a b s t r a c tChemical activation is a widespread method for activated carbon (AC) preparation, but the removal and recycle of activator from the carbon product are generally a nuisance process. In this study, an environmental benign process, called modified vacuum pyrolysis (MVP) process, was developed for AC production and simultaneous recovery of the activator. The process included two steps: (1) carbonization and activation stage in a vacuum condition; (2) zinc recovery stage in a special temperature and pressure range. In the MVP process, over 99.99 % of the zinc used for activation was recovered in the form of zinc chloride and metallic zinc. The resultant ACs with basic and hydrophobic surface properties displayed higher adsorption capacity for phenol than that of carbons obtained by traditional pyrolysis method. The main merit of the MVP process was that there was no wastewater generation during the whole procedure. Consequently, the experimental data obtained in the present study provided scientific basis for zinc chloride recovery by vacuum pyrolysis during ACs production process.

Fiberglass porous ceramics were prepared via a foam-gelcasting method. The relationship between the rheology of the slurries and the structure of the specimens was investigated. The results show that when the content of the dispersant was 0.25 wt %, the slurries exhibit excellent fluidity. The thixotropic behavior of the slurries was strongly influenced by the content of the foam stabilizer agent and solid content. Furthermore, as the fluidity of the foaming slurries increased, the size of the pores increased. At the same time, the thickness of the pore walls decreased gradually. In addition, promoting the uniform distribution of the pore size by improving the thixotropic behavior of the foaming slurries was beneficial. The optimal foaming slurry was composed of 65 wt % fiberglass, 0.25 wt % dispersant, and 0.1 wt % foam stabilizer agent. After calcination at 750 °C, fiberglass porous ceramics with 78.3% porosity, 2.2 MPa compressive strength, and 0.11 W m −1 K −1 thermal conductivity were obtained.

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