Sol-gel process with continuous ultrasonication was used to produce pure and vanadium doped titania powders. The amount of vanadium doped in titania was varied by using different initial concentrations of vanadium solutions. Scanning electron microscopy and particle size analyses showed formation of spherical shaped particles with diameter ranging from 3 to 11 nm. The average pore volume was 0.0248 cm 3 /g, and the surface areas of pure and V-doped titania were 62.9 and 66.1 m 2 /g, respectively. The maximum amount of vanadium doped on titania catalyst, as determined using energy dispersive X-ray spectroscopy was 1.7 wt%, and the X-ray diffraction patterns showed the presence of mainly anatase form of titania. The photocatalytic activities of pure and V-doped titania were tested for methylene blue, and the metal uptake was found to increase from 10 mg/g for pure titania to 17 mg/g for V-doped titania. Adsorption isotherms for removal of lead and zinc from aqueous solutions were generated under ultraviolet exposure for 24 h, and the results revealed that the photocatalytic activity was enhanced when titania was doped with vanadium.
Conservation of energy usage is essential in chemical process plants due to the expanded energy users and demands alongside the carry-on hike of energy prices. This study analyzed the performance of energy savings in a heat exchanger network (HEN). It is based on decreasing utility usage while increasing process-to-process heat exchange in HEN using a path combination approach at different heat recovery approach temperatures (HRATs). The approach generates different combined path options for heat shifting from utilities to exchangers in a HEN. In terms of cost targeting, the optimal HRAT in a HEN is determined for each path’s combination option. The study focused on the HEN of crude oil preheat trains. Shifting heat load between utilities implies adding and subtracting loads to and from exchangers in a HEN. Therefore, a minor retrofit to compensate for the heat transfer area is required for some HEN exchangers. The optimum HRAT corresponding to the lowest total cost was determined for each option and ranged between 8 °C and 14 °C. Moreover, two out of five options in HEN with low capital investment and a short payback period were found to be promising.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.