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The aim of the following research is to assess the applicability of calculated quantum properties of molecular fragments as molecular descriptors in machine learning classification task. The research is based on bio-concentration and QM9-extended databases. A number of compounds with results from quantum-chemical calculations conducted with Psi4 quantum chemistry package was also added to the quantum properties database. Classification results are compared with a baseline of random guesses and predictions obtained with the traditional RDKit generated molecular descriptors. Chosen classification metrics show that results obtained with fragments quantum descriptors fall between results from baseline and those provided by molecular descriptors widely applied in cheminformatics. However a combination of both classes of features proved to yield the best results in the classification of test set.

Pickering emulsions have gained increasing interest because of their unique features, including easy preparation and stability. In contrast to classical emulsions, in Pickering emulsions, the stabilisers are solid micro/nanoparticles that accumulate on the surfaces of liquid phases. In addition to their stability, Pickering emulsions are less toxic and responsive to external stimuli, which make them versatile material that can be flexibly designed for specific applications, e.g., catalysis, pharmaceuticals and new materials. The potential toxicity and adverse impact on the environment of classic emulsions is related to the extractable nature of the water emulsifier. The impacts of some emulsifiers are related to not only their chemical natures but also their stabilities; after base or acid hydrolysis, some emulsifiers can be turned into sulphates and fatty alcohols, which are dangerous to aquatic life. In this paper, recent research on Pickering emulsion preparations is reviewed, with a focus on styrene as one of the main emulsion components. Moreover, the effects of the particle type and morphology and the critical parameters of the emulsion production process on emulsion properties and applications are discussed. Furthermore, the current and prospective applications of Pickering emulsion, such as in lithium-ion batteries and new vaccines, are presented.

This paper describes our current research into the removal of chlorine from commercial coals using leaching techniques in the Polish power industry. Chlorine removal studies were carried out for two samples from Polish power coals with the highest chlorine content. For the samples of output coals coming directly from mining plants, physicochemical property tests and technical and elemental analyses were performed along with a determination of the trace elemental content; furthermore, the physicochemical properties of ash obtained from the coals was tested, i.e., the chemical composition and fusion temperature of the ash. In addition, an analysis of the porous structure was carried out using physical sorption. Leaching tests for the removal of chlorine from coal were conducted to determine the impact of the following parameters on the degree of chlorine removal: temperatures in a range of 20–90 °C, times in a range of 30–240 min and coal fragmentation values in a range of 0.05–0.2 mm. For the purpose of this study, a Box-Behnken approach was used, and an analysis of variance (ANOVA) was used to determine the statistical significance of the variables studied. During each measurement, the dependence of the chlorine content of coal was determined after the leaching process on the tested Cld parameters (T, t, p); the tested parameters were then converted into values representing the dependency of each parameter on the degree of chlorine leaching β (T, t, p). The results of the studies, combined with the results of the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses, established economically optimal conditions for the removal of chlorine forms found in the tested coals, i.e., room temperature for HC2 coal samples and a temperature of 50 °C for HC1 coal samples, along with a leaching time of 120 min for both. Such conditions mostly ensure the removal of inorganic chlorine forms present in the coal material. Chlorine-free coal can be successfully used in combustion processes in the energy industry, thereby minimizing the adverse impact of chlorine on boiler components.

Coke oven liquor is one of the most contaminated liquid streams generated by the coal processing industry, thus its proper treatment and utilization is crucial for sustainable and environmentally neutral plant operation. The conventional wastewater treatment process comprises of chemical and biological processes. Within the current research the detailed role of chemical treatment is described. Commercially available iron-based coagulants (PIX100, PIX100COP, PIX113, PIX116) were tested to understand their removal efficiency and impact on the stream parameters. The influence of iron dose in the range of 300-500 mgFe/L on the process performance was also examined.It was found that the main role of chemical treatment was to bind toxicants harmful to activated sludge microorganisms, i.e. free and complex cyanides and sulphides. Among the tested iron-based conventional coagulants ferrous salts were more efficient than ferric salts. It was also observed that efficiency of the process strongly depended on wastewater properties (especially in regard to pH, which should be in the range of 9-10) and the coagulant selection needed to be done individually for a given wastewater type. The removal rates of particular contaminants were diversified and for free cyanides, complex cyanides and sulphides they were in the range of 23-91%, -156-77% and -357-98%, respectively. The expected, simultaneous removal of chemical oxygen demand (COD) during the treatment was not observed and even the parameter value increased after the process due to probable formation of compounds less vulnerable to oxidation.

