Monika J. Fabiańska

Relationship between petrographic and geochemical characterisation of selected South African coals

Abstract Fifteen samples of South African coals from the Waterberg, Soutpansberg (Northern Province) and Main Karoo (Mpulanga and KwaZulu-Natal) provinces were investigated by petrographic and geochemical methods. The aim of this work was to establish the relationship between these two methods for evaluation of coal maturity in the case of South African coals. The petrographic analyses included maceral and microlithotype evaluation by routine quantitative methods as well as random reflectance measurements. Maceral analysis included identification of vitrinite, liptinite and inertinite groups. The same samples were used for microlithotype analysis. Vitrite, liptite, inertite, clarite, durite,vitroinertite, duroclarite, clarodurite and carbominerite were identified. To assess the facies trends, liptinite-poor and liptinite-rich durite and clarodurite were counted separately. Sporoclarite and cutinodetrite were also treated independently. Both maceral and microlithotype analyses were performed to confirm the geochemical and petrographic compatibility in interpretation of the primary organic material which was deposited in the biochemical stage of coal formation. The reflectance measurements were carried out in incident light using a Zeiss Universal microscope. The 546 nm interference filter was applied. Distributions of aliphatic and aromatic hydrocarbons present in coal extracts were analysed by gas chromatography-mass spectrometry (GC-MS) for assessment of both source/environment of deposition and coal thermal maturity. Normal alkane distribution shows odd-over-even carbon number predominance in the case of coals in the range of 0.63–0.80% vitrinite reflectance. Several groups of compounds related to conifer resin were identified indicating predominant source of organic matter of the coals, for example tetracyclic diterpanes, retene and simonellite. The coal rank was assessed by 13 thermal maturity parameters based on isomerisation reactions of sterane and triterpane diastereomers together with ratios and indices of aromatic hydrocarbons and methyldibenzothiophenes based on different thermal resistance of their α- and β-alkyl isomers. The correlation of reflectance (Rrv%) with two sterane diasteromer parameters: C29αββ/(ααα+αββ), C29ααα20S/(20S+20R) and aromatic hydrocarbon parameters of thermal maturity such as: MDR (Methydibenzothiophene ratio), MPI-1 (MethylPhenanthrene Index-1) revealed good agreement. Lower correlation coefficients were obtained for TMR-2 (Trimethylnaphthalene ratio), TeNR (Tetramethylnaphthalene ratio) and DMPR (Dimethylphenenthrene ratio) with respect to Rrv%. Other correlations of biomarker and aromatic hydrocarbon parameters with Rrv% were poor.

Geochemical markers of soil anthropogenic contaminants in polar scientific stations nearby (Antarctica, King George Island).

The organic contamination of Antarctic soils and terrestrial sediments from nearby of five polar scientific stations on King George Island (Antarctica) was investigated. Gas chromatography-mass spectrometry (GC-MS) was applied to find composition of dichloromethane extracts of soil and terrestrial sediments. The presence of geochemical markers, such as n-alkanes, steranes, pentacyclic triterpenoids, and alkyl PAHs, their distribution types, and values of their ratios indicates the predominating source of organic fossil fuels and products of their refining rather than from the natural Antarctic environment. Fossil fuel-originated compounds well survived in conditions of Antarctic climate over long times thus enabling to characterize geochemical features of source fossil fuel identified as petroleum expelled from kerogen II of algal/bacterial origins deposited in sub-oxic conditions and being in the middle of catagenesis. Both microbial activity and water leaching play an important role in degradation of terrestrial oil spills in the Antarctica climate, and petroleum alteration occurs lowly over long periods of time. Synthetic anthropogenic compounds found in terrestrial Antarctica sediments included diisopropylnaphthalenes, products of their sulfonates degradation in paper combustion, and organophosporus compounds used as retardants and plasticizers.

