Introducing Nonylphenol and Its Removal Methods from Wastewater

Nonylphenol (NP) is important as a toxic xenobiotic compound, carcinogenic and endocrine disrupter by interfering with the hormonal system of organisms. It originates from the degradation of Nonylphenol ethoxylates (nonionic surfactants). Due to its physicochemical characteristics, such as low solubility and high hydrophobicity, nonylphenol accumulates in sewage sludge, effluents from sewage treatment, river water sediments, soil and surface water. Since NP is the most toxic and abundant alkylphenols, the use and production of such compounds have been banned in EU member countries and strictly monitored in many other countries such as Canada and Japan. Due to its toxicity and bioaccumulation effects on organism especially aquatic life, making rules and regulations along with analysis and measurement of NP are important. Consequently, there is a concern within some industries about the possibility of future regulations that may impose the removal or reduction of micro pollutants by providing alternatives with lower toxicity and stability, cost and suitable efficiency. The significance of upgrading sewage treatment processes with advanced treatment technologies for removal of these contaminants in range of the standards is considered. In this regard, several methods with high efficiency have been proposed for treatment wastewater with NP compounds such as adsorption by Nano-adsorbents and Nano-particles, biosorption, advanced oxidation, photodegradation, etc., as well as the methods for reduction of NP from sludge such as composting and aerobic stabilization.