Hydrocarbon Mineralization Research Articles

Sulfur-induced interface heterojunctions on Bi2O2CO3 hollow nanosphere for high mineralization of marine polycyclic aromatic hydrocarbons

Sulfur-induced interface heterojunctions on Bi2O2CO3 hollow nanosphere for high mineralization of marine polycyclic aromatic hydrocarbons

Dual-purpose elemental sulfur for capturing and accelerating biodegradation of petroleum hydrocarbons in anaerobic environment

Hydrophobic organic pollutants in aqueous environments are challenging to biodegrade due to limited contact between microorganisms, the pollutants and the electron acceptor, particularly under anaerobic or anoxic conditions. Here, we propose a novel strategy that uses inexpensive, dual-function elemental sulfur (S0) to enhance biodegradation. Using petroleum hydrocarbons as the target pollutants, we demonstrated that hydrophobic and nonpolar S° can concentrate hydrocarbons while simultaneously serving as an electron acceptor to enrich hydrocarbon-degrading bacteria. The permeable reactive barrier filled with S0 effectively removed petroleum hydrocarbons. In addition to rapid adsorption, we discovered, for the first time, that petroleum hydrocarbons underwent efficient biodegradation through the reduction of S0. Specifically, n-alkanes were degraded by 80 % to 90 % and polycyclic aromatic hydrocarbons by 40 % to 95 %. These degradation rates were 17 % to 30 % and 26 % to 43 % higher, respectively, compared to those observed without S0. Consecutive subcultures combined with untargeted metabolomics analysis revealed that bacteria capable of dissimilatory sulfur reduction enhanced the fermentation process. These bacteria provided electrons to the metabolic network, which facilitated the mineralization of petroleum hydrocarbons. Our findings highlight the significant potential of S° for removing hydrophobic organic pollutants in oxygen-free environments, demonstrate the feasibility of integrating adsorption, biodegradation, and electron supply to enhance pollutant removal.

Enhancing biodegradation of aged hydrocarbon-contaminated soils through toluene addition: assessing effects on solid and slurry phase treatments.

The main challenge in treating aged soils highly contaminated with total petroleum hydrocarbons (TPH) is to enhance their bioavailability for microbial degradation. Hydrocarbons in soils undergo chemical changes that make them more resistant to biodegradation. This study investigates toluene's efficacy in enhancing the biodegradation of aged hydrocarbon-contaminated soil containing 292,000mg TPH kg-1 dry soil. Toluene's effect was compared between solid phase (SOP) and slurry phase (SLP) treatments using a microbial consortium isolated from Cyperus laxus rhizosphere. TPH biodegradation and microbial respiration were measured, the latter to estimate the respiratory quotient (RQ, the ratio between moles of carbon dioxide released and moles of oxygen absorbed during respiration). Toluene significantly accelerated TPH biodegradation in both treatments, achieving ~ 30% higher removal than in a non-solvent control, possibly through improved bioavailability of aromatic compounds and other low molecular weight compounds. According to the RQ analysis, toluene enhanced microbial respiratory processes and hydrocarbon catabolism with higher hydrocarbon mineralization (RQ = ~ 0.5) in both SOP and SLP assays. Our results reveal toluene's potential to increase hydrocarbon availability and microbial degradation efficiency in aged contaminated soils; its use in various bioremediation techniques could be of broad applicability across diverse soil types and pollutants.

Unveiling the capacity of bioaugmentation application, in comparison with biochar and rhamnolipid for TPHs degradation in aged hydrocarbons polluted soil

