http://publicationslist.org/data/meng.chong/ref-18/sdarticle.pdf

Recent Developments in Photocatalytic Water Treatment Technology: A Review

Sulfate radical-based advanced oxidation processes (SR-AOPs) employing heterogeneous catalysts to generate sulfate radical (SO4 −) from peroxymonosulfate (PMS) and persulfate (PS) have been extensively employed for organic contaminant removal in water. This article aims to provide a state–of–the–art review on the recent development in heterogeneous catalysts including single metal, mixed metal, and nonmetal carbon catalysts for organic contaminants removal, with particular focus on PMS activation. The hybrid heterogeneous catalyst/PMS systems integrated with other advanced oxidation technologies is also discussed. Several strategies for the identification of principal reactive radicals in SO4 −–oxidation systems are evaluated, namely (i) use of chemical probe or spin trapping agent coupled with analytical tools, and (ii) competitive kinetic approach using selective radical scavengers. The main challenges and mitigation strategies pertinent to the SR-AOPs are identified, which include (i) possible formation of oxyanions and disinfection byproducts, and (ii) dealing with sulfate produced and residual PMS. Potential future applications and research direction of SR-AOPs are proposed. These include (i) novel reactor design for heterogeneous catalytic system based on batch or continuous flow (e.g. completely mixed or plug flow) reactor configuration with catalyst recovery, and (ii) catalytic ceramic membrane incorporating SR-AOPs.

Generation of sulfate radical through heterogeneous catalysis for organic contaminants removal: Current development, challenges and prospects

Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

Complex Hydrides for Hydrogen Storage

Application of peroxymonosulfate and its activation methods for degradation of environmental organic pollutants: Review

Reports that promote persulfate-based advanced oxidation process (AOP) as a viable alternative to hydrogen peroxide-based processes have been rapidly accumulating in recent water treatment literature. Various strategies to activate peroxide bonds in persulfate precursors have been proposed and the capacity to degrade a wide range of organic pollutants has been demonstrated. Compared to traditional AOPs in which hydroxyl radical serves as the main oxidant, persulfate-based AOPs have been claimed to involve different in situ generated oxidants such as sulfate radical and singlet oxygen as well as nonradical oxidation pathways. However, there exist controversial observations and interpretations around some of these claims, challenging robust scientific progress of this technology toward practical use. This Critical Review comparatively examines the activation mechanisms of peroxymonosulfate and peroxydisulfate and the formation pathways of oxidizing species. Properties of the main oxidizing species are scrutinized and the role of singlet oxygen is debated. In addition, the impacts of water parameters and constituents such as pH, background organic matter, halide, phosphate, and carbonate on persulfate-driven chemistry are discussed. The opportunity for niche applications is also presented, emphasizing the need for parallel efforts to remove currently prevalent knowledge roadblocks.

/pdf/persulfate-based-advanced-oxidation-critical-assessment-of-ru3om4hbrg.pdf

Persulfate-Based Advanced Oxidation: Critical Assessment of Opportunities and Roadblocks.

Carbon fibre-reinforced lithium aluminosilicate matrix composites (Cf/LAS) with different SiB6 contents were prepared by the hot pressing method to assess their mechanical properties and oxidation resistance. Composite that was incorporated with 2 wt-% SiB6 exhibited the highest flexural strength of 500 ± 22.3 MPa. Weight loss and residual strength of Cf/LAS modified by SiB6 were analysed. The results indicated that the addition of SiB6 had a remarkable effect on improving the oxidation resistance for Cf/LAS. To establish a direct relationship among interfacial microstructure, mechanical and oxidation behaviour of the studied composites, their connection was examined and discussed.

Enhanced mechanical properties of carbon fibre/lithium aluminosilicate composites modified by SiB6 addition

A sludge ozonation process with lab-scale anaerobic/oxic (A/O) system was used to investigate the utilization of the ozonized sludge (OS) supernatant as extra carbon source for denitrification. The optimal ozone dose for the sludge ozonation was 0.2 gO(3)/gSS. The concentrations of SCOD, BOD, NH(3)-N and TN in the supernatant increased respectively at this ozone dose. In the meantime, the sludge was significantly reduced. The OS supernatant had negative effect on nitrification because of low pH and alkalinity. After alkalinity adjustment, the A/O with the OS supernatant as the extra carbon source achieved a nitrogen removal rate of 78%, which was very close to the control experiment using glucose (79%).

Biological Nitrogen Removal Using the Supernatant of Ozonized Sludge as Extra Carbon Source

Metal-doped mesoporous silica as sulfur hosts in lithium‑sulfur battery with enhanced conductivity and polysulfide adsorption ability

Wickless gravity loop thermosiphons (LTs) have been widely used in heat collection for distances up to several meters. This two-phase closed device, which is operating under reduced pressure, is useful in solar water heating (SWH) systems because it could address the freezing problem during winter. Compared to the normal type, forced-circulation wickless LTs have significant advantages in the long-distance heat transfer and installation freedom of condensation section. In this study, a pump-forced wickless LT-SWH system with a remolded flat-plate solar collector was put forward. Solar collector acted as the evaporation section of the wickless LT, while the spiral heat exchanger in the water tank acted as the condensation section. R600a was employed as the working fluid, and long-term outdoor experiments were carried out. Results show that the instantaneous and daily average photothermal efficiency of the proposed system can reach 69.54% and 58.22%, respectively. Temperature differences between the top and bottom and the middle and bottom of the evaporation section of the wickless LT were small, and it usually ranged between 1.1 and 3.9°C. Linear fittings of the collector and system overall performance of the pump-forced wickless LT-SWH system demonstrate the promising potential application of the system.

/pdf/experimental-study-on-a-forced-circulation-loop-thermosiphon-50fdgk90ip.pdf

Experimental Study on a Forced-Circulation Loop Thermosiphon Solar Water Heating System

Carbon fibers reinforced lithium aluminosilicate matrix composites (Cf/LAS) were prepared by slurry infiltration combined with a hot press procedure. The friction, wear behavior, and wear mechanisms of Cf/LAS composites under dry sliding conditions were investigated. The results show that the coefficient of friction (COF) initially increased with the increase in carbon fiber content, and reached the maximum value of 0.20 for the 33%Cf/LAS composite. The COF increased sharply with increasing sample temperature from RT to 300 °C. The COF remained stable in the temperature range of 300–500 °C. The two wear mechanisms of LAS glassceramics are fatigue wear and abrasive wear. The Cf/LAS composites demonstrate slight spalling and shallow scratches. These results show that carbon fibers improve the mechanical properties and wear resistance of Cf/LAS composites.

/pdf/friction-and-wear-behavior-of-carbon-fiber-reinforced-3ho26zudpd.pdf

Tao Zhang

Papers

Enhanced mechanical properties of carbon fibre/lithium aluminosilicate composites modified by SiB6 addition

Biological Nitrogen Removal Using the Supernatant of Ozonized Sludge as Extra Carbon Source

Metal-doped mesoporous silica as sulfur hosts in lithium‑sulfur battery with enhanced conductivity and polysulfide adsorption ability

Experimental Study on a Forced-Circulation Loop Thermosiphon Solar Water Heating System

Friction and wear behavior of carbon fiber reinforced lithium aluminosilicate composites sliding against GCr15 steel