TY - JOUR ID - 89740 TI - Review on Naphthenic Acids: An Important Environmental Pollutants Caused by Oil Extraction and Industries JO - Pollution JA - POLL LA - en SN - 2383-451X AU - Sotoudeh, Yaser AU - Niksokhan, Mohammad Hossein AU - Karbassi, Abdolreza AU - Sarafrazi, Mohammad Reza AD - PhD Candidate, Department of Environmental Engineering, University of Tehran, Iran AD - Department of Environmental Engineering, Faculty of Environment, University of Tehran, Iran AD - Connoisseur in charge of HSE petrochemical projects of National Iranian Petrochemical Company, Iran Y1 - 2023 PY - 2023 VL - 9 IS - 1 SP - 254 EP - 270 KW - Naphthenic acids KW - Crude Oil KW - Pollutant KW - environment KW - Petroleum DO - 10.22059/poll.2022.344876.1532 N2 - Naphthenic acids are a group of polar organic carboxylic acids that are present in crude oil naturally. They are cycloaliphatic carboxylic acids which have 10 to 16 carbons, which gained importance since the early twentieth century because of corrosion in oil refineries. Moreover, they are the most important environmental pollutants caused by oil extraction from oil sand reserves. Heavy crude oils which have high concentration of naphthenic acids are usually considered as poor-quality oil and sold at a lower price. Often, the high concentration of naphthenic acids in crude oil reduces the life of the equipment which are used in the exploration and refining process because of corrosion. Hence, researchers are increasingly interested in the chemical properties of naphthenic acids and the acidic components of the crude oils. The most popular methods for the identification and analysis of naphthenic acids are liquid and gas chromatography (GC), liquid-liquid extraction, Fourier transform infrared spectroscopy (FTIR), and solid-phase extraction (SPE). Naphthenic acids are the most important environmental pollutants caused by oil extraction from oil sand reserves. Previous studies have revealed that naphthenic acids can be absorbed by fish, but their distribution in different tissues of fish has not been specified. Experimental samples showed the highest toxicity to fish, while there was less toxicity to invertebrates and algae. Moreover, naphthenates have various industrial utilizations; they are used in synthetic detergents, corrosion inhibitors, lubricants, fuel and oil additives, wood preservatives, insecticides, fungicides, pesticides, wetting agents, napalm thickening agents, and oil desiccants that are utilized in painting and treating wood surfaces. UR - https://jpoll.ut.ac.ir/article_89740.html L1 - https://jpoll.ut.ac.ir/article_89740_4ed69fc224cd94f916330e41447c3984.pdf ER -