Persistent, aged hydrocarbons in soil hinder remediation, posing a significant environmental threat. While bioremediation offers an environmentally friendly and cost-effective approach, its efficacy for complex contaminants relies on enhancing pollutant bioavailability. This study explores the potential of immobilized bacterial consortia combined with biochar and rhamnolipids to accelerate bioremediation of aged total petroleum hydrocarbon (TPH)-contaminated soil. Previous research indicates that biochar and biosurfactants can increase bioremediation rates, while mixed consortia offer sequential degradation and higher hydrocarbon mineralization. The present investigation aimed to assess whether combining these strategies could further enhance degradation in aged, complex soil matrices. The bioaugmentation (BA) with bacterial consortium increased the TPHs degradation in aged soil (over 20% compared to natural attenuation - NA). However, co-application of BA with biochar and rhamnolipid higher did not show a statistically prominent synergistic effect. While biochar application facilitated the maintenance of hydrocarbon degrading bacterial consortium in soil, the present study did not identify a direct influence in TPHs degradation. The biochar application in contaminated soil contributed to TPHs adsorption. Rhamnolipid alone slightly increased the TPHs biodegradation with NA, while the combined bioaugmentation treatment with rhamnolipid and biochar increased the degradation between 27.5 and 29.8%. These findings encourage further exploration of combining bioaugmentation with amendment, like biochar and rhamnolipid, for remediating diverse environmental matrices contaminated with complex and aged hydrocarbons.

Global Trends in the Use of Biodiesel Fuel

The potential ways for reducing the consumption of hydrocarbon minerals through the use of biofuels are presented, the prospects for increasing the global biodiesel market at an average annual rate of 4.9%, which will amount to about 63 million tons by the end of 2030 are given. The largest producers and consumers of motor biofuel the USA, Brazil, the European Union, Argentina, Indonesia and China are identified. It has been established that the raw materials for producing biofuel from vegetable oils are mainly soybean, canola, jatropha, palm, coconut and castor oils.

EVALUATION OF THE PHYSICO-CHEMICAL AND MINERALOGICAL PROPERTIES OF A CLAY MINERAL DEPOSIT IN OMIALAFARA IN IFON OSE LOCAL GOVERNMENT AREA IN ONDO STATE , NIGERIA

The physico-chemical and mineralogical properties of a clay mineral deposit in Omialafara in Ifon Ose Local Government Area in Ondo State, Nigeria was evaluated using standard methods. The results of the study revealed that the deposit consisted of phyllosilicate minerals- lizardite aluminian, clinochlore feroanB, sepiolite ferrian , neotocite; others were quartz, goethite and evenkite a very rare hydrocarbon mineral. The clay minerals exhibited good swelling property, medium plasticity, shrinkage in excess of recommended range, good thermal resistance and the apparent porosity was within the recommended limit. It had refractoriness below 1200oC. The properties of the clay mineral deposit was a reflection of the combined characteristics of both the clay and non-mineral composition which recommends it for a variety of applications subject to a limiting working temperature of 1200oC. The coloured nature of the clay mineral deposit was accounted for by a combination of the presence of the coloured clay minerals and goethite.

Bioelimination of Phytotoxic Hydrocarbons by Biostimulation and Phytoremediation of Soil Polluted by Waste Motor Oil

Soils contaminated by waste motor oil (WMO) affect their fertility, so it is necessary to recover them by means of an efficient and safe bioremediation technique for agricultural production. The objectives were: (a) to biostimulate the soil impacted by WMO by applying crude fungal extract (CFE) and Cicer arietinum as a green manure (GM), and (b) phytoremediation using Sorghum vulgare with Rhizophagus irregularis and/or Rhizobium etli to reduce the WMO below the maximum value according to NOM-138 SEMARNAT/SS or the naturally detected one. Soil impacted by WMO was biostimulated with CFE and GM and then phytoremediated by S. vulgare with R. irregularis and R. etli. The initial and final concentrations of WMO were analyzed. The phenology of S. vulgare and colonization of S. vulgaris roots by R. irregularis were measured. The results were statistically analyzed by ANOVA/Tukey's HSD test. The WMO in soil that was biostimulated with CFE and GM, after 60 days, was reduced from 34,500 to 2066 ppm, and the mineralization of hydrocarbons from 12 to 27 carbons was detected. Subsequently, phytoremediation with S. vulgare and R. irregularis reduced the WMO to 86.9 ppm after 120 days, which is a concentration that guarantees the restoration of soil fertility for safe agricultural production for human and animal consumption.

