The Bamboo species accounts for almost 1% of the Earth’s forested area with an exceptionally fast growth peaking up to 7.5–100 cm per day during the growing period, making it an unique species with ...respect to measuring and monitoring using conventional forest inventory tools. In addition their widespread coverage and quick growth make them a critical component of the terrestrial carbon cycle and for mitigating the impacts of climate change. In this study, the capability of using airborne Light Detection and Ranging (LiDAR) data for estimating canopy structure and biomass of Moso bamboo (Phyllostachys pubescens) was assessed, which is one of the most valuable and widely distributed bamboo species in the subtropical forests of south China. To do so, we first evaluated the accuracy of using LiDAR data to interpolate the underlying ground terrain under bamboo forests and developed uncertainty surfaces using both LiDAR-derived vegetation and topographic metrics and a Random Forest (RF) classifier. Second, we utilized Principal Component Analysis (PCA) to quantify the variation of the vertical distribution of LiDAR-derived effective Leaf Area Index (LAI) of bamboo stands, and fitted regression models between selected LiDAR metrics and the field-measured attributes such mean height, DBH and biomass components (i.e., culm, branch, foliage and aboveground biomass (AGB)) across a range of management strategies. Once models were developed, the results were spatially extrapolated and compared across the bamboo stands. Results indicated that the LiDAR interpolated DTMs were accurate even under the dense intensively managed bamboo stands (RMSE = 0.117–0.126 m) as well as under secondary stands (RMSE = 0.102 m) with rugged terrain and near-ground dense vegetation. The development of uncertainty maps of terrain was valuable when examining the magnitude and spatial distribution of potential errors in the DTMs. The middle height intervals (i.e., HI4 and HI5) within the bamboo cumulative effective LAI profiles explained more variances by PCA analysis in the bamboo stands. Moso bamboo AGB was well predicted by the LiDAR metrics (R2 = 0.59–0.87, rRMSE = 11.92–21.11%) with percentile heights (h25-h95) and the coefficient of variation of height (hcv) having the highest relative importances for estimating AGB and culm biomass. The hcv explained the most variance in branch and foliage biomass. According to the spatial extrapolation results, areas of relatively low biomass were found on secondary stands (AGB = 49.42 ± 14.16 Mg ha−1), whereas the intensively managed stands (AGB = 173.47 ± 34.16 Mg ha−1) have much higher AGB and biomass components, followed by the extensively managed bamboo stands (AGB = 67.61 ± 13.10 Mg ha−1). This study demonstrated the potential benefits of using airborne LiDAR to accurately derive high resolution DTMs, characterize vertical structure of canopy and estimate the magnitude and distribution of biomass within Moso bamboo forests, providing key data for regional ecological, environmental and global carbon cycle models.
Batch adsorption experiments were conducted for the adsorption of Cd (II) ions from aqueous solution by bamboo charcoal. The results showed that the adsorption of Cd (II) ions was very fast initially ...and the equilibrium time was 6
h. High pH (≥8.0) was favorable for the adsorption and removal of Cd (II) ions. Higher initial Cd concentrations led to lower removal percentages but higher adsorption capacity. As the adsorbent dose increased, the removal of Cd increased, while the adsorption capacity decreased. Adsorption kinetics of Cd (II) ions onto bamboo charcoal could be best described by the pseudo-second-order model. The adsorption behavior of Cd (II) ions fitted Langmuir, Temkin and Freundlich isotherms well, but followed Langmuir isotherm most precisely, with a maximum adsorption capacity of 12.08
mg/g. EDS analysis confirmed that Cd (II) was adsorbed onto bamboo charcoal. This study demonstrated that bamboo charcoal could be used for the removal of Cd (II) ions in water treatment.
In this work, the adsorption potential of bamboo waste based granular activated carbon (BGAC) to remove C.I. Reactive Black (RB5) from aqueous solution was investigated using fixed-bed adsorption ...column. The effects of inlet RB5 concentration (50–200
mg/L), feed flow rate (10–30
mL/min) and activated carbon bed height (40–80
mm) on the breakthrough characteristics of the adsorption system were determined. The highest bed capacity of 39.02
mg/g was obtained using 100
mg/L inlet dye concentration, 80
mm bed height and 10
mL/min flow rate. The adsorption data were fitted to three well-established fixed-bed adsorption models namely, Adam's–Bohart, Thomas and Yoon–Nelson models. The results fitted well to the Thomas and Yoon–Nelson models with coefficients of correlation
R
2
≥
0.93 at different conditions. The BGAC was shown to be suitable adsorbent for adsorption of RB5 using fixed-bed adsorption column.