Microbial alteration of organic matter of humic coal during biological desulphurisation

Abstract The biodegrading influence of biological desulphurisation on bituminous coal and its density fractions was investigated using gas chromatography–mass spectrometry for organic matter alteration and atomic absorption for the assessment of changes in several trace element concentrations. Changes in extract group composition were assessed by comparing the contents of aliphatic, aromatic and polar compounds separated by preparative thin layer chromatography. Aliphatic compounds show extensive alteration due to biodegradation, mainly removal of n-alkanes and lighter acyclic isoprenoids from extracts. The sterane distribution was strongly affected while hopane/moretane distributions show minor changes. Aromatic hydrocarbons were less influenced but some changes were found. It can be assumed that the degree of biodegradation of density fractions increases with increasing concentration of mineral matter since density fractions with lower mineral concentration show smaller changes as a result of biodegradation than those with higher content of minerals. Reduction of concentrations of the following trace elements occurred: beryllium, chromium, zinc, gallium, cadmium, cobalt, lithium, manganese, copper, molybdenum, nickel, lead, and vanadium. The content decrease of an element is not influenced by its geochemical properties. An equally important factor seems to be bonding to organic and inorganic coal substances.

Plant occurrence on burning coal waste – a case study from the Katowice-Wełnowiec dump, Poland

Abstract Coal-waste dumps superimposed on former rubbish dump frequently undergo selfheating and selfignition of organic matter dispersed in the waste. The special conditions for plant growth generated as a result have been investigated since 2008 on the municipal dump reclaimed with coal wastes in Katowice-Wełnowiec, Poland. The plants observed most frequently where heating has occurred are Sisymbrium loeselii, Artemisia vulgaris, Sonchus arvensis, Chenopodium album, Achillea millefolium, Cirsium arvense, Amaranthus retroflexus, Atriplex nitens and Solanum nigrum. Some new, rare species such as Portulaca oleracea, first noticed in 2011, may be added. Most of encroaching species are annual, alien archeophytes and neophytes. Native species are mainly perennials. The majority of these species show a tendency to form specimens of huge size (gigantism). The abundance of emitted CO2 and nitrogen compounds is the likely cause of this. Additionally, the plants growing there are not attacked by insects. The heating of the ground liquidates the natural seed bank. After cooling, these places are seeded by species providing seeds at that very moment (pioneer species). Heated places on the dumps allow plant growth even in the middle of winter. As the seasonal vegetation cycle is disturbed, plants may be found seeding, blooming and fruiting at the same time.

Geochemical markers and polycyclic aromatic hydrocarbons in solvent extracts from diesel engine particulate matter

Exhaust particulate from compression ignition (CI) engines running on engine and chassis dynamometers was studied. Particulate dichloromethane extracts were qualitatively and quantitatively analyzed for polycyclic aromatic hydrocarbons (PAHs) and biomarkers by gas chromatography with flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). PAH group profiles were made and the PAH group shares according to the number of rings (2 or 3; 4; 5 or more) as well as diagnostic indices were calculated. Values of geochemical ratios of selected biomarkers and alkyl aromatic hydrocarbons were compared with literature values. A geochemical interpretation was carried out using these values and biomarker and alkyl aromatic hydrocarbon distributions. It has been shown that geochemical features are unequivocally connected to the emission of fossil fuels and biofuels burned in CI engines. The effect of the exothermic combustion process is limited to low-molecular-weight compounds, which shows that the applied methodology permits source identification of PAHs coexisting in the particulate emitted.

Sources of organic pollution in particulate matter and soil of Silesian Agglomeration (Poland): evidence from geochemical markers.

