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The pyrolysis kinetics of invasive plantSpartina anglicabiomass was investigated via a thermogravimetric (TG) analyzer from 50 to 800°C in an inert argon atmosphere at different heating rates of 5–30°C/min, and the kinetic parameters were deduced by Starink and master-plots methods. The results showed that three stages appeared in the thermal degradation process, and the mean value of activation energy was calculated to be 291.57 kJ/mol by the Starink method. It suggested that the most probable pyrolysis kinetic model wasg(α) = [−ln(1-α)]4deduced by the master-plots method, which meant a random nucleation and nuclei growth mechanism. These results provided fundamental useful information for describing the pyrolysis process, and the subsequent designing and running of a pyrolytic processing system usingS. anglicaas feedstock. [ABSTRACT FROM PUBLISHER]

Several grasses are among the agricultural wastes generated annually in a large quantity during farming activities. In this study, thermogravimetric analysis was used to evaluate the fuel properties of a number of grasses, includingAeluropus sinensis, Conyza canadensis, Imperata cylindrica, andSetaria viridis. The pyrolysis behavior was also compared with the other biomasses. The thermal reaction systems fitted well with the distributed activation energy model and the global kinetic model and it is obvious that the values ofEandk0calculated by the distributed activation energy model were much higher than that of the global kinetic model. [ABSTRACT FROM PUBLISHER]

The optimal reaction model for analysis of thermal decomposition of various types of biomasses is currently under debate. Four established models for the kinetic analysis ofPolygonum lapathifoliumwere employed in this study: double extrapolation method, Flynn–Wall–Ozawa method (FWO), distributed activation energy model (DAEM), and global kinetic model. The values of activation energy and frequency factor calculated by global kinetic model are much lower than that of the other three methods. Moreover, it has been demonstrated that the activation energy analyzed by FWO method and DAEM is widely distributed and is not directly related to the heating rates, which are more objective than double extrapolation method and global kinetic model. [ABSTRACT FROM PUBLISHER]

The use of non-food biomass for bio-oils production appears to be an important trend for renewable energy in China. Biomass, in the form of marine macro-algae, is becoming popular among new renewable energy sources. Fast pyrolysis is one of the most important thermal conversion processes from biomass to bio-fuel. In this work, the marine green tide macroalgaeEnteromorpha proliferawas converted into bio-oil by fast pyrolysis in a free-fall reactor at different temperatures ranging from 100 to 750°C. The bio-oil obtained was analyzed by elemental, gas chromatography-mass spectrometer, and Fourier transform infrared spectroscopy analysis. The results showed that the average heat value was 25.33 MJ kg−1and the oxygen content was 30.27 wt%. The results suggested thatE. proliferapresents as a good bio-oil feedstock candidate. [ABSTRACT FROM PUBLISHER]

The marine macroalgae green tides occurring frequently produced a great quantity of macroalgal wastes from 2007 to 2011 in China. The pyrolytic characteristics and kinetics of one kind of marine green tide macroalgae, Enteromorpha prolifera, was investigated by the thermogravimetric analysis method at heating rates of 10, 20, 30, 40, 50°C/min. The corresponding activation energy E and the pre-exponential factor A were calculated and the mechanism functions were determined by double extrapolation and Flynn-Wall-Ozawa methods based on the thermogravimetric data. The results show that the optimum mechanism can be described by the Zhuralev, Lesokin, and Tempelmen equation (G(α) = {[1/(1 − α]1/3 − 1}2) for E. prolifera in pyrolysis temperatures that range from 240 to 290°C, and the thermolysis mechanism is a three-dimensional diffusion process in the main pyrolysis process. It indicates that E. prolifera has low thermal stability for pyrolysis and is a potential biomass energy resource. [ABSTRACT FROM PUBLISHER]

The pyrolytic kinetics of Jerusalem artichoke stalk, cornstalk, and sawdust (the latter two served as control) were investigated using a thermogravimetric analysis method under an inert atmosphere at heating rates of 5, 10, 20, and 30°C/min from 50 to 800°C. For Jerusalem artichoke stalk, starting with the dehydration step between 30 and 150°C, the main thermal decomposition process showed two distinct degradation zones, corresponding to the devolatilization step between 200 and 400°C and the combustion step between 400 and 600°C. Kinetic expressions for the degradation rate in devolatilization and combustion steps have been obtained for Jerusalem artichoke stalk with Popescu, Flynn-Wall-Ozawa, and Kissinger-Akahira-Sunose methods. The results showed that the model agreed well with the experimental data and provided useful information for the design of a pyrolytic processing system using Jerusalem artichoke stalk as feedstock to produce bio-fuel. [ABSTRACT FROM PUBLISHER]