A facile, green and economical method for the high-efficiency utilization and functionalization of bamboo fiber could significantly improve the development of biomass industries. Here, we ...demonstrated a deep eutectic solvent, which formed from choline chloride (ChCl) and lactic acid (LC), as pretreating agent to delignify moso bamboo (
Phyllostachys pubescens
) and produce nanocellulose. The results showed that most of the lignin was efficiently removed (94.39%) and 91% of the cellulose was recovered after the moso bamboo was pretreated with ChCl–LC at 120 °C for 3 h with a solid-to-liquid ratio of 1:25. Furthermore, nanofibers with widths of 20–80 nm were successfully prepared from pretreated fibers after a simple mechanical process. SEM and AFM images showed that they have excellent aspect ratio. In addition, the obtained nanofibers could be used to fabricate strong films which feature a high tensile strength ranged from 163 to 213 MPa.
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•Hydrothermal carbonization and coupling washing with torrefaction were evaluated.•Biofuels with high fuel quality were generated from HTC and CWT processes.•HTC and CWT processes ...both improved the combustion behavior of biofuels.•Slagging and fouling index for biofuels after pretreatment was obviously improved.
Two kinds of biofuels were produced and compared from hydrothermal carbonization (HTC) and coupling washing with torrefaction (CWT) processes of bamboo sawdust in this study. The mass and energy yields, mass energy density, fuel properties, structural characterizations, combustion behavior and ash behavior during combustion process were investigated. Significant increases in the carbon contents resulted in the improvement of mass energy density and fuel properties of biofuels obtained. Both HTC and CWT improved the safety of the biofuels during the process of handling, storing and transportation. The ash-related issues of the biofuels were significantly mitigated and combustion behavior was remarkably improved after HTC and CWT processes of bamboo sawdust. In general, both HTC and CWT processes are suitable to produce biofuels with high fuel quality from bamboo sawdust.
•Potassium-sodium geopolymer is reinforced with bamboo fibers and strips.•Testing the geopolymer-bamboo composite yielded good to high flexural strength.•SEM micrographs reviewed the interface ...between the fibers and the geopolymer matrix.•Metakaolin geopolymer was cured at 50°C for 24h and set to dry for 7days at room temperature.•Room temperature cure was also achievable with the same system.
In the pursuit of sustainable construction, regional natural materials can be used as a base for geopolymer processing. For higher strength achievement, this study uses mixed potassium-sodium polysialate siloxo-type geopolymer reinforced with bamboo fibers and strips. The composite geopolymer reinforced with bamboo fibers was used as a binder for the bamboo strips. Geopolymer was synthesized using metakaolin produced from kaolinite extracted from Amazonian soil, and microscopically compared to a commercial, highly reactive, Metamax metakaolin-based geopolymer. Amazonian kaolin was converted into metakaolin by calcination up to 700°C. X-ray diffraction (XRD) analysis showed the resulting amorphous metakaolin to be 76% pure, with 24% crystalline quartz impurity. Four-point flexural and compressive strength testing of the geopolymer were carried out according to ASTM standards C1341-13 and C1424-10. Scanning electron microscopy (SEM) was used to investigate the microstructure and the interface. In addition, XRD was used to confirm the formation of geopolymer. Amazonian metakaolin geopolymer reinforced with bamboo is a potential green sustainable construction material with compressive strength ranging from: 23–38MPa for micro bamboo fibers alkali treated (BF1A), 23–25MPa for short BF alkali treated (BF4A), and 25–29MPa for short BF water treated (BF4W). Flexural strength values for geopolymer reinforced with bamboo fibers ranged from: 4–8MPa for BF1A, 7–8MPa for BF4W, and reached 21–30MPa for mixed BF1A and bamboo strip reinforcements.
•The protonated amine modified hydrochar was synthesized for anionic dye removal.•The protonated amine groups play a key role on sorption of MO by PAMH.•The electrostatic interaction is the main ...mechanism.•The modified hydrochar can remove efficiently MO from aqueous solution.
The protonated amine modified hydrochar (PAMH) was synthesized by etherification, amination and protonated reaction with hydrochar, which was enriched with abundant protonated amine for methyl orange (MO) removal. PAMH was characterized by elemental analysis, scanning electron microscopy, nitrogen adsorption-desorption measurement, zeta potential and Fourier transform infrared. The sorption of MO from aqueous solution by PAMH was investigated by batch experiments. The results showed that sorption of MO was significantly influenced by the initial concentration of MO, temperature, contact time and ionic strength, while hardly affected by pH values ranging from 4 to 11. The pseudo-second-order and Langmuir equations were able to depict sorption kinetics and sorption isotherms, respectively. Thermodynamic analysis indicated that the sorption behavior was thermopositive and spontaneous. The maximum theoretical uptake computed by the Langmuir equation was 909.09 mg·g−1 at 303 K, which suggested that PAMH was an effective sorbent to eliminate anionic dye from aqueous solution.