New analytical laboratory tools for qualitative analysis of alternative and renewable solid biofuels have been developed. The primary target of this research was to develop and then validate a rapid method for semi-quantitative and qualitative analyses of the second-generation solid biofuels. X-ray fluorescence spectroscopy (XRF) was used in combination with a two-step, multivariate modelling procedure. First, soft independent modelling of class analogies (SIMCA) and classification and regression trees (C&RT) were applied to develop and validate the classifier, which enabled different biomass origins (agrarian biomass, forest biomass and furniture waste) and different possible sources of contamination (plastic, fossil fuels and lignin-cellulose after biomass acid hydrolysis) to be distinguished. Next, the model attempted to predict the concentration of individual components using partial least-squares regression (PLSR) models. In our study, we compared C&RT and SIMCA, and the classification models (algorithms) constructed by the C&RT method were characterised as having better properties than those based on SIMCA. The C&RT classification algorithm was able to predict the origin of biomass sources with a non-error rate greater than 95%. For predictions of the addition type, the non-error rate was greater than 91%. The developed methods can rapidly and adequately determine (qualitatively) the origin of biofuels and indicate possible sources of contamination.

This paper examines the degradation trends of polymeric materials during heat conversion and solvolysis processes. The presence of different fractions of polymeric materials, such as PET, PP, SBR, ABS, resin, and tier waste, necessitates the use of different procedures for degradation, transformation, and further elimination from the natural environment. A significant part of the work was devoted to discussing the issue of thermal pyrolysis, taking into account the chemical composition and the possible impact of the process reaction mechanism, the type of raw material used, and the influence of the process temperature on the yields of low, medium, and high boiling products. The issue was extended to the possibility of decomposition of polymers based on the use of catalytic additives for the improvement and efficiency of the process and the structural modification of reactors. The major goal of this investigation of these various options was to generate a spectrum of accessible strategies for polymeric material degradation. The optimal technique depends on the polymer type and predicted final product qualities. Different catalysts, such as ZSM-5 (Zeolite Socony Mobil-5 one of the most efficient catalysts), ZSM-5 with ammonium groups, and ZSM-5 with 10% Ni, improved the efficiency of several heating processes. The final products after polymeric material degradation were determined by the type and conditions of the degradation processes, results of the materials characterisation, and the scale of the reactors utilised.

Domestic waste combustion in central heating furnaces is illegal in many countries, including Poland, but unfortunately still occurs. These activities have a negative influence on the environment and human health. The local nature of this process makes it difficult to effectively counteract this phenomenon. Information campaigns about the impact of domestic waste combustion in central heating furnaces, especially the impact on human health, are necessary, but undertaking parallel control activities is much more important. To control activity, support is necessary to develop a suitable method to confirm domestic waste combustion in central heating furnaces. In the present preliminary study, we have investigated two methods. The first method is indirect, it is based on the analytical pyrolysis of organic residues in ash and provides direct information on the type of plastic subjected to combustion. The second method is based on the principal component analysis (PCA) of polycyclic aromatic hydrocarbon (PAH) concentrations in ash samples. Special attention was paid to sixteen PAHs: naphthalene, acenaphthene, acenaphthylene, fluorene, anthracene, phenanthrene, fluoranthene, pyrene, chrysene, benzo(a)anthracene, benzo(a)pyrene, benzo(e)pyrene, benzo(b+k)fluoranthene, dibenzo(a,h)anthracene+ indeno(1,2,3-cd)pyrene, benzo(g,h,i)perylene, and perylene.

