Nile river water is the most important element for vital activities of living beings that used for drinking (Ali, 2012). Dyes are the one of that contamination which comes from many industries manufacturing textile is effect on these living beings. There is about 10-20% dyes used is lost in residual liquors through washing operations, so we have to get rid of these dyes (Wong et el., 2008). Cationic dyes can cause an increase in heart rate, shock, vomiting, cyanosis, jaundice, quadriplegia, Heinz body formation and tissue necrosis in humans (Ahmad and Kumar, 2010) as brilliant green and toluidine blue. Brilliant green (Br.G) is a golden crystal dye with a triphenylmethane family (Allen, 2013) which widely used in a different purpose, such as dermatological agent, veterinary medicine, besides as poultry feed to inhibit spreading of mold (Nandi et el., 2009), but toluidine blue (To.
B) is phenothiazine dye which uses in medicine science, textile industry and biotechnology (Weis et el., 1999; Wainwright, 2003; O’Riordan, 2005; Wainwright, 2005). For trypan blue (Tr.B), it is a carcinogenic azo dye which is used for the preparation of color staining solutions, staining histological sample materials of human origin (Nadaroglu et el., 2017).
It also extensively used in the textile, food and paint industries for dyeing silk, cotton, wool, nylon and also for coloring oil, waxes, varnish and plastics (Lade et el., 2015). Removal of brilliant green, toluidine blue and trypan blue dyes from wastewaters before their release into natural streams and Nile River is very essential for environmental safety. Different methods used for this as coagulation and flocculation (Han et el., 2005), adsorption (Gupta et el., 2003), Biosorption (Sari et el., 2008), electrochemical techniques (Kumar, 2006), but adsorption is the most effective technique because it is very easy, inexpensive and it can treat with concentrated dyes and we can make regeneration for the spent sorbent (Gupta and Ali, 2013).
Many adsorbent used for removing dyes from wastewater, e.g. orange peel (Sivaraj et el.
, 2001), fly ash (Mohan et el., 2002), zeolites (Arma?an and Turan, 2004; Ozdemir et el., 2004) and polyurethane foam.Polyurethane foam (PUF) sorbent has highly surface area due to existence of open porous structures, low cost, stable in acid / base solutions and stable up to 180 ºC (Moawed, 2006; El-Shahat et el.
, 2008). PUF has polar and nonpolar groups in their structure (Baldez et el., 2008; Lee et el., 2009; Moawed and Radwan, 2017), so it can extract different substances. Metal oxide nanoparticles have a great attention lately, especially zinc oxide nanoparticles. ZnONPs get involved in various applications such as gas sensors (Gao et el.
, 2005), solar cells (Hames et el., 2010) and photcatalysts (Kamat et el., 2002). Because of non-toxicity, low cost and high adsorptive properties (Sharma et el., 2017), it is a good choice for removal of dyes. The aim of this paper, polyurethane foam sorbent was modified using thiourea (NH2CSNH2), vanillin (C8H8O3) to form Schiff’s base vanillin thiourea polyurethane foam (SVT-PUF).
The stable powder of [email protected] composite was prepared by condensation of SVT-PUF with ZnO NPs in ethanol. [email protected] was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), thermal analysis (TGA), Brunauer-Emmett-Teller (BET) and FT-IR. Applications of [email protected] for removing of brilliant green, trypan blue and toluidine blue dyes from wastewater at different time, initial concentration, pH and temperature were tested.