Ash fusion characteristics of bamboo, masson pine and coal were investigated using X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron ...microscopy (TEM). XRF results showed that the major components of bamboo ash were K2O, SiO2 and SO3. Masson pine ash mainly included Fe2O3 and CaO. Coal ash was comprised of SiO2, Al2O3, CaO, Fe2O3 and SO3. The variation of major components resulted in different fusion characteristics, such as the low fusion temperature of bamboo ash and the high thermal conductivity of masson pine ash. XRD results confirmed chemical compositions transformation because six main chemical reactions occurred during thermal treatment process. SEM and TEM results showed that the elongated grains or plates of various sizes of all thermal treated ashes disappeared and they had less pores and denser structure on the surface, indicating structure transformation. The results from this research will be helpful to promote utilization of masson pine and bamboo for fuel in power station of China.
•Each ashes have different major components.•Bamboo ash has the lowest fusion temperature.•There are six chemical reactions during tranformation process.•The elongated grains or plates of treated ashes disappear.•Treated ashes have less pores and denser structure.
•Slow pyrolysis of bamboo was conducted by TG-FTIR-GCMS.•FTIR indicated functional group emission such as H2O, CH4, CO2, CO, and CO.•CO2 and acids are main composition of evolved gas during bamboo ...pyrolysis.•Slow pyrolysis mechanism at different temperature stages was established.
Slow pyrolysis of bamboo is an important conversion pathway to produce biofuels and chemicals such as biomass-derived fertilizer precursor (biochar). In this study, evolved gas analysis during pyrolysis of bamboo was conducted by a combination of TG, FTIR and GC–MS to establish a detailed pyrolysis mechanism of bamboo biomass. The main decomposition temperature zones were 300–400 °C and it reached the maximum mass loss intensity at 350 °C based on DTG curves. The main functional groups escaped from biomass during pyrolysis were –OH, –CH2, –CH3, CO, C–O, and –COOH. The main compounds during pyrolysis of bamboo were acetic acid and 2-propenoic acid, ethenyl ester at 300 °C, 2-oxo-propanoic acid and 1-hydroxy-2-propanone at 350 °C and acetic acid and acetic acid ethenyl ester at 400 °C. Evolved gas analysis indicated that components in bamboo occurred in different temperatures and pyrolysis mechanisms and resulted in distinguishing pyrolysis product emission characteristics.
•A fast and efficient delignification was achieved by formic acid under pressure.•High pressure system accelerates the cleavage of β-O-4′, β-β, and β-5′ in lignin.•Delignification and condensation ...reaction occurred simultaneously.•Higher phenolic hydroxyl and carboxyl group contents of lignin could be achieved.
Bamboo was fractionated using formic acid based on a one-step organosolv process under high pressure (at 145°C for 45min, 0.3MPa) and at atmospheric pressure (at 101°C for 120min), respectively. High-pressure formic acid lignin, atmospheric formic acid lignin and milled wood lignin of bamboo were subjected to comprehensive structural characterization using gel permeation chromatography (GPC), Fourier transform infrared (FTIR) and solution-state NMR techniques (1H, 13C, 2D-HSQC, and 31P-NMR spectroscopies). The results indicated that the formic acid fractionation under high pressure presents a quick and efficient delignification method by enhancing the cleavage of interunitary bonds in lignin (β-O-4′, β-β and β-5′), and dissolved lignin also occurred condensation reaction. As compared to atmospheric formic acid lignin, high-pressure formic acid lignin obtained showed higher purity and yield, and had relatively higher contents of phenolic and carboxylic groups.
This review deals with a recent study of the literature on the various aspects of cellulosic fibres and biocomposites. Cellulosic fibre reinforced polymeric composites are finding applications in ...many fields ranging from construction industry to automotive industry. The pros and cons of using these fibres are enumerated in this review. The classification of composites into green composites, hybrid biocomposites and textile biocomposites are discussed. New developments dealing with cellulose based nanocomposites and electrospinning of nanofibres have also been presented. Recent studies pertaining to the above topics have also been cited. Finally, the applications of cellulosic fibre reinforced polymeric composites have been highlighted.
