Spent SCR Catalyst Leach Liquor Processed for Valuable Metals Extraction by Solvent Extraction Technique#

Abstract

Selective catalytic reduction (SCR) has been a promising technology to reduce the air pollution caused by nitrogen oxides (NOx) in several industries. The consumption of SCR catalysts increases every year as technology evolves, however those have a limited lifespan and usually end up in landfills after they deactivate. Currently, the most widely used catalyst for and stationary applications is V 2 O 5 -WO 3 /TiO 2 which can contain around 50% wt V 2 O 5 and 7-10% wt of WO 3 . The vast uses for both vanadium 56

Rationalizing Graphene–ZnO Composites for Gas Sensing via Functionalization with Amines

“…Extrapolating the acquired SNR(C) towards the cap of SNR = 3, corresponding to the minimum practical level of signal detection, the limit of detection (LOD) was determined to be 5.1 ppm, 3.6 ppm, and 1.3 ppm for NH 3 , C 2 H 5 OH, and H 2 O, respectively. These values are among the most commonly reported for state-of-the-art graphene-based gas-sensing devices (Supplementary Materials, Section S6) and already fit almost all practical demands for the detection of ammonia and alcohols [7,8,[14][15][16]18,27,[79][80][81]. To further manifest the operation of the fabricated multisensor chips under various conditions, the chemiresistive response of the on-chip sensor arrays composed of AmG and Am-ZnO layers toward NH3 and C2H5OH mixed with humid air was recorded and examined.…”

“…The nature of the second peak is more disputable. Commonly, it is attributed to oxygen vacancies in ZnO nanoparticles [16,57], which, if located on the surface of the ZnO nanoparticles, form dangling bonds. However, Frankcombe et al found this to be a misinterpretation, instead attributing the spectral component at these BEs to the OH-related species [58].…”

“…400 cm 2 •V −1 •s −1 [14]. Moreover, ZnO has the advantages of biocompatibility, chemical stability, environmental friendliness, and low synthesis cost [15,16]. Exhibiting a decent sensitivity level while operating at room temperature or slightly higher, composites based on graphene and other 2D materials bearing ZnO NPs showing advantages in the fabrication of miniaturized, robust, and low-power gas-sensing instrumentation for various practical applications, particularly for dealing with Internet-of-Things tasks [17].…”

Separation of Uranium(VI) and Vanadium(V) from Sulfuric Acid Media by Amine Based Extractants through Liquid-liquid Extraction Technique#

“…The latest available studies show very limited attempts for the vanadium extraction by amine-based extractants [13][14][15][16][17][18] ; in addition, there is only a few reported research papers available for the separation technology between uranium and vanadium.…”