Cellular SCR denitration catalyst will partly or entirely loss activity after being used for some time, thus cannot to be effective and bring out a lot of waste catalysts. If we don’t recover the noble metals such as titanium, tungsten, and vanadium in the catalysts, it will inevitably result in resources wasted, environmental pollution and costs increased.

 

If we can change waste into treasure, which means recovering the waste catalysts as raw materials for producing catalyst, making these materials circulating, we guess it would be a very good approach. A method that recovering powder containing tungsten trioxide from waste cellular SCR denitration catalyst have been pointed out. The steps are as follows:

 

1. Crushing: Crushing the waste SCR denitration catalyst into 30~50mm pieces by a crusher, and also clearing away the ash by a shaker;

2. Cleaning: Cleaning the catalysts after crushing by an ultrasonic for 1 hour, and then washing by water; 

3. Drying: Drying the catalyst after cleaning in an oven at 100-150°C for 10~15 hours;

4. Grinding: Grinding the dried catalyst into powder with particle size of 5-50um, then the waste SCR denitration catalyst containing tungsten trioxide obtained.

 

The recovered waste SCR denitration catalyst containing tungsten trioxide can be reused as the material for producing fresh catalyst, thus to achieve the goal of recycling. The implementation is: mixing the raw materials titanium dioxide, glass fibers, waste SCR denitration catalyst recycled material, tungsten trioxide, vanadium pentoxide and deionized water, after kneading, extruding, drying and calcining to prepare SCR denitration catalyst.

A systematic investigation of the synthesis of homogenous CsxWO3 nanorods by a designed water-controlled release process was carried out. The results revealed that the uniform rod-like CsxWO3 nanoparticles with a Cs/W atomic ratio of ca. 0.33 can be obtained by using 20 vol% CH3COOH–80 vol% CH3CH2OH mixed solution as a reaction solvent at 240 °C for 20 h. 

 

The morphology of products were changed depending on the speed of water-releasing process, meanwhile, the Cs/W atomic ratio could be controlled by both the amount of released water and the reaction temperature. CsxWO3 nanorods showed a high transmittance in the visible light region and excellent shielding ability of near infrared (NIR) lights, indicating that CsxWO3 nanorods have a suitable characteristic as solar filter applications.

Recently, photothermal ablation therapy (PTA) employing near-infrared radiation (NIR) has been extensively investigated as an emerging modality for cancer management. However, the clinical translation of this promising approach is limited by the lack of PTA agents with broad NIR absorption, low cost and high photothermal conversion efficiency. Herein, the developed PEGylated homogeneous CsxWO3 nanorods (a mean size ∼69.3 nm × 12.8 nm) with broad photo-absorption (780-2500 nm) as a novel NIR absorbent for PTA treatment of human cancer. The prepared CsxWO3 nanocrystals displayed strong near-infrared optical absorption with a high molar extinction coefficient (e.g. 4.8 × 10(10) M(-1) cm(-1) at 980 nm), thus generated significant amounts of heat upon excitation with near-infrared light. The PTA study in two human carcinoma cell lines (i.e. A549 lung cancer cells and HeLa ovarian cancer cells) demonstrated that CsxWO3 nanorods can efficiently cause cell death via hyperthermia induced lysosome destruction, cytoskeleton protein degradation, DNA damage and thereafter cellular necrosis or apoptosis. 

 

The study also confirmed the migration of healthy cells migrated from unirradiated areas to dead cell cycle, which is essential for tissue reconstruction and wound healing after photodestruction of tumor tissue. The prompted results reported in the current study imply the promising potential of CsxWO3 nanorods for application in PTA cancer therapy.

 

Cesium tungsten bronze (Cs_xWO₃) powders were synthesized by hydrothermal reaction at 190 °C by using sodium tungstate and cesium carbonate as raw materials, and the effects of N₂ annealing on the microstructure and near-infrared (NIR) shielding as well as heat insulation properties of Cs_xWO₃ were investigated. The results indicated that the synthesized Cs_xWO₃ powders exhibited hexagonal Cs_0.32WO₃ crystal structure, and subsequent N₂ annealing could further improve the crystallinity of Cs_xWO₃ particles.

Moreover, the NIR shielding and heat insulation properties of Cs_xWO₃ could be further improved after N₂ annealing at appropriate temperature for a period of time. Particularly, the 500 °C-annealed Cs_xWO₃ products in the N₂ atmosphere showed the best NIR shielding and heat insulation properties. When the N₂ annealing temperature was higher than 700 °C, the NIR shielding properties decreased again. The 800 °C-annealed samples in the N₂ atmosphere showed higher visible light transmittance, however, the NIR shielding properties were lower than that of the non-annealed samples.