Core/Shell Nitrogen-Doped TiO2@SiO2 Nano-Catalyst as an Additive in Photocatalytic Paint for Gaseous Acetaldehyde Decomposition

A nitrogen-doped TiO2@SiO2 core/shell nano-photocatalyst (N-TiO2@SiO2) was used as an additive in photocatalytic paint and applied for the photocatalytic degradation of gaseous acetaldehyde under light-emitting diode (LED) visible light irradiation. N-TiO2 was synthesised via the solvothermal method and then encapsulated by SiO2 via the sol-gel method. The incorporation of the N atom into the TiO2 structure was observed by X-ray photoelectron spectroscopy. The N-TiO2@SiO2 core/shell structure was determined by TEM images. The photodegradation of gaseous acetaldehyde using the prepared N-TiO2@SiO2 photocatalytic paint was examined in a closed chamber under LED light irradiation. The photodegradation of acetaldehyde by N-TiO2@SiO2 photocatalytic paint (31%) was significantly higher than that of TiO2 paint (5%) and N-TiO2 paint (20%) within 16 h. The chemical resistance and adhesion ability of N-TiO2@SiO2 photocatalytic paint were investigated following Thai Industrial Standards (TIS) no. 2321 and standard test methods for rating adhesion by tape test (ASTM D 3359-22). The N-TiO2@SiO2 paint showed good acid and alkali resistance, as well as high adhesion ability comparable with commercial paint (without a photocatalyst)

Using Combined Bus Rapid Transit and Buses in a Dedicated Bus Lane to Enhance Urban Transportation Sustainability

Combined bus rapid transit and buses in a dedicated bus lane (CBBD) is a measure that bus rapid transit (BRT) operators implement to reduce overlapping routes between BRT and fixed-route buses. The CBBD measure can combine the passengers of both systems on the same route, which helps increase passenger demand for the BRT, and reduce fuel consumption and emissions from utilizing the exclusive lanes for the combined route. However, the CBBD could affect some bus and BRT passengers in terms of either losing or gaining travel time-saving benefits depending on their travel pattern. This research proposed a methodology to determine the travel distance initiating disadvantage for BRT passengers (DDB) to justify the potential success of the CBBD operations. The number of passengers gaining a benefit from the CBBD was sensitive to the distance between the CBBD stops and the operational period of the CBBD. The CBBD reform would be beneficial to transit agencies to improve the travel time of passengers and be able to promote environmental sustainability for the public transportation system in urban cities

Analysis of nitrogen and carbon tetrachloride adsorp- tion isotherms and pore size distribution for siliceous MCM-41 synthesized from rice husk silica

o C using a magnetically coupled microbalance, and compared with adsorption isotherms using nitrogen at 77 K. The CT isotherms were classified as reversible Type V isotherms, and the nitrogen adsorption isotherm was Type IVc. Capillary condensation was found in a very narrow pressure range, indicating the presence of nearly uniform pores in the RH-MCM-41 particles, which agrees very well with TEM results. The surface area estimated by using the BET method was (800 ± 8) m 2 g -1 . Pore size distributions (PSD) of nitrogen and CT adsorption isotherms for a series of MCM-41 were calculated by using method recommended by Naono and Hakuman (1997). The pore size distributions from the nitrogen isotherm using the BJH and Naono methods showed quite narrow pore diameter distributions, centered around 27 and 29 Å, respectively. Similarly, the peak pore diameters calculated from CT isotherms using the BJH and Naono methods were 24 and 28 Å. It was found that the PSDs analyzed by the BJH method were underestimated compared to that from Naono method

