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This study evaluated the bioenergy potential of Wolffia arrhiza via pyrolysis. The biomass was collected from the pond receiving city wastewater. Oven dried powdered biomass was exposed to thermal degradation at three heating rates (10, 30 and 50° C min −1 ) using Thermogravimetry–Differential Scanning Calorimetry analyzer in an inert environment. Data obtained were subjected to the isoconversional models of Kissenger-Akahira-Sunose (KSA) and Flynn–Wall–Ozawa (FWO) to elucidate the reaction chemistry. Kinetic parameters including, E a (136–172 kJmol −1 ) and Gibb’s free energy (171 kJmol −1 ) showed the remarkable bioenergy potential of the biomass. The average enthalpies indicated that the product formation is favored during pyrolysis. Advanced coupled TG-FTIR-MS analyses showed the evolved gases to contain the compounds containing C O functional groups (aldehydes, ketones), aromatic and aliphatic hydrocarbons as major pyrolytic products. This low-cost abundant biomass may be used to produce energy and chemicals in a cost-efficient and environmentally friendly way. [ABSTRACT FROM AUTHOR]

This work was focused on understanding the pyrolysis of Typha latifolia . Kinetics, thermodynamics parameters and pyrolysis reaction mechanism were studied using thermogravimetric data. Based on activation energies and conversion points, two regions of pyrolysis were established. Region-I occurred between the conversion rate 0.1–0.4 with peak temperatures 538 K, 555 K, 556 K at the heating rates of 10 K min −1 , 30 K min −1 , and 50 K min −1 , respectively. Similarly, the Region-II occurred between 0.4 and 0.8 with peak temperatures of 606 K, 621 K, 623 K at same heating rates. The best model was diffusion mechanism in Region-I. In Region-II, the reaction order was shown to be 2nd and 3rd. The values of activation energy calculated using FWO and KAS methods (134–204 kJ mol −1 ) remained same in both regions reflecting that the best reaction mechanism was predicted. Kinetics and thermodynamic parameters including E , Δ H , Δ S , Δ G shown that T. latifolia biomass is a remarkable feedstock for bioenergy. [ABSTRACT FROM AUTHOR]

• The feasibility of Maple Leaf Waste (MLW) for biofuel synthesis is reported. • Different Kinetic models were developed and compared with each other. • Activation energy through all models were ranging from 75 to 91 kJ mol−1. • All thermodynamic results reflect the remarkable bioenergy potential of the MLW. The present study aims to evaluate the feasibility of Maple Leaf Waste (MLW) for the first time to produce biofuel-bioenergy and chemicals. It is meaningful to understand the thermochemical conversion and degradation pattern of the MLW to evaluate its biofuel-bioenergy potential. Different degradation stages and zones based on temperature and mass loss were identified to understand the pyrolytic behaviour in depth. Four different heating rates were used to conduct kinetic and thermodynamic analysis. The pyrolysis temperature was concluded ranged from 200 °C to 430 °C at all heating rates to obtain maximum bioenergy products. The kinetic parameters of pyrolysis were obtained by analysing through iso-conversional models of Kissinger-Akahira-Sunose (KAS), Friedman and Flynn–Wall–Ozawa (FWO). The average values of activation energies (75–91 kJ mol−1), high heating values (16.32 MJ kg−1), Gibb's free energies (261–269 kJ mol−1) and change in enthalpy (68–85 kJ mol−1) have shown the significant potential for bioenergy production and suitability of co-pyrolysis with other waste and biomass feedstock. [ABSTRACT FROM AUTHOR]

• A low-cost, contamination free, easy harvesting of microalgae was established. • The lipids from the algal biomass was extracted after biochemical analyses. • The residual algal biomass was pyrolyzed at four heating rates. • Kinetics and thermodynamic parameters demonstrated the suitability for pyrolysis. • An integrated approach of biological and thermal transformation is proposed. The suitability of integrating biological and thermal transformation of microalgal biomass to design a biorefinery was studied. The mixed cultivation of Chlorella sp. and Bracteacoccus sp. in city wastewater produced 12 g L−1 of biomass (0.77 g L−1 day−1) and removed nitrates and phosphates by 68% and 75%, respectively. Microalgae outcompeted the contaminating microbes by raising the pH of wastewater to 9.93. The lipid-free residual biomass was pyrolyzed at four heating rates (10, 20, 30, 40 °C min−1) which showed a three-stage pyrolysis. The activation energies (182–256 kJ mol−1) and their corresponding lower enthalpies at the conversional fractions from 0.2 to 0.6 indicated that product formation was being favored. The values of pre-exponential factors (1015-17 s−1), Gibbs free energy (159–190 kJ mol−1) and entropy (43–81 J mol−1) showed efficient pyrolysis. The data may lead to establish a robust microalgal biorefinery to produce biomass and energy along with primary treatment of city wastewater. [ABSTRACT FROM AUTHOR]

Baijiu (Chinese liquor) industry is the world-renowned industry to produce high-quality liquor using mixed biomass feedstocks including sorghum, wheat, and rice bran. A huge amount of Baijiu Diuzao (residual solid waste) is produced every 1–3 months after the fermentation. The present study was focused on evaluating the bioenergy potential of the Chinese liquor industry waste for the very first time. The collected sample was subjected to thermal degradation in an inert environment at three heating rates including 10, 30 and 50 Kmin -1 . It was shown that pyrolysis of this waste followed a three-stage degradation pattern, with a loss of 7.49% of the mass during the first stage at T ≤ 130 °C. While the second stage showed two zones ranging from 130 to 373 °C with an overall 51.12% of the mass loss. The third stage occurred above 373 °C and showed 16.08% loss in the mass. The released gases were subjected to TG-FTIR-MS analyses to monitor the composition and abundance of the gases where C O groups (aldehydes, ketonic and carboxylic) and hydrocarbons were shown to be the dominating functional groups. Moreover, the data were subjected to kinetics, thermodynamics and reaction mechanism analyses using KSA (Kissinger-Akahira-Sunose), FWO (Flynn-Wall-Ozawa), Vyazovkin and CR (Coats-Redfern) methods. Where, the activation energies (70–195 kJ mol −1 ), Gibbs free energy (177–185 kJ mol −1 ) and lower difference of enthalpy (Δ H =  ∼5 kJ mol −1 ) indicated remarkable bioenergy potential of this waste either through pyrolysis or co-pyrolysis. The artificial neural network ( R 2  = 0.99) and reaction mechanism analyses indicated that the best thermal degradation chemistry was performed and described. This study will lead to establishing a thermal transformation strategy of this abundant and low-cost biological resource into energy and valuable chemicals in the cleanest manner. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the thermal degradation of grass ( Cymbopogon schoenanthus ) under an inert environment at three heating rates, including 10, 30, and 50 °C min −1 in order to evaluate its bioenergy potential. Pyrolysis experiments were performed in a simultaneous Thermogravimetry–Differential Scanning Calorimetry analyzer. Thermal data were used to analyze kinetic parameters through isoconversional models of Flynn-Wall-Ozawa (FWO) and Kissenger-Akahira-Sunose (KSA) methods. The pre-exponential factors values have shown the reaction to follow first order kinetics. Activation energy values were shown to be 84–193 and 96–192 kJ mol −1 as calculated by KSA and FWO methods, respectively. Differences between activation energy and enthalpy of reaction values (∼5 to 6 kJ mol −1 ) showed product formation is favorable. The Gibb’s free energy (173–177 kJ mol −1 ) and High Heating Value (15.00 MJ kg −1 ) have shown the considerable bioenergy potential of this low-cost biomass. [ABSTRACT FROM AUTHOR]