The emission of pollutants into the air during the combustion of solid fuels in households is still a significant problem in many European Union countries, including Poland. These emissions are a significant source of many air pollutants formed during incomplete combustion and has been identified as one of the leading environmental risk factors for these populations. One of the solutions is to utilise thermally processed solid fuels. This article discusses the concentrations of pollutants emitted as a result of the combustion of conventional fuels and new low-emission fuel in out-of-class heaters. To gain better insight into the relationships between fuel type and flue gas quality, chemometric methods and variance analysis were used. Principal component analysis confirmed that the fuel type significantly influences the level of dust emissions and the total organic carbon and sum of polycyclic aromatic hydrocarbons in the dust. Clustering analysis identified how the concentrations of polycyclic aromatic hydrocarbons correlate with the amounts of dust and total organic carbon and showed that this correlation is proportional to the size of the molecule and consequently the number of aromatic rings. The use of low-emission fuel as a solid fuel in households, as our analyses have shown, can reduce the concentrations of dust, total organic carbon and polycyclic aromatic hydrocarbons by up to 50 times, thereby reducing air pollutants in cities.

Raphanus sativus var. longipinnatus, was exposed under experimental conditions to herbicides: rimsulfuron (RIM), administrated as (1) pure substance, (2) in commercially available formulation (RIMEL), (3) its degradation product: 4,6-dimethoxypyrimidin-2-amine (2ADP), (4) mesotrione (MES), (5) sulcotrione (SUL). Profiling and fingerprinting strategies, conducted by LC-MS/MS-FL, were employed to find markers of plant exposure to herbicide stress. The presence ofRIM metabolite in the tissues of plant exposed to this herbicide proved that it is necessary to determine both parent compound and its by-products to obtain reliable information on plant exposure to agrochemicals. A higher content of normetanephrine (NMN) (18-175%) and lower content of tyramine (TYR) (49-75%) and epinephrine (E) (75-83%) was observed in plant tissues exposed to RIM and 2ADP in comparison to blank sample. Therefore, NMN, TRY and E may be considered as markers of plant response to RIM. Non-target analysis enables to recognize the type of herbicide used during cultivation.

The program of potato protection recommended by the producers of agrochemicals requires application: thiamethoxam, lambda-cyhalothrin, deltamethrin, rimsulfuron and metalaxyl. Therefore, there is a risk that these pesticides are present in tubers, thus posing a toxicological risk to the consumer. In this respect, it is necessary to monitor the presence of these compounds in edible plants. Therefore, the aim of this paper was to develop a novel, simple and robust analytical procedure for simultaneous determination of above-mentioned pesticides in potato tubers. To develop an analytical procedure that fulfills SANTE demands, quick, easy, cheap, effective, rugged and safe method and matrix solid phase dispersion technique were investigated. The final determination was conducted by liquid chromatography with tandem mass spectrometry. The obtained experimental data were analyzed by analysis of variance. For the extraction of analytes, matrix solid phase dispersion with octadecyl sorbent and methanol as eluent was chosen, since it provides the validation parameters according to SANTE requirements (recovery: 77–111%, relative standard deviation: 1–10%, limit of quantification: 0.9–5.0 μg/kg). This innovative analytical procedure is a practical analytical tool, which was successfully proven by applying it for target pesticides determination in potato tuber samples of different varieties randomly chosen at local markets.

This study presents research that was conducted to determine the impact of biomass chemical composition on the characteristic ash melting behaviour of a biomass–coal blend made for use in the co-firing of power plants. It was conducted using two different types of biomass: wood biomass—pine (Pinus sylvestris L.) residue from sawmill, and agrarian biomass—miscanthus (Miscanthus giganteus). The design-of-experiments matrix was prepared using the simplex–lattice design method with four independent variables (i.e. coal A and B and biomass A and B). The characteristic melting points of ash (ash fusibility temperatures, i.e. the sintering, softening, melting and flowing temperatures) were used as the dependent variables, which were analysed under two atmospheres (e.g. oxidative and reductive). The analysis of the ash fusibility temperatures in oxidized and reduced atmospheres was conducted under accredited standards and test procedures using a PR-25/1750 furnace that was capable of reaching a maximum temperature of 1650 °C at a heating rate of 30 K min−1 to 1200 °C and 10 K min−1 between 1200 and 1650 °C, which provided an adequate zone of uniform temperature. In addition to the analyses of the ash melting point, full characterization of the physico-chemical properties of the applied fuels and their mixtures was performed. Based on the results of these analyses, the ash deposit behaviour was calculated, and its impact was discussed.

