Research Of Diamondiod Compounds Application To Oil Spill Identification

In the recent years，with the development of economic and social of global，human demand of petroleum resources was increasing. With the rapid development ofoil exploitation and petroleum transportation, oil spill occurs often and make seriousdamage for marine ecology, marine natural resources and coastal economydependencing on Ocean.In the event of oil spills,unambiguous and timely oil spillidentification and finding the source is extremely important for settling questions ofenvironmental impact and legal liability.When oils enter the marine environment, the fate and behavior of spilled oils inthe environment depend on weathering process including evaporation,dissolution,Dispersion, Emulsification photo oxidation, microbial degradation and so on. Theseprocesses cause the lack of chemical composition and to a certain extent change the oilspill inherent chemical fingerprints characteristics that makes accuracy and efficiencyof oil spill identification decrease.so it is particularly importan for Establishing a set ofcomplete and accurate oil spill identification system.Oils from different product places or after different refining processes havedifferent distinct characters. The key of oil spill identification is to find the indexrepresenting the oil intrinsic features and described by analytical instruments. Atpresent the oil spill indexs include normal alkanes index, aromatic index and biologicalmarkers index.There is a question that these indexs are usually molecular weightlarger compounds With a high concentration exists in Heavy oilsBut with a low concentration exists in lighter oils.It is difficult to identify thelighter oil spill.So that Looking for compounds as oil spill identification indexrepresenting the intrinsic features and having good Weathering stability is the key inOil spill. Identification field. Diamondoids are thought to be formed from rearrangements of organic precursorsincluding multiring terpenes under thermal stress with strong Lewis acids acting ascatalysts during oil generation. In recent years,oil spill identify workers pay moreattention for diamondoids as result of its very strong resistance to antibioticsdegradation ability and degradation ability. The main studies and results of this paperare outlined as follows:(1) summarized the oil spill pollution status at home and abroad at this stage andbriefly described the weathering processes of oil spill after entering environment;Introduced the investigative status of fingerprint identification technology for spilledoil. Expatiated the process from finding to application and the reaserch of thesecompounds for forensic oil spill investigations. On this basis, the innovations andresearch content of this paper was put forward.(2) By gas chromatography mass spectrometryand selected ion model themeothed of analysis of diamondoids was established Diamondoids fingerprinting of6crude oils from different offshore oil platform were analysed,main conclusions are asfollows:The concentration of adamantanes is higher than diamantanes;Crude oils fromdifferent offshore oil platform but the same block exhibit very similar diamondiodsignatures,in contrast,oils from different sources have different signatures of both theconcentrations and relative distribution patterns of diamondoid compounds.(3) Redefined18diagnosis ratios of diamondoids, diagnostic power (DP) isapplied to investigate Preliminary the source-sensitivity of diagnostic ratios.Based on18diagnosis18different crude oil were assessmented by principal componentanalysis.a lot of crude oils which have the certain difference were fast identificatedthrough this method(4) Two crude oils from Bohai Sea were natural weathered in long-term.Theresults show that the distribution patterns of diamondoid compounds in crude oil hadgreat change after100days natural weathering: Diamantanes have strongerweathering-resistant capabilities than adamantanes. According to the "Student’s t"statistics,the ratios of A6、A8、A12、A16、A17and A18had no apparent changes whichcould indicate the source of the samples during20days weathering. Diamantanesratios of A17、A18are essentially unaltered after100days natural weathering whichcould indicate the source of the samples during natural long-term weathering.(5)One crude oil werer experimented in iverbeds modeling of biologicaldegradation in two different nutrient conditions. The results show that diamantanes ratios of A16、 A17、 A18are essentially unaltered after21days degradation;Adamantanes have weaker weathering-resistant capabilities and were could indicateselectively the source of the samples duringl short-term weathering.In short, this paper revealed the distribution characteristics of diamondoidscompunds in crud oils.it revealed changes of diamondoids compunds in the crudeoilunder different natural weathering conditions and in iverbeds modeling of biologicaldegradation, and the stable diamondoid diagnostic ratios will enrich the indicatorparameters for oil spill identification to improve oil spill identification system.