40 research outputs found
Atrazine, triketone herbicides, and their degradation products in sediment, soil and surface water samples in Poland
Evaluation of the Feasibility of Using TCR-Derived Chars from Selected Biomass Wastes and MSW Fractions in CO2 Sequestration on Degraded and Post-Industrial Areas
Thermo-catalytic reforming (TCR) of waste solid grade laminate
Thermo-catalytic reforming (TCR) is defined as intermediate pyrolysis at moderate temperatures and heating rates with subsequent reforming at elevated temperatures using biochar as a catalyst. TCR experiments were carried out to pyrolyze and subsequently reform Solid Grade Laminate (SGL) waste. SGL is a Kraft paper-derived product and as it is widely used in many applications, high volumes of waste laminate must be disposed of at end of life. To assess TCR for SGL waste treatment, the characterisation of the initial feedstock was accomplished, and it concluded that SGL is suitable to be processed via TCR. The main energy carrier products (char, oil and syngas) were generated by TCR in a 2鈥痥g/h pilot-scale reactor under a pyrolysis temperature of 500鈥癈 and reforming temperature of 650鈥癈, respectively. The mass balance analysis demonstrated that 50鈥痺t% of the initial feedstock was comprehensively converted to syngas, 28鈥痺t% to char and 22鈥痺t% to a liquid fraction containing both water (17鈥痺t%) and organics (5鈥痺t%). The oil showed good properties as its HHV reached a value of 32.72鈥疢J/kg, with low oxygen and sulphur contents. However further processing is required for the fuels to be within suitable limits for use as drop-in fuels for vehicles. The syngas was found to be rich in hydrogen especially when pyrolysis temperature reaches its maximum. Lastly, char revealed a calorific value of 25.94鈥疢J/kg and was of a stable form of carbon, exhibiting potential as a feedstock for gasification or as a carbon capture and storage medium. TCR of SGL represents novelty as this feedstock has not been tested before in a pyrolysis/reforming system and it is a promising route in an optic of circularity. In waste valorisation, TCR oil has a great opportunity to be used as a fuel or blended with other conventional fuels, thus supporting the shift towards more sustainable mobility
The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts
The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan
Trends for the Thermal Degradation of Polymeric Materials: Analysis of Available Techniques, Issues, and Opportunities
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
Fragments quantum descriptors in classification of bio-accumulative compounds
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
Trends for the Thermal Degradation of Polymeric Materials: Analysis of Available Techniques, Issues, and Opportunities
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
Toward Quantum-Informed Atom Pairs
In the following research, a new modification of traditional
atom
pairs is studied. The atom pairs are enriched with values originating
from quantum chemistry calculations. A random forest machine learning
algorithm is applied to model 10 different properties and biological
activities based on different molecular representations, and it is
evaluated via repeated cross-validation. The predictive power of modified
atom pairs, quantum atom pairs, are compared to the predictive powers
of traditional molecular representations known and widely applied
in cheminformatics. The root mean squared error (RMSE), R2, area under the receiver operating characteristic curve
(AUC) and balanced accuracy were used to evaluate the predictive power
of the applied molecular representations. Research has shown that
while performing regression tasks, quantum atom pairs provide better
fits to the data than do their precursors