Amount Of Pyrolysis Products Research Articles

Effect of outdoor ageing on pyrolytic characteristics and kinetics of different organic components in waste photovoltaic panels

Pyrolysis is a potential approach for volume reduction and utilization of organic components in waste photovoltaic panels. During a usage period of 20–25 years, the physical and chemical properties of photovoltaic panels might undergo ageing and deterioration, thereby affecting their thermal decomposition characteristics. The characteristics of samples before and after ageing were studied using Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analyzer, and thermogravimetry-Fourier transform infrared spectroscopy-mass spectrometry. There were certain differences in the weight loss temperature, time, residual mass, and activation energy of the samples in the pyrolysis reaction. After ageing, the production of acetic acid and methane in ethylene vinyl acetate pyrolysis products increased, while the production of CO2 decreased. After ageing, Tedlar-Polyethylene Terephalate-Tedlar mainly produced water, carbon dioxide, and fluorocarbon compounds, and the percentage of harmful fluorocarbon compounds in the human body increased. Cyclosiloxane, CO2, and hydrocarbons containing C-H bond were detected in each weight-loss stage of aged silica gel. As the heating rate changed, the amount of pyrolysis products also changed. Controlling the sample's heating rate would help to lessen the quantity of hazardous pollutants that were produced. The influence of ageing on the weight loss of mixed samples was discussed. This study seeks to give a fundamental understanding of the physicochemical properties, pyrolysis behaviour, and volatiles of samples before and after ageing, thus providing helpful insights for the final disposal or recovery of waste photovoltaic panels through pyrolysis.

A study on pyrolysis of Canada thistle (Cirsium arvense) with titania based catalysts for bio-fuel production

The catalytic pyrolysis of Cirsium arvense was performed with titania supported catalysts under the operating conditions of 500°C, 40°C/min heating rate, 100mL/min N2 flow rate in a fixed bed reactor for biofuel production. The effect of catalysts on product yields was investigated. The amount of pyrolysis products (bio-char, bio-oil, gas) and the composition of the produced bio-oils were determined by proton nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FT-IR), gas chromatography/mass spectrometry (GC–MS) and elemental analysis (EA) techniques. Thistle bio-oils had lower O/C and H/C molar ratios compared to feedstock. The highest bio-char and bio-oil yields of 29.32wt% and 36.71wt% were obtained in the presence of Ce/TiO2 and Ni/TiO2 catalysts respectively. GC–MS identified 97 different compounds in the bio-oils obtained from thistle pyrolysis. 1H NMR analysis showed that the bio-oils contained ∼55–77% aliphatic and ∼6–19% aromatic structural units.

Catalytic pyrolysis of central German lignite in a semi-continuous rotary kiln — Performance of pulverized one-way ZSM-5 catalyst and ZSM-5-coated beads

Central German lignites with high numbers of aliphatic and bituminous molecular structures are potential feedstocks for light hydrocarbons as intermediates for the chemical industry. This study pursues a new approach to the direct conversion of lignites by heterogeneous catalysis under pyrolytic conditions and without additional hydrogenation. Promising results were achieved in lab-scale investigations with ZSM-5 catalyst and these results were confirmed at a semi-technical scale rotary kiln. ZSM-5-coated beads were examined as an interesting alternative for reutilization and simple separation from the solid pyrolysis products.Based on parameter studies, the maximum yields of low molecular hydrocarbons occurred at a reaction temperature of 500°C at a catalyst-to-coal ratio of 0.1 to 0.2 (maf). Comparison between the pulverized one-way ZSM-5 catalyst and ZSM-5-coated beads shows similar results concerning the amounts of pyrolysis products, especially gaseous alkenes like propene. At a certain catalyst-to-coal ratio, comparable results of propene liberation can be found also. The main reaction pathways were identified based on the distribution of the catalytic pyrolysis products, especially of low molecular hydrocarbons.

