The partial pyrolysis of hemoglobin yielded the hemoglobin pyropolymer, which is an intermediate substance between a polymer and carbonaceous material. The pyropolymer was formed by the heat treatment of hemoglobin below 600°C. The formation behavior of the pyropolymer was examined by thermogravimetry and differential thermal analysis, and the pyropolymer was characterized by elemental analysis and its 13 C nuclear magnetic resonance spectrum. The pyropolymer formation began around 200°C, and aromatic carbon developed with an increase in the heat-treatment temperature through transformation of the aliphatic carbon in hemoglobin. A noble-metal-free cathode catalyst for a polymer electrolyte fuel cell (PEFC) was formed by heat treatment of the hemoglobin pyropolymer in flowing Ar containing 10% CO 2 . The activity of the catalyst was dependent on the characteristics of the pyropolymer. The carbon matrix developed with an increase in the aromatic carbon, whereas the micropore development was suppressed. The highest activity was observed for the catalyst with the maximized micropore development. The PEFC using the catalyst with the highest activity obtained in this study generated 0.12 and 0.23 W cm -2 at O 2 partial pressures of 54 and 254 kPa, respectively. Continuous PEFC operations and measurements of the extended X-ray absorption fine structures demonstrated that the current decrease during the operation correlated with the structure of the active site of the catalyst.

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Recently, there has been increased demand for a polymer electrolyte fuel cell (PEFC) that functions efficiently with far less or no Pt. In this study, the catalyst for the O 2 reduction at the cathode was formed by carbonizing hemoglobin, which could be abundantly and inexpensively obtained. A substantial enhancement of catalytic properties was achieved by a change in the carbonization process from one step to two steps. The PEFC using the carbonized hemoglobin formed in the modified carbonization process generated a high power comparable to those formed using a Pt-free cathode as reported already. The power densities of 0.11 and 0.16 W cm -2 were attained using H 2 and O 2 gases at atmospheric pressure (H 2 and O 2 partial pressures, 54 kPa) and using pressurized gases (H 2 and O 2 partial pressures, 254 kPa), respectively. The carbonization modification reduced the Fe valence state from 3+ to 2+ in the carbonized hemoglobin, which was demonstrated by X-ray photoelectron spectroscopy. The catalysis enhancement was probably attributed to the increase in Fe(II), which was required as an O 2 bonding site in the first step of the multistep cathodic O 2 reduction process.

Developers used in photolithography contain toxic tetramethylammoniumhydroxide (TMAH) and this creates a problem of how to properly treat developer wastewater. We have developed a TMAH wastewater treatment technique that consists of a combination of two novel decomposition processes: pyrolyzing TMAH to TMA and decomposing TMA to N 2 , H 2 O, and CO 2 by means of a selective oxidation catalyst for nitrogenous compounds. We have tested a system using this technique in long-term treatment of the actual wastewater and have found it to be sufficiently practical. The running cost of a treatment system using our technique would be about one-ninth that of disposing of the wastewater as industrial waste but about 2.3 times that of biological treatment. Compared with biological treatment, however, our system is tolerant to many treatment conditions and operation management is much easier. Furthermore, it occupies only about one-sixth the area of a biological treatment system.