Activated Carbon Sphere with Antibacterial Characteristics

Abstract

The activated carbon sphere containing zinc oxide was prepared by carbonizing a zinc ion-exchange resin at different temperatures in nitrogen gas. Zinc oxide of hexagonal type was detected in all carbon samples, the amount of which decreased with an increase in the carbonization temperature. However, the specific surface areas of carbon samples increased with increasing temperature of the resin. The antibacterial activity on their carbon samples was studied without the presence of light. The antibacterial activity on carbon samples containing zinc oxide increased with the amount of zinc oxide in the carbon samples. The antibacterial activity for Staphylococcus aureus was stronger than that for Escherichia coli. By an oxygen electrode analysis, it is shown that hydrogen peroxide was generated on the carbon samples. The concentration of hydrogen peroxide increased with increasing carbonization temperature of the resin. The antibacterial activity is found to be caused by the generation of hydrogen peroxide from zinc oxide dispersed in activated carbon sphere.

From zinc oxide nanoparticles to microflowers: A study of growth kinetics and biocidal activity

“…In this regard, metal-oxide nanoparticles like magnesium oxide and zinc oxide have attracted much attention in recent years due to their greater stability under harsh conditions and good antimicrobial activity even in the absence of light [5,6]. Moreover, these particles contain minerals that are essential to human health and hence exhibit higher toxicity toward human pathogens [7].…”

Antifungal Characteristics of Spherical Carbon Materials with Zinc Oxide

“…5), 10) On carbon samples, however, the pH values do not aect the antifungal activity, because of the pH of about 5.7. Yamamoto et al 7) have found the generation of H 2 O 2 from the surface of ZnO in carbon samples and claried that the generated H 2 O 2 was eective for growth inhibition of bac teria. Therefore, the occurrence of antifungal activity in present work is anticipated with the generation of H 2 O 2 , as shown in Fig.…”

Improving the hydration resistance of lime-based refractory materials

“…Reports on the effect of ZrO 2 additions by different investigators [45][46][47][48][49][50][51][52] (Fig. 7) that the densification was promoted by inhibition of growth of CaO grains at a higher temperature (e.g.…”

“…The effects of Al 2 O 3 additive on the properties (apparent porosity, grain growth) and hydration resistance of CaO and CaOcontaining materials have been extensively investigated in relation to sintering temperature and holding time. 8,48,52,69,[73][74][75][76][77][78] Addition of Al 2 O 3 along with SiO 2 and MgO (added or present as impurities) greatly decreases the temperature of liquid formation in the CaO matrix, from 1370uC in the CaO-Al 2 O 3 binary phase diagram to about 1100-1150uC. 77 The dihedral angle between liquid formed by CaO containing a small amount of Al 2 O 3 and CaO refractory is reported to be ,10u.…”

“…Several investigators have detected much improved hydration resistance with Al 2 O 3 additions. 8,48,52,69,[73][74][75][76][77][78] The optimum Al 2 O 3 amount reported by Liu et al 77 was 3 wt-% at a firing temperature .1500uC. A logarithmic relationship between apparent porosity and sintering time was observed.…”