The remediation of soil contaminated with oil products via up-to-date methods

Due to the characteristics of the technological processes, the production activity of the enterprises in the oil industry affects the environment more seriously than other spheres. The contaminators of the enterprises of an oil producing complex combine the organic and mineral solutions as well. As the natural process of mineralization of polycyclic aromatic hydrocarbons is long enough, a necessity of the measures towards the acceleration of remediation processes occurs. The paper reviews the positive and negative aspects of the remediation methods applied for the soils contaminated with oil. The mechanical, agro-technical and chemical, as well as other methods of recultivation of the contaminated soils are implemented. The definition of the methods can change depending on the soil content, as well as on the contamination degree. It was specified that the environmental and economic efficiency may be achieved due to the enhancement of self-purification of soil with the employment of a complex of methods.

Features of the self-restoration of the oil-contaminated peat-bog soil – a field study

The features of self-restoration processes of the oligotrophic peat-bog soil disturbed by crude oil pollution were studied. Soil contamination was carried out in field long-term experience. The key soil self-recovery indicators were: (1) the rate of carbon dioxide emission by the soil, which quantitatively characterizes the mineralization of petroleum hydrocarbons by microorganisms; (2) content of petroleum products. The microorganisms of the studied soil were characterized by low resistance to the toxic effects of oil: during the first three years of the experiment, the respiration of oil-contaminated soils was significantly lower than in pure soil. Restoration of microbial respiration to the control level and its further intensive growth occurred after 4-5 years of the experiment only in soils with low oil doses: 0.3 and 0.6 l m-2. In time, this coincided with the maximum rate of oil decomposition, which indicates the microbial nature of its utilization. The respiration of soil with oil high doses (1.8 and 3.0 l m-2) remained significantly lower than in pure soil throughout the entire experiment. At the same time, the amount of oil products in these samples markedly decreased. Oil degradation in these variants could occur due to the activity of anaerobic bacteria or abiotic processes.

Hydrocarbon biodegradation by Proteus and Serratia strains isolated from oil-polluted water in Bonny Community, Niger Delta, Nigeria

Two indigenous hydrocarbon utilizing bacteria strains, designated as TKZ and QGR were isolated in oil rich Niger Delta of Nigeria. Determination of the nucleotide sequence of the gene encoding 16S rRNA allowed TKZ and QGR to be identified as Proteus vulgaris and Serratia marcescens. Hydrocarbon degradation potential of the strains was confirmed on hydrocarbon mineral salts medium (1 %, v/v) at 37 °C. Assessment of oil degradation capability of the isolates was monitored using gas chromatographic analysis (GC). The ability of the strains to utilize benzene, diesel, kerosene, and naphthalene was also studied. The results show maximal increase in optical densities at 540 nm and total viable counts was proportional with decrease in pH of the culture media. Percentage degradation in the culture medium showed that the two isolates exhibited biodegradation efficiency above 90 % for kerosene. The two bacterial strains also possess a plasmid of about 9.1 kb size which is suspected to influence the bacterium’s hydrocarbon degradation potential.

Bio-Fenton-Assisted Biological Process for Efficient Mineralization of Polycyclic Aromatic Hydrocarbons from the Environment

The intensive production of fossil fuels has led to serious polycyclic aromatic hydrocarbon (PAH) contamination in water and soil environments (as PAHs are typical types of emerging contaminants). Bio-Fenton, an alternative to Fenton oxidation, which generates hydrogen peroxide at a nearly neutral pH condition, could ideally work as a pretreatment to recalcitrant organics, which could be combined with the subsequent biological treatment without any need for pH adjustment. The present study investigated the performance of a Bio-Fenton-assisted biological process for mineralization of three typical types of PAHs. The hydrogen peroxide production, PAH removal, overall organic mineralization, and microbial community structure were comprehensively studied. The results showed that the combined process could achieve efficient chemical oxygen demand (COD) removal (88.1%) of mixed PAHs as compared to activated sludge (33.1%), where individual PAH removal efficiencies of 99.6%, 83.8%, and 91.3% were observed for naphthalene (NAP), anthracene (ANT), and pyrene (PYR), respectively, with the combined process.

