No abstract

The very fast growing Oxytree (Paulownia Clon in Vitro 112) is marketed as a promising new energy crop. The tree has characteristically large leaves, thrives in warmer climates, and requires initial pruning for enhanced biomass production in later years. We explored valorizing the waste biomass of initial (first year) pruning via thermal treatment. Specifically, we used torrefaction (‘roasting’) to produce biochar with improved fuel properties. Here for the first time, we examined and summarized the fuel properties data of raw biomass of Oxytree pruning and biochars generated via torrefaction. The effects of torrefaction temperature (200~300 °C), process time (20~60 min), soil type, and agro-technical cultivation practices (geotextile and drip irrigation) on fuel properties of the resulting biochars were summarized. The dataset contains results of thermogravimetric analysis (TGA) as well as proximate and ultimate analyses of Oxytree biomass and generated biochars. The presented data are useful in determining Oxytree torrefaction reaction kinetics and further techno-economical modeling of the feasibility of Oxytree valorization via torrefaction. Oxytree torrefaction could be exploited as part of valorization resulting from a synergy between a high yield crop with the efficient production of high-quality renewable fuel.

This study aimed to identify and quantify the chemical composition and polyphenolic profile of 19 cultivars of Chaenomeles × superba, Chaenomeles japonica, and Chaenomeles speciosa by liquid chromatography coupled with photodiode array detector and quadrupole time-of-flight electrospray ionization mass spectrometry (LC-PDA-QTOF-ESI-MS). Antioxidant (ABTS on-line, ABTS, FRAP, and ORAC), as well as in vitro biological activities, i.e., the ability to inhibit α-amylase, α-glucosidase, pancreatic lipase, acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and 15-lipoxygenase (15-LOX) were determined. Most of the Chaenomeles species and cultivars analyzed in this study have not been examined in this respect until now. Fruits contained 30.26 to 195.05 mg of vitamin C, 0.65 to 1.69 g of pectin, 0.32 to 0.64 g of ash, 0.60 to 3.98 g of sugars, and 41.64 to 110.31 g of organic acids in 100 g fresh weight. The lowest content of total polyphenols showed C. speciosa ‘Rubra’ (57.84 g/kg dry weight, dw) while C. × superba ’Nicoline’ (170.38 g/kg dw) exhibited the highest concentration of those compounds. In the phenolic compounds, polymeric procyanidin fraction predominated (65%) with procyanidin B2, C1, and (−)-epicatechin the most abundant. The antioxidant capacity measured by ABTS assay was mainly formed by polymeric procyanidins and flavan-3-ols, which was confirmed by ABTS on-line profiling. Chaenomeles fruits showed high potential for inhibition of α-glucosidase and pancreatic lipase. The analyzed cultivars displayed greater potential for acetylcholinesterase (AChE) inhibition than for butyrylcholinesterase (BuChE). The data indicate that Chaenomeles fruits could be regarded as a promising source of bioactive functional food.

Biowaste generated in the process of Oxytree cultivation and logging represents a potential source of energy. Torrefaction (a.k.a. low-temperature pyrolysis) is one of the methods proposed for the valorization of woody biomass. Still, energy is required for the torrefaction process during which the raw biomass becomes torrefied biomass with fuel properties similar to those of lignite coal. In this work, models describing the influence of torrefaction temperature and residence time on the resulting fuel properties (mass and energy yields, energy densification ratio, organic matter and ash content, combustible parts, lower and higher heating values, CHONS content, H:C and O:C ratios) were proposed according to the Akaike criterion. The degree of the models’ parameters matching the raw data expressed as the determination coefficient (R2) ranged from 0.52 to 0.92. Each model parameter was statistically significant (p < 0.05). Estimations of the value and quantity of the produced torrefied biomass from 1 Mg of biomass residues were made based on two models and a set of simple assumptions. The value of torrefied biomass (€123.4·Mg−1) was estimated based on the price of commercially available coal fuel and its lower heating value (LHV) for biomass moisture content of 50%, torrefaction for 20 min at 200 °C. This research could be useful to inform techno-economic analyses and decision-making process pertaining to the valorization of pruned biomass residues.

Oxytree is a fast-growing energy crop with C4 photosynthesis. In this research, for the first time, the torrefaction kinetic parameters of pruned Oxytree biomass (Paulownia clon in Vitro 112) were determined. The influence of the Oxytree cultivation method and soil class on the kinetic parameters of the torrefaction was also investigated. Oxytree pruned biomass from a first-year plantation was subjected to torrefaction within temperature range from 200 to 300 °C and under anaerobic conditions in the laboratory-scale batch reactor. The mass loss was measured continuously during the process. The relative mass loss increased from 1.22% to 19.56% with the increase of the process temperature. The first-order constant rate reaction (k) values increased from 1.26 × 10−5 s−1 to 7.69 × 10−5 s−1 with the increase in temperature. The average activation energy for the pruned biomass of Oxytree torrefaction was 36.5 kJ∙mol−1. Statistical analysis showed no significant (p < 0.05) effect of the Oxytree cultivation method and soil class on the k value. The results of this research could be useful for the valorization of energy crops such as Oxytree and optimization of waste-to-carbon and waste-to-energy processes.