The exact input of particular sources to polycyclic aromatic hydrocarbons (PAHs) concentrations in urban and industrial agglomerations is still not well recognized. The major breakthrough is possible using geochemical markers. In the air aerosol and soil samples from areas located in the direct influence of industry/traffic in Silesian Agglomeration (Poland), PAHs and other organic compounds were analyzed, including geochemical markers (biomarkers) and polar compounds from fossil fuels and biomass. Gas chromatography (GC-FID) and gas chromatography–mass spectrometry (GC–MS) were applied to investigate the composition of particulate matter and soil extracts. The results suggest that the predominant source of PAHs is fossil fuel. The presence and distribution of steranes, pentacyclic triterpenoids (i.e., hopanes and moretanes) and alkyl PAHs point to traffic emissions and fossil fuel combustion, mainly bituminous coal for power and heat purposes, as the main source of PAHs in the region. Moreover, the presence of fossil fuel biomarker in particulate matter and soil extracts from a rural site, previously considered to be free of organic pollution, requires a cautious interpretation for PAHs results. Apart from the fossil fuel, also other sources of contamination were identified in particulate matter extracts by their markers: phenols and levoglucosan for biomass and diisopropylnaphthalenes for printing materials combustion. The absence of polar biomass combustion indicators in soil extracts might be related to their higher reactivity.

Distribution of phenols related to self-heating and water washing on coal-waste dumps and in coaly material from the Bierawka river (Poland)

Abstract Several types of coal waste (freshly-dumped waste, self-heated waste and waste eroded by rain water), river sediments and river water were sampled. The aim was to identify the types of phenols present on the dumps together with their relative abundances. Gas chromatography-mass spectrometry (GC-MS) analyses of a large number of samples (234) statistically underpin the phenol distributions in the sample sets. The largest average relative contents (1.17-13.3%) of phenols occur in the self-heated samples. In these, relatively high amounts of phenol, C1- and C2-phenols reflect the thermal destruction of vitrinite. In fresh coal waste, C2- and C3-phenols that originated from the bacterial/fungal degradation and oxidation of vitrinite particles are the most common (0.6 rel.%). Water-washed coal waste and water samples contain lower quantities of phenols. In the river sediments, the phenols present are the result of bacterial- or fungal decay of coaly organic matter or are of industrial origin.

Chapter 14 – Thermal Transformations of Waste Rock at the Starzykowiec Coal Waste Dump, Poland

Large dumps of coal waste are a necessary consequence of coal mining. In some cases, the waste material undergoes self-heating and combustion that changes the nature of the organic- and mineral matter of the wastes. The range of the alterations depends on the properties of the waste rocks (maceral composition and rank of organic matter) and the heating history, especially the rate and duration of heating and the degree of access for air and moisture. The Starzykowiec dump located within Chwalowice coal mine (Upper Silesia, Poland) dates from the beginning of the previous century. It contains wastes that have been thermally altered to varying degrees—reflected in colors ranging from black through yellowish, orange, red, to white and in their structure (some altered wastes are hard and solid, others soft). A coal mud collector is located on the top of the dump. Some of the waste contains organic matter both visible under a microscope and as a bituminous fraction analyzed by GC-MS. Others contain organic matter only visible under a microscope or only a bituminous fraction analyzable by GC-MS or, in some, no organic matter at all. The alterations typically seen in the wastes indicate that the temperature rose slowly; macerals show paler colors, higher reflectance, and no porosity due to devolatilization. In some waste, their yellowish color and very high reflectance indicate a very pronounced degree of alteration. In other strongly altered waste, porous, yellowish organic matter is indicative of high heating rates. Mineral-matter compositions of the waste on the Starzykowiec dump also show a wide range of thermally induced changes. There are wastes where mineral matter is unchanged and others where primary compositions are completely transformed. High-temperature mineral phases, e.g. diopside, mullite, and indialite, may be formed. On the basis of the color of powdered samples, wastes can be divided into eight groups of different mineral compositions. However, mineral phases such as gypsum and other sulfates formed due to late-stage weathering can change the chemical compositions of the waste. The organic compounds present in dichloromethane extracts, the distributions of which were determined with GC-MS, include n-alkanes, acyclic isoprenoids, pentacyclic triterpanes (hopanes and moretanes), aromatic hydrocarbons together with their C1–C5 alkyl derivatives, and PAHs from naphthalene to perylene. Relative percentage contents of PAHs, and biomarker- and alkyl-PAHs ratios allow waste organic matter composition, geochemical features, and thermal transformations caused by self-heating to be assessed. Several diagnostic changes in biomarker distributions identified include the thermal removal of lighter compounds and related changes in Pr/Ph, MNR, DNR, and TNR values, and enrichment in C31 pentacyclic compared to C30 and C29 triterpanes. Geochemical parameters were correlated to each other and to vitrinite reflectance. Results indicate that biomarker- and aromatic-hydrocarbon parameters, normally applied in the assessment of organic matter thermal maturity, show comparable patterns in the coal waste. Correlations with vitrinite reflectance and between individual geochemical parameters agree with thermal evolution trends typical of coal-waste deposits unchanged by self-heating whereas, in rocks altered by self-heating, biomarker- and aromatic-hydrocarbon parameter values approximate those characterizing overheated organic matter and coal pyrolysates.

