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Adhesive application in indoor decoration is an important anthropogenic volatile organic compound (VOC) emission source of both indoors and outdoors. However, few studies have been conducted on VOC emission factors and characteristics from indoor decorating adhesives. In this study, the VOC emission factors were obtained by measurement of VOCs in 210 adhesives. The results showed that the VOC emission factors were 41.23 g/L for wall and ground solidify, 33.49 g/L for tile adhesive, 76.88 g/L for white glue, 52.36 g/L for wallcovering adhesive, 132.28 g/L for sealant glue, 49.33 g/kg for foaming adhesive, 654.23 g/L for all-purpose adhesive, 251.93 g/L for free nails adhesive, 152.01 g/L for marble glue, and 136.79 g/L for beautiful sealant. Methodology for calculating activity data of decorating adhesive consumptions was developed and a VOC emission inventory from adhesive application in indoor decoration was developed using a bottom-up estimation methodology. The VOC emissions from 2012 to 2017 in China were 235,987.76, 246,230.47, 250,981.62, 249,849.48, 227,150.33 and 212, 433.07 t, respectively. The beautiful sealant, wall and ground solidify, sealant glue and all-purpose adhesive contributed the most of the total emissions, collectively accounting for 78.14%. Shandong, Jiangsu, Zhejiang, Sichuan and Guangdong ranked as the top five provinces for VOC emissions, together contributing 39.10% to the national total emissions. Shandong and Jiangsu reached up to 17,057.95 t/year and 15,207.92 t/year, respectively. Priority should be given to four types of adhesives with pretty high VOC contents for designing effective VOC control measures, including solvent-based all-purpose adhesive, solvent-based free nails adhesive, solvent-based sealant glue, and solvent-based beautiful sealant. Future emission trends are projected through 2030 based on current emission control policies and real estate trend. It may be possible to reduce VOC emissions by 60.81% and 69.37% by 2030 under the two scenarios, respectively, compared with the VOC emissions in 2017.

Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC (black carbon) samples. TEM (transmission electron microscopy) results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET (Barrett-Emmett-Teller) results suggest that the surface areas of these BC particles fall in the range of 3-23 m(2)/g, with a total pore volume of 0.03-0.05 cm(3)/g and a mean pore diameter of 7-53 nm. The nitrogen adsorption-desorption isotherms are indicative of the accumulation mode and uniform pore size. O-2-TPO (temperature programmed oxidation) profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406-490 degrees C with peaks at 418, 423 and 475 degrees C, respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site. (C) 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.

The ozonation of synthetic wastewater containing azo dye Acid Red 14 (AR 14) was investigated in a high-throughput microporous tube-in-tube microchannel reactor. The effects of design and operating parameters such as micropore size, annular channel width, liquid volumetric flow rate, ozone-containing gas volumetric flow rate, initial pH of the solution and initial AR 14 concentration on decolorization efficiency and ozone utilization efficiency were studied with the aim to optimize the operation conditions. An increase of the ozone-containing gas or liquid flow rate could greatly intensify the gas–liquid mass transfer. Reducing the micropore size and the annular channel width led to a higher mass transfer rate and was beneficial to decolorization. Decolorization efficiency increased with an increasing ozone-containing gas volumetric flow rate, as well as a decreasing liquid volumetric flow rate and initial AR 14 concentration. The optimum initial pH for AR 14 ozonation was determined as 9.0. The degradation kinetics was observed to be a pseudo-first-order reaction with respect to AR 14 concentration. The difference between the decolorization and COD removal efficiency indicated that many intermediates existed in AR 14 ozonation. The formation of six organic intermediates during ozonation was detected by GC/MS, while the concentration of nitrate and sulfate ions was determined by ion chromatography. The possible degradation mechanism of AR 14 in aqueous solution was proposed.