New analytical tools that enable analytical laboratories to quantitatively and qualitatively analyze alternative and renewable solid biofuels are needed. Fourier transform infrared (FTIR) spectroscopy was applied in combination with a two-step multivariate modelling procedure. In the first instance, a C&RT (classification and regression trees) model was developed and validated for use in distinguishing different biomass origins and possible sources of contamination. Once the solid fuels were correctly identified, the model was used to predict the concentrations of individual components using partial least squares regression (PLSR) models. The first C&RT model differentiated between the different classes of biofuel origins. Using the absorption intensity in the wavenumber range of 1800–400 cm−1, the prediction had a recovery of between 92% and 99%. The second C&RT model differentiated between the possible sources of contamination, which could be predicted with a recovery between 76% and 91% based on the FTIR results. Accuracy profiles based on the analysis results of validation samples were then calculated to prove the reliability of the developed regression models. The developed spectroscopic methods rapidly and adequately determined (qualitative analysis) the origin of the biofuels and indicated the possible source of contamination. The effects of two spectral data pre-processing methods (PQN & SNV) were also compared based on the accuracy of the developed models.

The aim of this study was to develop and validate a new rapid method for the qualitative analysis of solid biofuels obtained from a thermal treatment process. A new method for the qualitative confirmation of the second-generation solid bio-fuel origin was compared and assessed. The new method was compared with a method based on the concentration of 14 C carbon isotope in the studied material obtained from thermal conversion of a biomass. The developed method is intended to analyse the origin of the second-generation solid bio-fuels and is based on basic analytical fuel properties commonly measured in most laboratories. The process couples chemometric methods with proximate and ultimate analyses, heat of combustion and chemical composition of ash from second-generation solid bio-fuels. In light of the current European regulations, the second-generation bio-fuels obtained by the thermal conversion of biomass, e.g., bio-chars or torrefied biomass, are not classified as biomass. Consequently, the energy generated by these biofuels is not classified as energy generated from a renewable energy source. The currently available method, i.e., analysis of the 14 C content in samples of interest, might not be sufficiently sensitive to characterise materials from the co-pyrolysis of biomass and non-biodegradable material. Prompted by this situation, a new method for the qualitative confirmation of the second-generation solid bio-fuel origin was proposed. The BioFuel Classifier for Power Generation (BFC-PowerGen) provides a rapid and accurate determination of the origin of a fuel and can be used for controlling the quality of fuel derived from the thermal conversion of biomass. This new classifier, which is based on a classification and regression tree model, delivers a classification accuracy of at least 96%.

The article presents the possibilities of effective management of lignocellulosic waste by including it in the circular economy. The pyrolysis process was chosen as the thermal conversion method. This approach, due to a high flexibility of the obtained products, better quality of the solid residue (char), and the lower emission of pollutants into the atmosphere, e.g., SO2 and NOx, is a competitive solution compared to combustion process. Wood waste from alder and pine were analyzed. As part of laboratory tests, the elementary composition was determined, i.e., C, H, N, S, and O. The pyrolysis process was carried out at a temperature of 600 °C on an experimental stand for the conversion of solid fuels in a stationary bed. For the obtained data, using the Ansys Chemkin-Pro calculation tool, the detailed chemical composition of gaseous products of the pyrolysis process was modeled for a varying temperature range and residence time in the reactor. The studies have shown that for certain process conditions it is possible to obtain a high calorific value of pyrolytic gas, up to 25 MJ/m3.

The aim of this work was to study the content of seven heavy metal factors within different biomasses. The potential environmental effects associated with the release of these elements into the atmosphere were also studied by determining the emission factors for each of biomass. 31 samples of biomass which were classified into four groups, i.e.: wood biomass, herbaceous biomass, fruit biomass and aquatic biomass and analyzed with use of ICP-OES spectrometer. Performed results were analyzed in the context of the requirements of international standards, described in the EN ISO 17225:2014. Higher heavy metal contents than the limits described in the EN ISO 17225:2014 standard were detected within some of the studied biomass samples. Importantly, this is also related to the products available on the market, i.e., wood pellets or wood chips. Among the detected trace elements, the largest limit exceedance was for lead (wood chips from a rubber tree, pomace oil and palm kernel shells) and arsenic (Sea Balls). The highest emission factors were determined for the herbaceous, fruit and aquatic biomass. However, the wood chips studied were characterized by relatively high emission factors for each heavy metal. A comparison of the emission factors calculated for the studied biomass samples and for coal revealed that the total emission of heavy metals during the combustion of wood pellets and wood chips was lower than that calculated for hard coal.