Distribution of coal and coal combustion related organic pollutants in the environment of the Upper Silesian Industrial Region

In this study, a large sample set (276) was separated into up to 15 groups, including coal, fly ash, total particulate matter, coal wastes, river sediments, and different water types. Grouping the sample set into these categories helped to identify the typical features of combustion or water-washing and compare them using newly developed polycyclic aromatic hydrocarbon diagnostic ratios. A wide range of organic pollutants were identified in samples, including aromatic and polycyclic hydrocarbons, nitrogen-heterocycles, sulphur-heterocycles + trithiolane, and polycyclic aromatic hydrocarbons substituted with oxygen functional groups. The distribution of compounds was significantly influenced by water washing or combustion. During the self-heating of coal wastes, secondary compounds such as chlorinated aromatics (chlorobenzene, chloroanthracene, etc.) or light sulphur compounds (e.g. benzenethiol and benzo[b]thiophene) were formed (synthesised). Since these compounds are generally absent in sedimentary organic matter, their origin may be connected with high-temperature formation in burning coal dumps. These compounds should be identified as persistent organic pollutants (POPs) in the environment. The newly defined diagnostic ratios have worked well in separating samples (petrogenic and pyrogenic) and have pointed out the effect of incomplete combustion on self-heated coal waste, ash from domestic furnaces, or water washing and biodegradation of the studied compounds.

Occurrence of organic phosphates in particulate matter of the vehicle exhausts and outdoor environment – A case study

The occurrence and concentrations of a wide range of organic phosphates (OPEs) in vehicles exhaust (VPM), ambient air particulate matter (APM), and soil of various urban environments were researched. VPM comes from passenger cars, commercial vehicles, marine and bus engines emitted in New European Driving Cycle tests whereas APM was sampled in several sites of the Upper Silesia region (Poland). APM and VPM collected on filters and soil from the same locations as APM sampling sites were extracted with dichloromethane and extracts analyzed by gas chromatography-mass spectrometry. The OPEs found include aryl phosphates such as triphenyl phosphate (TPhP) and tricresyl phosphate (TCP), alkyl phosphates - triethyl phosphate (TEP), tripropyl phosphate (TPP), tributyl phosphate (TBP) and tri(butoxyethyl)phosphate (TBEP), and alkylchlorinated phosphates including tris-(2-chloroisopropyl) phosphate (TCiPP) and tris(2-chloroethyl) phosphate (TCEP). Occurrence and concentrations of these compounds in the PM investigated are highly variable. It was found that total concentrations in APM are directly related to traffic density in particular sites of the urban environment and a style of a vehicle driving. The highest emission of OPEs was found at a crossroad and city center sites where traffic is the densest and vehicles stops and starts are frequent. Village and residential areas were less exposed to OPEs emission. Since OPEs concentrations show exponential correlations to each other also human exposure to these compounds increases exponentially with increasing traffic density. High TEP and TBP level is tentatively proposed as an indicator of emission from petrol-fueled cars. Concentrations of OPEs in some soil are related to their emission to the air and resistance to degradation of a particular compound since only the most resistant TCiPP and TPhP were identified in soil extracts.