Resumo O presente estudo trata do levantamento florístico das espécies de Bambusoideae (Poaceae) que ocorrem no Parque Estadual da Serra do Brigadeiro (PESB), Minas Gerais, Brasil. O domínio ...fitogeográfico em que a área de estudo está inserida é a Floresta Atlântica, considerada um dos centros de endemismo de bambus. Foram realizadas expedições de agosto de 2013 a julho de 2015 para a coleta do material botânico e observação das espécies no seu ambiente natural. Além disso, foram analisadas as coleções dos herbários BHCB, CESJ, HUEFS, ISC, K, MG, RB, SPF, VIC e VIES. Foram registradas 27 espécies pertencentes a seis gêneros. O gênero com maior número de espécies é Chusquea, com 16 espécies, seguido de Merostachys e Aulonemia, com quatro espécies cada, e Colanthelia, Guadua e Parodiolyra com uma espécie cada. São apresentadas chaves de identificação para os gêneros e as espécies, descrições e comentários morfológicos. O PESB apresenta a maior riqueza de espécies de bambus já registrada nas unidades de conservação de Minas Gerais.
Abstract This study consists of a floristic survey of the Bambusoideae (Poaceae) species that occur in the Serra do Brigadeiro State Park (PESB). The study area is inserted in the Atlantic Forest, considered as one of the centers of bamboo endemism. We carried out expeditions from August 2013 to July 2015 for the collection of botanical material and observation of the species in their natural environment. In addition, the collections of the herbaria BHCB, CESJ, HUEFS, ISC, K, MG, RB, SPF, VIC, and VIES were analyzed. Six genera and 27 species were recorded in the PESB. The most diverse genus is Chusquea with 16 species, followed by Merostachys and Aulonemia with four species each, and Colanthelia, Guadua, and Parodiolyra with one species each. Identification keys for genera and species, descriptions, and morphological comments are presented. PESB has the highest bamboo species richness recorded for the conservation units of Minas Gerais.
•Bamboo chips were efficiently fractionated using a combined fractionation process.•The production of cellulose pulp, lignin, and oligosaccharides was achieved.•The major linkages of side-chain in ...lignin were cleaved during the integrated process.•This process can produce lignin with high purity and high chemical reactivity.•The combined process presented the advantage of economic feasibility of biorefinery.
Bamboo chips were efficiently fractionated using an integrated process of autohydrolysis and formic acid to induce rapid delignification. Autohydrolysis pretreatment facilitated oligosaccharide production, while the subsequent rapid-delignification using formic acid at a low liquid/solid ratio with a relatively short reaction time allowed obtaining cellulose fibers and lignin. The major inter-unit linkages of side-chain in lignin were cleaved during the combined fractionation process. The lignin fraction exhibited higher purity, more phenolic OH groups, less condensed phenolic OH groups, and higher syringyl/guaiacyl ratio (S/G) as compared to MWL and formic acid lignin from the direct formic acid delignification. These results indicate that the combined fractionation process presents a promising approach to the commercial utilization in the biorefinery industry.
In this work, a novel, simple, economical and green carbon quantum dots (CQDs) were obtained by hydrothermal method using bamboo as a carbon source at the first time. In order to further the use of ...such CQDs, we reported the facile fabrication of CQDs/Bi3Ti4O12 (BTO) nanosheets photocatalysts. The experimental results indicated that CQDs were successfully coupled with BTO nanosheets, exhibiting excellent photocatalytic activity than bare BTO. The improved photodegradation efficiency was attributed to the extended light absorption range, and increased separation rate of electron-holes pairs. At last, a possible photocatalytic mechanism was proposed. The design of such CQDs from the creature with semiconductor can be extended to photocatalytic systems.
•Bamboo as raw material for carbon quantum dots (CQDs).•The CQDs were coupled with Bi3Ti4O12 nanosheets have exhibited excellent photocatalytic activity.•The CQDs has superior electron transfer ability and enriched light harvesting.
•Sequential alkali extraction-AHP treatment enabled efficient bamboo fractionation.•The proposed process produces ethanol and recovers lignin and silica.•Compared to traditional one-stage AHP, H2O2 ...demand could be substantially lowered.•High ethanol titer was reached with relatively low enzyme loadings.
A sequential two-stage pretreatment process comprising alkaline pre-extraction and alkaline hydrogen peroxide pretreatment (AHP) was investigated to convert bamboo carbohydrates into bioethanol. The results showed that mild alkaline pre-extraction using 8% (w/w) sodium hydroxide (NaOH) at 100°C for 180min followed by AHP pretreatment with 4% (w/w) hydrogen peroxide (H2O2) was sufficient to generate a substrate that could be efficiently digested with low enzyme loadings. Moreover, alkali pre-extraction enabled the use of lower H2O2 charges in AHP treatment. Two-stage pretreatment followed by enzymatic hydrolysis with only 9FPU/g cellulose led to the recovery of 87% of the original sugars in the raw feedstock. The use of the pentose-hexose fermenting Saccharomyces cerevisiae SR8u strain enabled the utilization of 95.7% sugars in the hydrolysate to reach 4.6%w/v ethanol titer. The overall process also enabled the recovery of 62.9% lignin and 93.8% silica at high levels of purity.
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.
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