Examination of zinc adsorption capacity of soils treated with different pyrolysis products

Abstract Organic matter input into soils is essential regarding agricultural, environmental and soil science aspects as well. However, the application of the pyrolysed forms of biochars and materials with different organic matter content gained more attention in order to decrease the emission of the green house gases (CO2, N2O) from the soil. During pyrolysis, the materials containing high organic matter (biomass-originated organic matter) are heated in oxygen-free (or limited amount of oxygen) environment. As a result, the solid phase, which remains after eliminating the gases and liquid phase, is more stable compared to the original product, it cannot be mineralized easily in the soil and its utilization is more beneficial in terms of climatic aspects. Furthermore, it can improve soil structure and it can retain soil moisture and cations in the topsoil for long periods of time, which is very important for plants. In our experiment, the effects of biochar and bone char were examined on soils by zinc adsorption experiments. Based on our experiments, we concluded that the pyrolysis products can have significant Zn adsorption capacity compared to the soil. Bone ash can adsorb more Zn than the charcoal product. The Zn adsorption capacity of soils treated by pyrolysis products can be described by Langmuir adsorption isotherms. However, based on the amount of pyrolysis products, one or two term Langmuir isotherm fits well on the experiment data, which depends on the time the pyrolysis product has spent in the soil.

Pyrolysis of poly(2-propylheptyl acrylate)

The thermal destruction processes of poly(2- propylheptyl acrylate) take place at the range of tempera- ture 250-950 C was investigated using pyrolysis-gas chromatography. Knowledge of the types and amounts of pyrolysis products will provide important information about the thermal degradation of homopolymer poly(2- propylheptyl acrylate) and the mechanisms involved. Unsaturated monomers 2-propylheptyl acrylate and 2-pro- pylheptyl methacrylate, according to by-product alkyl alcohol 2-propylheptylalcohol, alkene 2-propylheptene-1, carbon dioxide, carbon monoxide, methane, and ethane were formed during thermal degradation of poly(2-pro- pylheptyl acrylate).

Isothermal co-pyrolysis of hazelnut shell and ultra-high molecular weight polyethylene: The effect of temperature and composition on the amount of pyrolysis products

Solid wastes compromise biomass and plastics in terms of energy recuperation. Pyrolysis is the promising process in thermochemical conversions. In this study, isothermal co-pyrolysis of hazelnut shell and ultra-high molecular weight polyethylene (UHMWPE) mixtures was executed in hand made pyrolysis reactor. The effect of temperature and composition on liquid, solid and gas yields was clarified with descriptive charts. It can be definitely stated that there are interactions between components which are called synergistic effects. Temperature change and ratio of UHMWPE do not alter solid product yield significantly. Co-existence of hazelnut shell and UHMWPE renders gas products in expense of liquid at all temperature and composition conditions. Liquid products were collected separately as heavy and light liquid. Liquid fuel is preferred to gas and solid ones due to commercial reasons. Combustible heavy liquid increases synergistically with increasing UHMWPE ratio. Here, synergistically means it is higher than mathematical calculation. It was found that just at 515 °C and 0.5:1.5 (hazelnut shell/UHMWPE) composition total liquid product is above the calculated values. Additionally, 1.0:1.0 composition again at the same temperature produces highest heavy liquid yield.

Identification of acrylate copolymers using pyrolysis and gas chromatography

A combination of pyrolysis and gas chromatography were used to investigate thermal degradation products formed from acrylic copolymers containing alkyl acrylate and methacrylate. The method provided an analytical tool for characterizing the chemical composition and structure of the degradation products. Thermal degradation of the synthesized copolymers was analyzed using isothermal (250 °C) pyrolysis–gas chromatography. The degradation process, and the nature and amount of pyrolysis products, provides relevant information about the thermal degradation of acrylic copolymers and the mechanism of pyrolysis. During pyrolysis, the formation of corresponding olefins, alcohols, acrylates and methacrylate was observed.

Direct temperature mass spectrometric study on the depth-dependent compositional gradients of aged triterpenoid varnishes

The depth profiles of aged dammar and mastic films, which were uncovered by optimized KrF excimer laser ablation (248 nm, 25 ns), were examined by direct temperature-resolved mass spectrometry (DTMS). The results establish the generation of depth-dependent compositional gradients in triterpenoid resins as a consequence of aging, for the first time on the molecular level. Electron ionization DTMS total ion currents show that the required temperature to volatilize the polar compounds and the relative amount of pyrolysis products of the high molecular weight condensed fraction is reduced when the upper layer of varying thickness of the films had been removed by the laser. The relative abundance of characteristic ion fragments of known oxidized triterpenoid compounds gradually decreased with depth. In contrast, the ion fragments of original resin molecules became more abundant with depth. The mass spectra of the bulk of the films resembled that of the control samples, which were not subjected to aging. Multivariant factor discriminant analysis quantified the oxidative gradients and showed that a depth of 15 μm from the surface of the aged films is the threshold between highly and much less deteriorated material.