‘Hartite’ renamed branchite

AbstractHistorical samples of branchite, described by the Tuscan naturalist Paolo Savi (1798–1871) at the end of the 1830s, were re-examined through single-crystal X-ray diffraction, showing their identity with hartite, C20H34, a hydrocarbon mineral described by Haidinger in 1841. The refined unit-cell parameters are a = 11.4116(7), b = 20.9688(12), c = 7.4100(4) Å, α = 93.947(2), β = 100.734(2), γ = 80.524(2)°, V = 1716.99(17) Å3 and Z = 4; space group P1. The crystal structure was solved and refined up to R1 = 0.0424 for 13512 reflections with Fo > 4σ(Fo) and 1265 refined parameters. As the name ‘branchite’ has priority over ‘hartite’, the reinstatement of the former name and the discreditation of the latter were approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA–CNMNC). Branchite is one of only eleven minerals formed by C and H listed in the official IMA List of Minerals. The type locality of branchite is the Botro di Lavajano, Monte Vaso, Chianni, Pisa, Tuscany, Italy. Neotype material is kept in the Natural History Museum of the Pisa University under catalogue number 14426.

Comparative Analysis of Palm Oil and Hydrocarbon Mineral Oil for Power Transformer Operation

The erstwhile transformer oil material, for all these periods of more than two centuries, has been championing liquid dielectrics, for machines’ cooling and insulation purposes. However, its use has detrimental and attendant consequences on global terrestrial and aquatic habitats, industries and global warming. Palm oil (Elaise Guinensis Eg; and/or Elaise Oleifera Eo) is presently posing a great challenge to liquid hydrocarbon in the operation of transformers. Despite the ease in availability of mineral oil today, especially for oil producing nations, this paper aims at unveiling its several underscores and analyses of the viscosity, flash point, density, neutralisation (acidic value) number, electrical resistivity, and breakdown voltage (BDV) results of the respective mineral and palm oil samples. Palm oil’s test results values of approximately, 244OC, 55kV and 0.004 mgkOH/gm of oil, was recorded, respectively for the flash point, breakdown voltage (BDV) and acid neutralisation index, as compared with corresponding mineral oil’s values of 142OC, 59kV and 0.004 mgkOH/gm. The results obtained favoured the use of palm oil than the mineral oil for transformer’s operation.

Features of the geological structure and oil and gas content of the shelves of the Far Eastern Seas

Russian shelf is one of the most important areas for hydrocarbon forecast and mineral resources development. The main features of the geological structure of the shelves of the Far Eastern seas are discussed in the paper. The most promising basins on the Okhotsk shelf are located around Sakhalin island where the majority of the hydrocarbon fields have been discovered. The Bering and the Japan shelf has not been sufficiently studied by now but nevertheless has high oil and gas potential. The main focus is made on the geological and geophysical data, licensing, lithological and stratigraphic structure, seismic interpretation, oil and gas fields distribution. The structural-tectonic zoning of the entire Far Eastern region has been done in order to identify zones of deep troughs with thick sedimentary cover to predict the sources of hydrocarbon generation.

Quantitative relationship between the resistivity distribution of the by-product plume and the hydrocarbon degradation in an aged hydrocarbon contaminated site