Bamboo was converted into carbon fibre using a novel approach combining microwave pyrolysis, solvent extraction, and chemical impregnation. The employment of solvent extraction and chemical ...impregnation transformed natural bamboo into bamboo fibre with yield of 64 wt% that comprised of 87 wt% cellulose, 4 wt% lignin and 9 wt% hemicellulose deemed desirable for conversion into carbon fibre. The subsequent use of microwave pyrolysis transformed the bamboo fibre to form carbon fibre; the effects of microwave irradiation time and microwave power (two key process parameters) on properties of carbon fibre were investigated. Microwave pyrolysis provides a rapid heating rate (30 °C/min) with relatively shorter process time (20 min) compared to that performed by conventional pyrolysis method, thus leading to a relatively lower electric consumption and providing a potentially cost-saving and energy-efficient approach to produce carbon fibre. The production and properties of carbon fibre produced were affected by irradiation time and microwave power. The carbon fibre obtained was detected to have high fixed carbon (80 wt%), carbon element (87%), high BET surface area (475 m2/g) and fibres in small diameter (≤1 μm). It also shows desirable features comprising low content of moisture (<6 wt%), inorganic elements of Na, K, S, Mg (≤5%) and ash (1 wt%), allowing the carbon fibre to have more active sites and making it a cleaner product rather than polluting the environment whereas a high ash content could lead to undesired catalytic reactions and emission of potentially hazardous metallic components present in the ash. Combined with the detection of positive capacitive behaviour, the carbon fibre shows great potential to be used as an electrode for energy storage application. The results disclose that microwave pyrolysis combining with solvent extraction and chemical impregnation can be a cleaner approach to transform bamboo into carbon fibre with favourable physicochemical and capacitive properties.
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•A new approach combining microwave pyrolysis, solvent extraction, impregnation.•The microwave pyrolysis provides fast heating rate and a short process time.•Carbon fibre with favourable physicochemical and capacitive properties is obtained.•Carbon fibre has high fixed carbon, surface area, and small fibres.•Carbon fibre shows positive capacitive behaviour.
Studying the hygroscopic behavior of bamboo is important for industrial applications because it influences the dimensional stability and mechanical properties of the final bamboo products. In this ...study, the water vapor sorption behavior of 14 bamboo species was investigated using a dynamic vapor sorption apparatus and the results were analyzed using the Guggenheim–Anderson–de Boer (GAB) and Hailwood–Horrobin (H–H) models. The different bamboo species exhibited varying sorption isotherms and degrees of hysteresis. The reasons for this may be related to the different sorption isotherms of the two main cell units of bamboo, namely the fiber and parenchyma cells, and the chemical composition of bamboo. The GAB and H–H models provided good fits to the experimental data and meaningful physical parameters regarding the monolayer capacity, especially the water accessible specific surface area can be obtained from the GAB parameters. The fiber saturation point values were also determined using the GAB and H–H models, which ranged from 16.37 to 27.91% for the different bamboo species.
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•The biochar was prepared by ZnCl2 chemical activation and further HNO3 oxidation.•The biochar is rich in micropore.•The graphitization degree and surface acidic groups can improve ...its ADS performance.•The biochar has a good recycling performance.
In this work a series of bamboo-derived biochars rich in micropores (its micropore ratio as high as 76%) were prepared by ZnCl2 chemical activation of bamboo processing residues, further modified with oxidation using concentrated HNO3, and characterized by N2 adsorption, XRD, Raman spectra, elemental analysis and Boehm titration. Their adsorptive desulfurization (ADS) performances were examined using dibenzothiophene from model fuels as an adsorbate. The results showed that the pore structure properties of these biochars are dominated by ZnCl2 chemical activation, the graphitization degrees are mainly governed by activation temperature, and the significantly increased surface acidic groups are primarily contributed from the HNO3 oxidation treatment. The biochar’s abundant micropore characteristic is an indispensable prerequisite for its good ADS performance, and also its high graphitization degree and surface acidic groups play important roles in improving ADS performance. Meanwhile, the optimized biochar can achieve an sulfur removal (%) of 96% with a selectivity close to 96%, its maximum adsorption amount and its breakthrough capacity reach 38.4mg-S/g and 9.5mg-S/g, respectively, and it shows much superior ADS performance to commercial activated carbon (AC) used in this work. Furthermore, the biochar can be reused for three times after regeneration without significant loss of ADS capacity. Thus, the biochar may become an excellent ADS adsorbent for production of clean fuel oils.