Wood Substitute Material from Coconut Shell Waste and Green Adhesive

This research aimed to utilise coconut shell waste as a raw material to produce compressed coconut shell sheets by using environmentally friendly adhesive from epoxidized natural latex and gelatinized tapioca starch. The coconut shells were cut into 1-mm particles and mixed with the adhesive. The mixture was then compressed in a 30×30×0.5 cm mould using a hydraulic compression machine at 5 MPa and 170°C for 5 minutes to form a compressed coconut shell sheet. The different ratios of adhesive to coconut shell particles (30, 40, and 50 g) per 100 g of coconut shell and the different ratios of gelatinized tapioca starch and epoxidized natural rubber (ranging from 1:0, 1:1, 2:1, 3:1, to 4:1 by weight) were examined. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were employed to analyse the morphology and chemical composition of the coconut shell sheets, respectively. The physical and mechanical properties of the compressed coconut shell sheets were evaluated based on the Thai Industrial Standard (TIS) number 876-2547 for flat pressed particleboards. The results demonstrate successful production of compressed coconut shell sheets from coconut shell waste using the environmentally friendly adhesive. ENR played a role in networking between lignin and cellulose. While GTS improved the strength of the composite using hydrogen bonding. The optimal ratio of adhesive to coconut shell particles was 40 g of the green adhesive per 100 g of coconut shell. The optimal ratio of gelatinized tapioca starch to epoxidized natural rubber was 2:1 by weight. The coconut shell sheets produced from this study were uniform in shape, had unique textures, and met industry standards for wood substitute materials

Core/Shell Nitrogen-Doped TiO₂@SiO₂ Nano-Catalyst as an Additive in Photocatalytic Paint for Gaseous Acetaldehyde Decomposition

A nitrogen-doped TiO2@SiO2 core/shell nano-photocatalyst (N-TiO2@SiO2) was used as an additive in photocatalytic paint and applied for the photocatalytic degradation of gaseous acetaldehyde under light-emitting diode (LED) visible light irradiation. N-TiO2 was synthesised via the solvothermal method and then encapsulated by SiO2 via the sol-gel method. The incorporation of the N atom into the TiO2 structure was observed by X-ray photoelectron spectroscopy. The N-TiO2@SiO2 core/shell structure was determined by TEM images. The photodegradation of gaseous acetaldehyde using the prepared N-TiO2@SiO2 photocatalytic paint was examined in a closed chamber under LED light irradiation. The photodegradation of acetaldehyde by N-TiO2@SiO2 photocatalytic paint (31%) was significantly higher than that of TiO2 paint (5%) and N-TiO2 paint (20%) within 16 h. The chemical resistance and adhesion ability of N-TiO2@SiO2 photocatalytic paint were investigated following Thai Industrial Standards (TIS) no. 2321 and standard test methods for rating adhesion by tape test (ASTM D 3359-22). The N-TiO2@SiO2 paint showed good acid and alkali resistance, as well as high adhesion ability comparable with commercial paint (without a photocatalyst)

Photocatalytic Improvement under Visible Light in TiO2 Nanoparticles by Carbon Nanotube Incorporation

Photocatalytic activity of TiO2 nanoparticles was successfully enhanced by addition of multiwall carbon nanotubes (MWCNT) to make CNT/TiO2 nanocomposites by sol-gel method at ambient temperature. CNT treated by HNO3 : H2SO4 treatment (1 : 3 v/v) was mixed with TiO2 nanoparticles at various molar ratios and calcination temperatures. The optimal molar ratio of CNT : TiO2 was found at 0.05 : 1 by weight. The optimal calcination condition was 400°C for 3 h. From the results, the photocatalytic activities of CNT/TiO2 nanocomposites were determined by the decolorization of 1 × 10−5 M methylene blue (MB) under visible light. CNT/TiO2 nanocomposites could enhance the photocatalytic activity and showed faster for the degradation of MB with only 90 min. The degradation efficiency of the MB solution with CNT/TiO2 nanocomposite achieved 70% which was higher than that with pristine TiO2 (22%). This could be explained that CNT prevents TiO2 from its agglomeration which could further enhance electron transfer in the composites. In addition, CNT/TiO2 nanocomposites had high specific surface area (202 m2/g) which is very promising for utilization as a photocatalyst for environmental applications