Activated carbon adsorbs perfluorinated compounds (PFCs) in an effluent treatment system at a final disposal site. We examined activated carbon for inorganic fluorine (F) trapped in the gas absorbent obtained by thermal treatment in air followed by combustion decomposition in oxygen flow. The F yields increased as the air temperature rose to 600 °C. The combined yields from combustion pyrolysis in oxygen flow were 215 μg g⁻¹. However, yields decreased at temperatures of 700 °C or greater, probably because of alkaline substances such as calcium carbonate on the activated carbon surface holding F on solid-phase because of the thermal treatment temperature. During experiments, F measurements were conducted using activated carbon washed in distilled water or dilute sulfuric acid. Results show that, with distilled water cleaning, F yields decreased with increasing heat, but with dilute sulfuric acid cleaning, measurements of 106-114 μg g⁻¹ remained unchanged at 500-800 °C. This portion of the total amount of PFCs trapped in activated carbon exhibits about 10 times the concentration of the result of possible PFC identification (5-14 μg g⁻¹) sampled at the same point.

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Current lifestyles using various types of electronic equipment rely on the use of batteries and collection of waste batteries is an important issue. We investigated collection and recycling schemes for waste batteries in Denmark and Switzerland and characterized these schemes, focusing on material flow, monetary flow, and information flow through literature searchs and interviews. We then compared characteristics of the European systems with those of Japan. The European countries were found to collect not only rechargeable batteries but also non-rechargeable batteries and the collection costs were included in the price of batteries. The role of municipalities in collection was much larger than that of Japan, and municipalities were compensated for the collection costs by producers. Based on these observations, we have suggested seven institutional points to promote the collection and recycling of waste batteries in Japan.

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Experiments using persulfate were conducted at 303-348K under normal N₂ pressure to demonstrate the oxidative decomposition of four pharmaceutical products: sulfamethoxazole (SMX), trimethoprim (TMP), theophylline (TPL), and cyclophosphamide (CPA). Time variations in sample concentrations, total organic carbon (TOC) and CO₂ were measured by adding persulfate of 120 molar equivalent to pharmaceutical products in 100mg/L aqueous solution in a lab-scale glass reactor.
Results showed that the pharmaceutical products were decomposed effectively by persulfate at lower temperatures. At 333K, the initial sample decomposition rates were CPA > SMX > TPL > TMP, where the CPA decomposition rate was extremely high. For complete mineralization of CPA, and for that of TMP and SMX at 333K, about 90 min and more than 400 min were needed, respectively. By contrast, TPL showed the greatest difficulty mineralizing. Its mineralization ratio was saturated at about 0.9, even after 400 min reaction time. Moreover, the mineralization ratio of SMX increased from about 0.9 to 0.98 with a rise in temperature from 333 to 348K. Nearly all carbons in SMX were converted to CO₂ with no generation of CO or volatile organic matter.

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A series of cement paste specimens that contained dust-sized granules of blast-furnace slag and particles of waste ceramic insulation were prepared. The proportions (g/g/g) of cement, blast-furnace slag and waste ceramic insulation differed in each specimen. The compressive strength and acid resistance of these materials are examined here. The compressive strength decreased as the proportion of waste ceramic insulation increased. Only two specimens had less than the compressive strength standard in specifications for sulfuric acid-proof mortar used for a corrosion-protection covering layer. The tests showed that the waste ceramic insulation could be added at a ratio of approximately 40% and still exceed the compressive strength standard. Tests of the acid resistance were conducted by immersing the specimens in 5% sulfuric acid, 10% sulfuric acid or artificial acidic sewage. The reaction layer formation of specimens is affected by the blast-furnace slag ratio, waste ceramic insulator ratio, temperature, immersion time and sulfuric acid concentration. The results show that adding waste ceramic insulation controls the dilatability of the reaction layer of the cement paste and improves durability in acidic environments.

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