The thermal degradation of acrylic pressure-sensitive adhesives based on butyl acrylate and acrylic acid

The thermal degradation of acrylic pressure-sensitive adhesives at 250 °C was investigated using pyrolysis-gas chromatography. Knowledge of the types and amounts of pyrolysis products will provide important information on the thermal degradation of acrylic adhesives and the mechanisms involved. Unsaturated monomers including butyl acrylate and butyl methacrylate were formed during thermal degradation of butyl acrylate–acrylic acid copolymers. As a result of side chain reactions in the thermal destruction of the butyl acrylate–acrylic acid-based self-adhesives, a remarkable amount of butyl alcohol was produced. The unsaturated monomers formed as a result of thermal degradation could potentially be used in a new polymerization process.

Organic geochemistry of the kerogen and bitumen from the Ohio Shale by pyrolysis-gas chromatography

An exposure of the Ohio Shale at Bristol Ridge, Ohio in the Bellefontaine Outlier was sampled into 53 channel units. Proximate and elemental (CHN) analyses were performed on these samples to determine the concentration of organic matter. The organic content averaged 6.82% with the highest both in the lower half (11.08%) and extreme upper part (10.43%) of the section. Fragmentation of the kerogen of each of the whole rock samples was accomplished by pyrolyzing for 10 s at 750°C in the injection port of a gas chromatograph with a FID detector. The concentration and distribution of the diagnostic hydrocarbons fragmented at this temperature were used to infer the molecular construction of the high molecular weight kerogens. The suite of identified hydrocarbons for each of the samples throughout the section was similar, but a very large fluctuation in the amount of pyrolysis products was observed. This fluctuation is strongly related to organic richness as defined by the proximate and elemental analyses. The identification of diagnostic normal alkanes and aromatics and SCI indicates that the kerogen assemblage is composed of both marine and terrestial components — most likely a mixed Type II kerogen. The contribution of individual aromatic and normal alkanes is variable, which suggests that there were minor fluctuations in the proportions of terrestrial and marine organic matter during decomposition. Bitumen pyrolized from the whole rock and bitumen removed by Soxhlet extraction using a 4:1 benzene/methanol solvent mixture were analyzed. Comparison of these two techniques yield similar pristane/phytane ratios and Carbon Preference Index (CPI) values. On decomposition the whole rock bitumen exhibited a mean pristane/phytane ratio of 1.5 and a mean CPI value of 1.4, whereas the Soxhlet-extracted bitumen exhibited a mean pristane/phytane ratio of 1.6 and a mean value of 1.3. The low pristane/phytane ratios from this outlier indicates a possible marine environment, with reducing conditions existing immediately below the sediment-water interface. The CPI values also indicate the sedimentary sequence is thermally immature. Reflectance of the vitrinite (% R o 0.05) and fluorescence ( Q 0.93) of the algal bodies indicate a maturation at the beginning of the oil window or at boundary between thermal immaturity and maturity.

微粉体の表面改質と付着基の反応性 種々な有機シリル塩化物によるシリカゲルの表面処理と付着基の化学的性状

The silica gel was treated with the organ-silyl chlorides, i. e., trimethylchlorosilane, n-butylchlorosilane, l-chloropropyltrichlorosilane, phenyltrichlorosilane, phenylmethylchlorosi lane, diphenylmethylchlorosilane and chloromethyldimethylchlorosilane and the hexamethyldisilazane which react with surface silanol at room temperature, respectively. The identification and reactivity of the surface group and surface properties of the surface-treated silica gels were investigated from the microanalysis, ir-spectra, pyrolysis, dispersive properties and the surface reaction. The surface of silica gels treated with organo-silyl chlorides consisted of the organo-silyl groups of the reagents used, while the one treated with hexamethyldisilazane consisted of trimethylsilyl groups. These silica gels were hydrophobic. The Cl in the surface group of the silica gel treated with l-chloropropyltrichlorosilane or chloromethyldimethylsilane was easily displaced with an OH-groud by immersing it in NH4OH aq. solution. The pyrolysis of the surface-treated silica gels occurred at a higher temperature than that of silica gels treated with alcohols, the amount of pyrolysis products was smaller than that of the latter. The silica gels after pyrolysis had an apparent deposit of carbon. Since HCl was not found in the pyrolysis products of that treated with organo-silyl di- or trichlorides, except for chloroalkylsilyl chlorides, the unreacted Cl included in reagents was found to be easily displaced with OH due to moisture in the air. The pyrolysis products of the silica gels treated with organo-silylchlorides, excep for chloroalkylsilyl chlorides, consisted of the corresponding olefine were included in the pyrolysis of the latter.