Research on soot of black smoke from ceramic furnace flue gas: characterization of soot.

In this study, the characterizations of soot from ceramic furnace flue gas were studied using environmental scanning electron microscopy, energy dispersive spectroscopy, particle size distribution, specific surface area measurements, crystal characterizations and organic pollutant analysis. Soot particles were mainly spherical nanoparticles with diameters less than 100 nm. However, the particles could be aggregated into larger ones with a median diameter of 3.66 µm. Nanometer pores with diameters ranging 2-4 nm were also detected in the soot particles. Because of their large surface areas and pore volumes, other pollutants in the environment can be adsorbed to soot particles potentially making them more hazardous. Several elements, including C, O and Pb, were detected in the soot, but only small amounts of crystalline materials were observed. This is because most of the detected carbon and metals/metal oxides/metal salts were amorphous. Approximately 90 different organic pollutants were detected in the soot, including aromatic compounds and other hydrocarbons. Because of the carcinogenic properties of aromatic compounds and the photochemical effects of hydrocarbons, soot could have serious health and environmental impacts. The results suggest that soot particles are hazardous material and urgently need to be controlled.

[Study on the mathematic model about surfactants screening used for smoke wet purification].

Surfactants increase wetting, solubilization of carbon black and reduce interfacial tension between surfactants and carbon black are very important for the wet removal of furnace smoke. Calculated hydrophile-lipophile balance value (HLB), critical micelle concentration (CMC) and Gibbs-free-energy (deltaG0(mf)) of mixed surfactants solution generated on the basis of selected mathematical models. The CMC of AEO-9, SDBS solution at different ratios and smoke removal efficiency at the CMC were gained by experiments. The relation among HLB, CMC and deltaG0(mf) in mixed surfactants were analyzed. At last, new mathematic models were established about them. The results showed that the calculated data had good agreement with the experimental data. HLB was linearly correlate with ln [CMC]. There was a quadratic relationship between deltaG0(mf) and smoke removal efficiency. The reducing CMC could effectively increase HLB value and solubility, while the deltaG0(mf) and surface tension were both decreased, which could form micelles more spontaneously and enhance smoke removal significantly.