Synthesis And Characterization Of Zn-and Cu-based Nanocompositcs From Petroleum Refinery Wastewater

With the development of nanotechnology, some nanomaterials such as oxides，sulfides and composites oxide and sulfide with special morphology have extensivelyapplication in the field of physics and chemistry. Among various semiconductors,ZnO/ZnS and CuO/CuS nanocomposits have received a widespread attention due totheir photocatalysts. As a kind of organic wastewater with high concentrationpetroleum refinery wastewater often contain numerous inorganic salts, sulfide,surfactant, thiophene, high concentrations of alkalinity (pH is about14). Thewastewater needs careful treatment before discharge. However, the direct use ofpetroleum refinery wastewater to synthesis semiconductor is seldom reported inrecent years. Due to the unique materials contained in the wastewater, we used asimple method to synthesis ZnO/ZnS and CuO/CuS nanocomposits.In this paper, petroleum refinery wastewater provide sulfur, alkali and surfactants,we synthesized ZnO/ZnS nanoparticles by hydrolysis and co-precipitation method; byhydrothermal methods we synthesized ZnO/ZnS and CuO/CuS nanocomposits,respectively. And we also considered the effect on the synthesis of ZnO/ZnS andCuO/CuS nanocomposits under different pH conditions. We tested the photocatalyticproperty to methyl orange (MO) aqueous of products. The results can be summarizedas follows:1. The ZnO/ZnS nanoparticles were directly synthesized by mixingZn(CH3COO)2·2H2O solution with petroleum refinery wastewater at90oC andambient pressure. The TEM images illustrated that the ZnO/ZnS nanoparticles with anaverage crystal sizes of less than10nm. The optical properties were investigated byPL. And the PL signal peak can be observed at~365nm. The ZnO/ZnS nanoparticleshave a photocatalytic activity of degrading MO aqueous solution under100WUV-light. The MO solution was degraded in120min. This work provides a novel route for the synthesis of quantum dot-sized photocatalysts from wastewater for thedegradation of dye wastewater.2. The ZnO/ZnS nanocomposits with photocatalytic properties were fabricated via afacile hydrothermal method. The ZnO/ZnS nanocomposits have a photocatalyticactivity of degrading MO aqueous solution under100W UV-light. The MO solutionwas degraded in260min. The pH is one of the important factors influencing themorphology and properties of products. The goal of this work is to synthesis ZnO/ZnSnanocomposits in wastewater with pH values ranging from6to12. With the increaseof the pH, the morphology of the product has also been changed. A layer of thin filmgradually grew on the short spindle type rod. At pH12, the short spindle type rod isload in the thin film.3. The CuO/CuS nanoparticles with photocatalytic properties were fabricated via afacile hydrothermal method. The XRD results showed that the products were CuOand CuS. The CuO/CuS nanoparticles have a photocatalytic activity of degrading MOaqueous solution under100W UV-light. The MO solution was degraded in180min.The pH is one of the important factors influencing the morphology and properties ofproducts. The goal of this work is to synthesis CuO/CuS nanoparticles in wastewaterwith pH values ranging from3to14. The TEM and SEM results indicated that withthe increase of the pH, the reunion phenomenon of products is reduced.