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Application of Mineral Sorbents for Removal of Petroleum Substances: a Review

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Application of Mineral Sorbents for Removal of Petroleum Substances: a Review minerals Review Application of Mineral Sorbents for Removal of Petroleum Substances: A Review Lidia Bandura 1,*, Agnieszka Woszuk 2, Dorota Kołody ´nska 3 and Wojciech Franus 1 1 Department of Geotechnical Science, Faculty of Civil Engineering and Architecture, Lublin University of Technology, Nadbystrzycka 40, 20-618 Lublin, Poland; [email protected] 2 Department of Roads and Bridges, Faculty of Civil Engineering and Architecture, Lublin University of Technology, Nadbystrzycka 40, 20-618 Lublin, Poland; [email protected] 3 Department of Inorganic Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, Maria Curie-Skłodowska Sq.2, 20-031 Lublin, Poland; [email protected] * Correspondence: [email protected]; Tel.: +48-509-381-660 Academic Editor: Annalisa Martucci Received: 15 December 2016; Accepted: 4 March 2017; Published: 8 March 2017 Abstract: Environmental pollution with petroleum products has become a major problem worldwide, and is a consequence of industrial growth. The development of sustainable methods for the removal of petroleum substances and their derivatives from aquatic and terrestrial environments and from air has therefore become extremely important today. Advanced technologies and materials dedicated to this purpose are relatively expensive; sorption methods involving mineral sorbents are therefore popular and are widely described in the scientific literature. Mineral materials are easily available, low-cost, universal adsorbents and have a number of properties that make them suitable for the removal of petroleum substances. This review describes recent works on the use of natural, synthetic and modified mineral adsorbents for the removal of petroleum substances and their derivatives from roads, water and air. Keywords: petroleum substances; oils; BTEX; sorption; removal; mineral adsorbents 1. Introduction In the modern context of advanced and developing industrialization, petroleum products and their derivatives constitute one of the major sources of environmental pollution. During the extraction, transport, distribution and storage of crude oil and its products, these may be released into the environment in an uncontrolled manner, causing pollution of the atmosphere, lithosphere, hydrosphere and biosphere [1–6]. Due to the extent of impact and the adverse effect of oil derivatives on both the inanimate and animate environment, and the limits imposed on their emissions and permissible concentrations in soils and water, the search for effective methods and new materials for the removal of such substances from contaminated sites is extremely important. Environmental pollution caused by petroleum substances can be divided into four groups, according to location: • atmospheric pollution caused by the evaporation of volatile components of petroleum products; • pollution of soils; • pollution of aquatic systems; • environmental pollution caused by land-based spills of petroleum products. For each of these groups, it is important to choose appropriate methods for the removal of undesirable organic substances in the most efficient way. Minerals 2017, 7, 37; doi:10.3390/min7030037 www.mdpi.com/journal/minerals Minerals 2017, 7, 37 2 of 25 A number of mechanical, biological, chemical and adsorption methods are currently used to Minerals 2017, 7, 37 2 of 25 remove oil spills from water media and paved roads, and to remove volatile hydrocarbons (Figure 1) [7–14]. ASolutions number of applied mechanical, to volatile biological, organic chemical compounds and adsorption are primarily methods aimed are at currentlymonitoring used and toreducing remove oiltheir spills emissions from waterusing destructive media and methods paved roads, and recovery and to techniques remove volatile [15]. The hydrocarbons most popular (Figureof these1) [ 7are–14 adsorption]. techniques involving various kinds of adsorbents. Methods for the removal of petroleum substances adsorption mechanical chemical biological the use of dams and mineral sorbents burning bioremediation floating barriers natural organic mechanical biostimulation of native the use of dispersants sorbents collecting(skimmers) microorganisms bioaugmentation - synthetic solidification introducing of organic/polymers microorganisms FigureFigure 1. Methods1. Methods used used for for the the petroleum petroleum substance substance removal. removal. SolutionsUsually, applied during to rescue volatile operations organic compounds on waters, more are primarily than one aimed method at monitoringis applied. Comprehensive and reducing theirrescue emissions operations using are destructive aimed at methodsefficient removal and recovery of oil techniquesspills from [ 15the]. water The most surface popular and the of these coastal arezones adsorption and at techniques preventing involving further migration various kinds of thes ofe adsorbents. contaminants. The different cleanup techniques areUsually, discussed during as follows rescue [16]: operations on waters, more than one method is applied. Comprehensive rescue operationsIn situ burning are aimed is performed at efficient as soon removal as possible of oil spills after fromthe spill, the waterbefore surface the oil stain andthe will coastal begin to zonesevaporate and at preventingvolatile components further migration and disperse. of these Usually contaminants., burning The is differentused at large cleanup water techniques surfaces are(seas discussedand oceans) as follows but also [16 on]: land. To perform the burning process effectively the oil spill should be fresh, containIn situ volatile burning components, is performed and as the soon thickness as possible of the after oil layer the spill, should before be at the least oil stain2–3 mm. will In begin addition, to evaporatethe water volatile surface components cannot be and rough, disperse. and Usually,the location burning of burning is used atshould largewater be safely surfaces away (seas from and the oceans)residential but also areas, on land. flammable To perform objects, the burningthe coasts, process living effectively organisms the habi oiltats, spill etc. should Such be conditions fresh, contain occur volatilein Arctic components, areas, since and low the thicknesstemperatures of the limit oil layer the movement should be at of least water, 2–3 mm.the dispersion In addition, ofthe stains, water and surfaceevaporation cannot of be volatile rough, components and the location [17]. The of burning main ad shouldvantages be of safely in situ away burning from are: the low residential costs, high areas,removal flammable efficiency objects, in a the relatively coasts, livingshort time organisms (100–300 habitats, tons per etc. hour). Such conditionsA major drawbacks occur in Arctic are the areas,atmospheric since low temperaturesemissions of limit toxic the movement combustion of water, products the dispersion (CO, ofSO stains,2, polycyclic and evaporation aromatic ofhydrocarbons—PAHs) volatile components [17 and]. The the mainthreat advantagesof the environment. of in situ burning are: low costs, high removal efficiencyDispersive in a relatively method short involves time (100–300 the removal tons per of hour).residual A majoroil film drawbacks with the areuse the of atmospheric surface-active agents (surfactants). Due to an amphiphilic character, they reduce the interfacial tension between oil emissions of toxic combustion products (CO, SO2, polycyclic aromatic hydrocarbons—PAHs) and the threatand ofwater the environment. causing dispersion and oil dilution. Thus, further process of natural biodegradation of petroleumDispersive compounds method involves is facilitated the removal and ofthe residual subsequent oil film removal with the by use mechanical, of surface-active biological agents or (surfactants).sorption means Due is to easier an amphiphilic and more effective character, [18,19]. they reduce Due to the toxicity interfacial the usage tension of dispersants between oil in and some watercountries causing is dispersionlimited (UK, and USA). oil dilution. Dispersion Thus, method further processis efficient of natural in the removal biodegradation of large of scale petroleum oil spills compounds(it is possible is facilitated to spray and dispersants the subsequent from a removal helicopter). by mechanical, They are not biological recommended or sorption in meansthe case is of easier and more effective [18,19]. Due to toxicity the usage of dispersants in some countries is limited (UK, USA). Dispersion method is efficient in the removal of large scale oil spills (it is possible to spray Minerals 2017, 7, 37 3 of 25 dispersants from a helicopter). They are not recommended in the case of heavy, high viscosity oils or in cold, calm water. Surfactants are also used in cleaning soils from petroleum derivatives [20]. Solidifiers are generally dry, granular, hydrophobic organic polymers that react with oil to form a monolithic solid that floats on water [21,22]. The formed solid can be easily removed from the water surface. The effectiveness of solidification depends on the ambient temperature, the type and chemical composition of the oil (solidifier can bind only one type of petroleum substance) which may limit their application. Furthermore, it is recommended to use large amounts of the material (16%–200% by weight) in relation to the weight of oil spill [23]. Few recent studies in this area indicate that solidification is possible only to local impurities of small range. Mixing solidifiers with the oil is difficult, solidifiers may exhibit toxic properties,
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