A new wave is surging on a long history of microphase-separated nanostructures in block copolymers as the selfassembled nanostructures leading to industrial use as the coming engineered plastics. Emphasis should be placed on both high reproducibility and mass production of these ordered nanostructures through self-assembling nanofabrication processes, expected as one of the powerful counterparts of the top–down–type nanofabrication such as lithography and beam processing. In 2001 we developed highly reliable nanostructured template film, in which newly designed amphiphilic liquid crystalline block copolymers show normally oriented and hexagonally arranged nanocylinder array structures in meter–sized area thin films. This success satisfies the above requirements applicable to industrial use and also guarantees their high regularity as reliable nanotemplates for structural transcription to and hybridization with various kinds of materials such as metal, semiconductors, and so on. Furthermore, we also introduce the fabrication process of free–standing membranes equipped with fully penetrated straight channels by using a series of amphiphilic liquid crystalline block copolymers, which form normally oriented and hexagonally arranged cylindrical domains with a high aspect ratio up to more than 400.

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Water treatment technology using forward osmosis (FO) membrane has been known since 1970s. However, development for practical use of FO technology is being accelerated all over the world recently, thanks to newly developed FO membranes and the draw solutions. Major application field for FO are energy saving sea water desalination, power generation and waste water treatment. This review gives recent applications of water treatment using FO membranes. For seawater desalination application, a British company has been operating two commercial plants in Oman using FO membrane since 2009. It is reported that they observed stable flux and lower energy consumption compared to RO plant at same site. An American company was awarded energy saving seawater desalination using FO membrane in UAE and will construct a pilot plant. For power generation application, a Japanese company reported that commercial valid plant can be designed using brine from seawater desalination plant and treated waste water in Fukuoka, Japan. A Spanish company and an American university are developing energy saving seawater desalination using pressure retarded osmosis. For waste water treatment, condensation of high TDS waste water in oil and gas industry, has been commercialized using FO membranes by two American companies.

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Water stress, regulation and environmental impact have been driving the need for waste water reuse systems in China in recent years. Especially for industrial activity in water stressed regions, the Chinese government is imposing stringent restrictions to encourage industries to treat and reuse their waste waters. Integrated Membrane Systems (IMS) system is generally used for industrial waste water reuse in China. Some case studies for industrial waste water reuse in China are shown in this paper. These case studies demonstrate the reliable and long term operation of integrated UF+RO operation in commercial cases with challenging water quality requirements, which support the continued development of IMS operations for industrial wastewater reuse applications.

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The 20th century society applied one–pass type urban water system, which brought some issues; the decrease of river water flow owing to massive water intake, centralization of urban wastewater discharge into the receiving waters, high energy requirement for water transport, and adverse effects on human health and aquatic organisms derived from trace chemicals and pathogens in discharge from centralized wastewater system etc. Meanwhile, the quantity of water that is available and accessible can become scarce in the future. Sustainable urban water cycles with reduced carbon footprint is also now becoming a primary goal of water supply and sewage works. Municipal sewage has shifted from a waste to a resource that can recover water, energy, biomass, nutrients and other valuable constituents. We need to seek for more cascaded water system in the 21st century, which will be realized by developing new water treatment technology. Combinations of unit processes using membranes and oxidation technology can make various water applications from various water resources including wastewater. In this research project we evaluated the processes in terms of removal of pathogens, chemicals, toxicity and energy consumption. In addition application of the developed processes to the fields including Okinawa, south China and Vietnam were discussed.

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Recent progresses in inorganic membranes used for water treatment in reverse osmosis (RO) and nanofiltration (NF) are reviewed. Inorganic membranes, which show robust properties, can be used in harsh conditions such as high temperatures, chlorine–containing and acidic solutions. In this review, robust properties required for use in RO/NF are proposed, and then, inorganic RO/NF membranes, including zeolite, sol–gel derived organosilica, carbon- based materials (carbon nanotube, graphene oxide), and CVD–derived silica, are summarized. In addition, possible applications, including reverse osmosis at high temperatures, acid recovery in acid/metal mixture, and chlorine tolerance are introduced.