In this study, the pyrolysis behaviours of marine microalgae biomass, Nannochloropsis gaditana, were investigated at three different temperatures (400, 500, 600 °C). Experiments were conducted in the presence of N2 with a flow rate of 50 cm3/h using a 1-kg fixed-bed reactor. The effects of pyrolysis conditions such as temperature on product yields were studied. The char, bio-oil, and gaseous samples obtained were analysed for elemental trace metals using inductively coupled plasma atomic emission spectroscopy (ICP-OES) and gas chromatography with mass detection (GC–MS). Raw Nannochloropsis gaditana samples were also analysed by pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS). Mass and energy balances were calculated. The results indicate that the bio-oil from the pyrolysis of Nannochloropsis gaditana under 600 °C had the highest heating value (12.6 MJ/kg) and was obtained with the highest efficiency (38–40%). Alkanes and alkenes, such as tetradecane, pentadecane, heptadecene, and octadecene, were identified in the liquid products, and the highest contents of alkanes and alkenes were determined in the bio-oil obtained under 500 °C. In these pyrolysis conditions, gaseous products exhibited the highest concentrations of methane (greater than 50% in the maximum range). These properties of the bio-oil and its gaseous products demonstrated that Nannochloropsis gaditana can be used as a renewable energy resource and chemical feedstock. The biochar from all processes contained almost 70% ash and, in this particular case, can be used as, for example, a fertilizer because it does not contain any heavy metals.

A new technology for removing mercury from coal by mild thermal coal treatment using a rotary kiln is presented. Experiments performed at the large laboratory scale show that 93% of the mercury is removed; moreover, the thermal properties of the fuel obtained from the process are also improved. In this article, we describe the physicochemical characteristics of the fuel under the test conditions and the properties of the products obtained during the removal process. The experiments were performed in an appropriately modified test system, and the net mass and energy losses do not exceed 5%. An economic analysis indicates that the proposed technology is cost-competitive with existing methods for removing mercury from flue gases after combustion.

Co-pyrolysis of lignin-rich materials with two types of plastic waste blends was evaluated. Blend 1 (B1) comprised 30% m/m styrene-butadiene rubber (SBR, from rubber granules used tires), 40% m/m polyethylene terephthalate (PET, from scrap bottles), and 30% m/m polypropylene (PP, from scrap bumpers). Blend 2 (B2) comprised 40% m/m PET (from scrap bottles), 30% m/m PP (from automotive scrap), and 30% m/m acrylonitrile-butadiene-styrene copolymer (ABS, from automotive scrap). The lignin-rich materials evaluated were wood biomass, agrarian biomass, and waste from furniture. The feedstock-to-product energy conversion efficiency (FP-ECE) was also studied. Samples were thermally treated from room temperature to 400 or 600 °C at a heating rate of 10 °C min −1 under N 2 at a flow rate of 3 dm 3 min −1 . In light of the experimental results, an appropriate temperature for the fixed-bed pyrolysis of biomass-plastic mixtures with various ratios was determined and the raw materials were pyrolysed under the same conditions. The solid (char), liquid and gaseous products of pyrolysis were analysed. The pyrolysis experiments and analysis of variance showed that the combination of biomass with plastic materials had a positive effect on the liquid and gas yields.

Tars obtained from the thermal conversion of biomass are an incredibly reach source of information regarding the type and composition of feed biomass as well as the process parameters. However, thus far, that information remains unobtainable due to a lack of analytical and data processing methods that can handle such an enormous set of chemical species. Herein, we present results obtained from one- and two-dimensional gas chromatography combined with chemical derivatization using silyl agents. This approach extended the range of compounds that can be analysed with the gas chromatography technique to include polyalcohols and polyphenols with low volatilities and medium thermal stabilities. The examined tars originated from the continuous torrefaction of wood biomass in the temperature range between 300 and 350 °C.