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Research paper−151−Synthesiology - English edition Vol.3 No.2 pp.151-161 (Sep. 2010) recyclable resources such as the biomass should be set at the core. This means the realization of distributed production with multi-purpose low-volume production. To achieve this, establishment of highly controllable compact processes with high-speed reaction is desired. The compact process here means a safe, flexible, and efficient process with low environmental load, where the cycling of resource and energy can be done easily. It also must have high-speed and highly controllable performance, enabling low-volume production at distributed sites.The microreactor is gaining attention as the core technology of the low-volume distributed production due to its compactness and the precise controllability of its reaction field[1]. In general, it is a device for conducting chemical reaction in a microspace of width from a few m to a few hundred m. It is categorized into the microreactor, micromixer, and micro heat exchanger according to its purpose and function. The microreactor has large surface area per unit volume (specific surface area), and therefore has extremely high heat exchange efficiency, and allows rapid temperature operation (heating and cooling) and precise temperature control. The large specific surface area of the reactor means that the reaction occurs at the interface efficiently. Also, since the micro flow channel has short diffusion distance, mixing by molecular diffusion occurs rapidly, and high-speed and efficient mixing takes place. These characteristics fulfill the conditions (high speed and high controllability) required in the compact process. However, the conventional microreactor is composed largely of materials that can be processed easily such as silicon, glass, and plastic, and cannot be used in high-temperature and/or high-pressure conditions, where the property of the 1 Background and objective of the researchThe large-scale production at concentrated sites that forms the core of the chemical industry has significantly raised the modern living standard, and brought great wealth in the latter half of the 20th century. By using this method, the product cost was decreased dramatically, and excellent products became reasonably available to many people. In general, the production cost is said to increase approximately at the power of 0.6 of the production volume. According to this rule of scale-up, the production cost for 1,000 yen/kg will become 10 yen/kg at a production scale 100,000 times greater (105×0.6 ÷ 105 = 10-2). The dramatic economic impact of the large-scale production at concentrated sites lead to the expansion (scaling up) of production scale in various fields. However, this system assumes the one-directional use of a large amount of fossil resources, it is extremely difficult to create a material cycling system since it is difficult to balance the recovery and reuse. On the flip side to mass-production, there were the issues of mass consumption (depletion) of fossil resource, immense energy consumption due to the global transportation of fossil resource, and generation of substantial wastewater and waste products. These are inducing various environmental problems such as global warming and organic pollutant contamination.In order to realize sustainable development, it is anticipated that industrial structure, social and technical systems based on large-scale production at concentrated sites dependent on fossil resources must be changed in the near future. Specifically, it is essential to create a safe, flexible, and efficient process with low environmental load, where cycling of resource and energy can be done easily, and the use of - Integration of high-pressure micro-engineering and supercritical fluid -Akira Suzuki*, Hajime Kawanami, Shin-ichiro Kawasaki and Kiyotaka HatakedaResearch Center for Compact Chemical System, AIST 4-2-1 Nigatake, Miyagino-ku, Sendai 983-8551, Japan *E-mail : Original manuscript received December 11, 2009, Revisions received April 5, 2010, Accepted April 7, 2010In order to realize sustainable development, it is anticipated that industrial structure, social and technical systems based on large-scale production at concentrated sites must be changed in the near future. Establishment of highly controllable compact processes with high-speed reaction is desired to realize distributed production with multi-purpose low-volume production. Integration of high-pressure microengineering and supercritical fluid has received considerable attention as a core technology for compact processes. To realize the technology, basic developments for high-pressure microengineering such as rapid heat exchange and precise temperature control were firstly needed, and then process developments on basic engineering followed. As applications of compact processes, organic synthesis under supercritical water is discussed, and inorganic synthesis and an innovative coating process using supercritical carbon dioxide are also described. Establishment of compact processesKeywords : Low-volume production at distributed sites, compact process, micro-reactor, supercritical fluid, rapid heat exchange[Translation from Synthesiology, Vol.3, No.2, p.137-146 (2010)]

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