Preparation and characterization of TiO2 based on wood templates.

Titanium dioxide (TiO2) was prepared from four natural wood spices that served as templates. The wood templates were impregnated by a titanium dioxide precursor and then underwent high-temperature calcination to obtain TiO2 with a wood-like hierarchical porous structure. The microstructure of TiO2 based on the wood template was characterized by scanning electron microscopy, X-ray diffraction and nitrogen adsorption-desorption tests. The formaldehyde adsorption and degradation properties of TiO2 based on a wood template are discussed. The results showed that TiO2 based on a wood template could effectively replicate the micro- and mesoscopic pore structure of wood, and the pore size distribution in the TiO2 ranged from 1 to 100 nm. The TiO2 that was prepared based on a wood template showed a certain adsorption effect on formaldehyde under visible light, and the photocatalytic degradation of a formaldehyde solution was achieved when irritated by ultraviolet light. In addition, the properties of the TiO2 prepared by different tree species was also different. The TiO2 prepared by larch and Chinese fir exhibited a large specific surface area, pore volume, and high degradation efficiency of formaldehyde solution. After 280 min of irradiation with an ultraviolet light source, the degradation rates of the formaldehyde solution were 19.91% and 18.85%.

Identification and characterization of odorous volatile organic compounds emitted from wood-based panels.

In studying indoor air quality, the concentration of volatile organic compounds (VOCs) emitted from wood-based panels and products is considered a main influencing factor. VOCs with low concentrations, even below the detection limit, can also have negative effects. Herein, VOCs emitted from particleboards and laminated boards were collected and analysed by GC-MS, and key odorous VOCs were identified using the odor activity value. Compared with laminated boards, particleboards showed higher concentration of total volatile organic compound (TVOC). Halogenated compounds, esters, and aromatic hydrocarbons were main contributors to total VOC emissions, which could relate to the addition of additives used during panel manufacturing. Eleven VOCs were identified that listed as hazardous air pollutants in the US Clean Air Act. Aldehydes were the major contributor to the OAV; most aldehydes have unpleasant odors, such as fatty acids, which contribute to the smell of surrounding air. Octanal was the dominant odorant in the aldehyde compounds.