrile synthesis routes.Thus,it is necessary to comprehensively analyze the recent progresses to identify the core scientific challenges.By conducting fundamental research to tackle these problems,it is promising to transform the advanced but immature strategies into practical processes.This paper comprehensively reviews the latest research progresses on adiponitrile synthesis from non-petroleum feeds,systematically summarizing various synthesis strategies based on renewable resources like biomass,coal and natural gas,as well as different methods employing enzymatic,electrochemical,and chemical catalysis to produce adiponitrile.The paper not only summarizes the corresponding reaction ways of each method,but also envisions multiple new pathways worth developing based on the advantages and limitations of current routes.It further explores the future research hotspots and application prospects in the field,and provides a comprehensive review and scientific support for developing novel adiponitrile synthesis methods.(1)Adiponitrile synthesis from biomass:This section reviews the reports on the synthesis of adiponitrile intermediates from cellulose and sugar and the direct electrochemical synthesis of adiponitrile from glutamic acid.Under this strategy,5-hydroxymethylfurfural is an important intermediate for adiponitrile synthesis via condensation and amination reactions.Biomass can also generate C4 compounds like butadiene for subsequent adiponitrile synthesis.Although the present technologies suffer from the low yields and complex processes,there are sufficient space for improvements owing to the recent advances of biotechnologies.(2)Adiponitrile synthesis from coal:This section introduces the synthesis of adiponitrile from coal-based chemicals such as ε-caprolactone.There are also methods to produce acetylene from coal,being followed by the subsequent conversion to C4 and C6 compounds,and the cyanation reaction.These methods are relatively mature,but the issues of low product yield and solid waste generation still need to be addressed.(3)Adiponitrile synthesis through new resources:Alternative methods for adiponitrile synthesis using novel resources such as carbon dioxide,natural gas,and organic wastes may be developed in future.Solar energy can be employed to convert carbon dioxide into synthesis gas,which then leads to adiponitrile after steps of reactions.Similarly,natural gas can be employed to produce methanol,which is then converted into 1,3-butadiene for adiponitrile production.Thermally decomposing discarded nylon materials may also lead to the precursor for adiponitrile synthesis.These are environment-benign protocols.
NETL
NSTL
万方数据
维普