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In recent years, inorganic membrane, especially zeolite membrane has attracted many attentions because of its possibility of saving energy and reducing CO2 emission in the separation and concentration processes. A new high silica zeolite membrane named ZEBREX TM has high pervaporation performance for the separation of various organic solvent and water mixtures even under acid conditions. In this review article, we report some new applications for liquid separation and gas separation of ZEBREX TM.

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Petroleum products such as gasoline and kerosene are produced from crude oil via the petroleum refining process. The production of these products, which takes place in refineries, involves the use of many kinds of separation technologies. Membrane separation technology could hold the key to less energy–intensive separation processes and more effective use of hydrocarbon resources.

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Silica based membranes were successfully prepared by using a counter diffusion chemical vapor deposition method. The key point to control membrane properties is a silica source which the organic groups connected to Si by the Si–C bond. Ethyltrimethoxysilane (ETMOS), Propyltrimethoxysilane (PrTMOS), Phenyltrimethoxysilane (PhTMOS), Diphenyldimethoxysilane (DPhDMOS) and Hexyltrimethoxysilane (HTMOS) are employed as silica precursors. C3H6/C3H8 permeance ratio was 414 (C3H6 permeance 1.0 × 10–8 mol m–2 s–1 Pa–1) through the membrane prepared by using HTMOS. CH4/C2H6 permeance ratio was 37 (CH4 permeance 2.8 × 10–9 mol m–2 s–1 Pa–1) through the membrane prepared by using ETMOS. C6H6/C6H12 separation factor was 60 with the total flux of 5.6 × 10–3 kg m–2 h–1 through the membrane prepared by using DPhDMOS.

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A strategy focused on water structures near polymer surfaces to develop low–fouling membranes is demonstrated. Based on surveys on the relationships between the antithrombogenic properties of biomaterials and the hydration states of the biomaterial polymers, we supposed that the membranes whose pore surfaces are modified with such polymers having the unique water structures in their hydrated states would have low–fouling properties. In this review, some typical characteristics in water structures of zwitterionic polymers and poly(2–methoxyethylacrylate), both of which are known as excellent biomaterials, are summarized. Then the excellent low–fouling properties of the microfiltration membranes and ultrafiltration membranes modified with carboxybetaine–based polymers and poly(2–methoxyethylacrylate) are demonstrated. These membranes hardly fouled and maintained the initial fluxes when the aqueous solutions containing 1000 ppm BSA were filtered below 6 × 10–6 m3 m–2 s–1 of filtration fluxes.

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Three kinds of diamines, i.e., ethylene diamine (EDA), diethylene diamine (DEDA), and triethylene diamine (TEDA), were immobilized to the poly(glycidyl methacrylate) chain grafted onto a porous hollow–fiber membrane. The resultant anion–exchange porous hollow fibers were evaluated as ion–exchangers for protein binding in a permeation mode. The DEDA– and TEDA–immobilized porous hollow fibers exhibited higher flux for a buffer (pH 8.0) and lower binding capacity for bovine serum albumin than the EDA–immobilized porous hollow fiber. This will be due to that DEDA and TEDA crosslink between neighboring epoxy groups of the graft chain.

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MBR, Membrane Bio Reactor, is an advanced wastewater treatment system which is combination of activated sludge process and membrane separation technology. UF/MF membranes are an alternative of separating solid/liquid which is done by secondary clarifiers in the conventional method. The advantages of MBR are high quality of treated water and smaller footprint in comparison with to the conventional process 1). MBR has received much attention as a technical solution for water conservation. It is the reason why high quality of treated water by MBR is available to water reuse. A major disadvantage of MBR is higher operating cost by comparison with the conventional activated process. And majority of life cycle cost is for air scouring energy. Low aeration demand for air scouring to clean the membrane surface and high membrane flux are significant factors to reduce energy demand of MBR 2). To lower energy demand of MBR, we have developed the compact membrane modules which have 60% higher packing density. And we also have developed the diffuser which can uniformly discharge even less amount of the air for membrane scouring. Based on these techniques, we put “STERAPORETM 5600 series” (2011) and “STERAPORETM 5700 series” (2014) into the market. This paper describes key features and the references of these products and techniques.

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