During the investigation of aged hydrocarbon contaminated sites using electrical resistivity tomography (ERT), the low-resistivity anomalies in the detection profile have been widely considered to be caused by the hydrocarbon degradation by-products. However, these low-resistivity anomalies are a comprehensive reflection of the formation’s electrical characteristics. In this study, we used ERT and geochemical methods to investigate a hydrocarbon-contaminated site that has been abandoned for more than 30 years. There are several obvious low resistivity anomalies in the site, which are related to hydrocarbon mineralization. Based on the law of Waxman and Smits, a petrophysical relationship formula suitable for this specific site was fitted, and the true resistivity after inversion was input into the formula to calculate the pore water resistivity. The electrolytic conduction contribution of the pore water was isolated, and the distribution of the by-product plume was determined based on the electrolytic conduction contribution of the pore water. Based on mineralogical identification and geochemical data analysis, the biogeochemical model of hydrocarbon mineralization was clarified. The degradation by-products (Fe2+ and H+) are the controlling factors that lead to changes in the groundwater resistivity. Based on electrochemical experiments and titration analysis experiments, the quantitative relationship between the low resistivity anomalies of the pore water and the degradation by-products (Fe2+ and H+) was established, and the biodegradation model was used to calculate the hydrocarbon degradation corresponding to the by-product plume. The results show that the hydrocarbon degradation corresponding to the by-product plume determined from the ERT detection results in the selected study area is approximately 2.8% of the total hydrocarbon content. Although this is a rough estimate based on a small amount of discrete geochemical data and ERT detection results, it improves our understanding of the natural attenuation state of hydrocarbon-contaminated sites and provides convincing data to support future estimations of the site's natural attenuation time.

Nutrient removal and microbial community structure in an artificial-natural coupled wetland system

An artificial-natural coupled wetland was constructed at an estuary between an upstream river and a downstream lake to transport river water and reduce nutrient input load into a grass-type shallow lake. The removal efficiencies of chemical oxygen demand (COD) and total nitrogen (TN) were as high as 43 % and 83 %, respectively. Their concentrations were reduced to 30.98 mg/L and 0.79 mg/L, respectively. The lotus pond had high microbial diversity and was key for water purification. It contributed 19 % and 49 % of the removal efficiencies of COD and TN, respectively. Most of the dominant microorganism in wetland were related to the transformation of C and N. Bacterial phyla containing phototrophic members accounted for three-quarters of the microorganisms and significantly contributed to bioactivity. Phylum Proteobacteria, the most abundant microbial species, were involved in both N and C cycling because of the metabolic versatility. The denitrification of the wetland depended on the classes Gammaproteobacteria, Deltaproteobacteria, Bacteroidia and Anaerolineae. Bacteria of the phyla Chloroflexi, Actinobacteria, Firmicutes, Spirochaetes, Bacteroidetes and class Alphaproteobacteria contributed to hydrocarbon mineralization and carbonate decomposition to promote C cycling. Therefore, this study provides insights to develop effective methods for reducing the risks of lake eutrophication and protecting the water ecological health.

Atmospheric Solids Analysis Probe (ASAP) and Atmospheric Pressure Gas Chromatography (APGC) coupled to Quadrupole Time of Flight Mass Spectrometry (QTOF-MS) as alternative techniques to trace aromatic markers of mineral oils in food packaging

The aim of this work was to select and identify the best markers of aromatic hydrocarbon mineral oil (MOAH) in food packaging. For this purpose, a series of mineral oils was initially analysed. Polycyclic Aromatic Hydrocarbons (PAHs) and the alkylated isomers of Methylnaphthalene (MNS), Diisopropylnaphtalene (DIPNs), Dibenzothiophenes (DBTS), Methyldibenzothiophene (MDBTs), Dimethyldibenzothiophenes (DMDBTs) and Benzonaphthiophenes (BNTS) were then explored. Their presence was confirmed by direct analysis of several mineral oils by Atmospheric Solids Analysis Probe Quadrupole-Time of Flight Mass Spectrometry (ASAP-QTOF-MS). Atmospheric Pressure Gas Chromatography Quadrupole-Time of Flight Mass Spectrometry (APGC-QTOF-MS) was used to confirm the markers in different samples of oils, recycled PET (rPET), recycled cardboard and packaging of couscous and semolina to confirm the contamination. 27 markers were found in the mineral oil samples, 22 of them in rPET, 8 in recycled board and no MOAH were found in packaging of couscous and semolina.

New Frontiers of Anaerobic Hydrocarbon Biodegradation in the Multi-Omics Era.

The accumulation of petroleum hydrocarbons in the environment substantially endangers terrestrial and aquatic ecosystems. Many microbial strains have been recognized to utilize aliphatic and aromatic hydrocarbons under aerobic conditions. Nevertheless, most of these pollutants are transferred by natural processes, including rain, into the underground anaerobic zones where their degradation is much more problematic. In oxic zones, anaerobic microenvironments can be formed as a consequence of the intensive respiratory activities of (facultative) aerobic microbes. Even though aerobic bioremediation has been well-characterized over the past few decades, ample research is yet to be done in the field of anaerobic hydrocarbon biodegradation. With the emergence of high-throughput techniques, known as omics (e.g., genomics and metagenomics), the individual biodegraders, hydrocarbon-degrading microbial communities and metabolic pathways, interactions can be described at a contaminated site. Omics approaches provide the opportunity to examine single microorganisms or microbial communities at the system level and elucidate the metabolic networks, interspecies interactions during hydrocarbon mineralization. Metatranscriptomics and metaproteomics, for example, can shed light on the active genes and proteins and functional importance of the less abundant species. Moreover, novel unculturable hydrocarbon-degrading strains and enzymes can be discovered and fit into the metabolic networks of the community. Our objective is to review the anaerobic hydrocarbon biodegradation processes, the most important hydrocarbon degraders and their diverse metabolic pathways, including the use of various terminal electron acceptors and various electron transfer processes. The review primarily focuses on the achievements obtained by the current high-throughput (multi-omics) techniques which opened new perspectives in understanding the processes at the system level including the metabolic routes of individual strains, metabolic/electric interaction of the members of microbial communities. Based on the multi-omics techniques, novel metabolic blocks can be designed and used for the construction of microbial strains/consortia for efficient removal of hydrocarbons in anaerobic zones.

Dynamics of hydrocarbon mineralization characterized by isotopic analysis at a jet-fuel-contaminated site in subtropical climate

Release of benzene, toluene, ethylbenzene, and xylene (BTEX) as components of the light non-aqueous phase liquids (LNAPL) contaminates soil and groundwater. Assessing the mechanisms of degradation and mineralization of BTEX in groundwater helps understand the migration of the dissolved plume, enabling the reduction of risks to humans. Here, we studied the fate of ethylbezene, m,p-xylenes and o-xylenes and the accompanying formation of methane in a Cenozoic lateritic aquifer in Brazil by compound-specific carbon stable isotope analysis (CSIA), to gain insights into the complex dynamics of release and biodegradation of BTEX in the LNAPL source zone. The enrichment of ∂13C in aromatic compounds dissolved in groundwater compared to the corresponding compounds in LNAPL indicate that CSIA can provide valuable information regarding biodegradation. The isotopic analysis of methane provides direct indication of oxidation mediated by aquifer oxygenation. The ∂13C-CO2 values indicate methanogenesis prevailing at the border and aerobic biodegradation in the center of the LNAPL source zone. Importantly, the isotopic results allowed major improvements in the previously developed conceptual model, supporting the existence of oxic and anoxic environments within the LNAPL source zone.

Microbial Degradation of Different Hydrocarbon Fuels with Mycoremediation of Volatiles.

Naturally occurring microorganisms in soil matrices play a significant role in overall hydrocarbon contaminant removal. Bacterial and fungal degradation processes are major contributors to aerobic remediation of surface contaminants. This study investigated degradation of conventional diesel, heating diesel fuel, synthetic diesel (Syntroleum), fish biodiesel and a 20% biodiesel/diesel blend by naturally present microbial communities in laboratory microcosms under favorable environmental conditions. Visible fungal remediation was observed with Syntroleum and fish biodiesel contaminated samples, which also showed the highest total hydrocarbon mineralization (>48%) during the first 28 days of the experiment. Heating diesel and conventional diesel fuels showed the lowest total hydrocarbon mineralization with 18–23% under favorable conditions. In concurrent experiments with growth of fungi suspended on a grid in the air space above a specific fuel with little or no soil, fungi were able to survive and grow solely on volatile hydrocarbon compounds as a carbon source. These setups involved negligible bacterial degradation for all five investigated fuel types. Fungal species able to grow on specific hydrocarbon substrates were identified as belonging to the genera of Giberella, Mortierella, Fusarium, Trichoderma, and Penicillium.