•Slow pyrolysis of bamboo was conducted at pyrolysis temperature of 400–600 °C.•Biochar at 600 °C had good physiochemical properties than biochar at 400 and 500 °C.•Biochar yield was predicted based ...on carbonization index of biomass components.•Pathways of cellulose, hemicellulose and lignin to biochar was established.
Slow pyrolysis of bamboo was conducted at 400–600 °C and pyrolysis products were characterized with FTIR, BET, XRD, SEM, EDS and GC to establish a pyrolysis product yield prediction model and biochar formation mechanism. Pyrolysis biochar yield was predicted based on content of cellulose, hemicellulose and lignin in biomass with their carbonization index of 0.20, 0.35 and 0.45. The formation mechanism of porous structure in pyrolysis biochar was established based on its physicochemical property evolution and emission characteristics of pyrolysis gas. The main components (cellulose, hemicellulose and lignin) had different pyrolysis or chemical reaction pathways to biochar. Lignin had higher aromatic structure, which resulted higher biochar yield. It was the main biochar precursor during biomass pyrolysis. Cellulose was likely to improve porous structure of pyrolysis biochar due to its high mass loss percentage. Higher pyrolysis temperatures (600 °C) promoted inter- and intra-molecular condensation reactions and aromaticity in biochar.
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•Activated biomass carbon (ABC) produced from bamboo was prepared by carbonization and KOH activation.•The BET and morphology of the ABC have a strong dependence on the activation ...temperature.•High specific capacitance along with durability is achieved.•Activated biomass carbon can serve as efficient electrode material for energy storage.
Activated biomass carbons (ABC) produced from bamboo by carbonization and activation have high specific surface areas and mesoporous structures. The specific surface area, total pore volume, and average pore size of the activated biomass carbon are controlled by adjusting the activation temperature from 700 to 1000 °C. The carbon materials activated at 900 °C have an optimal mesoporous structure with a high specific surface area (2221.1 m2 g−1), the highest capacitance (293 F g−1 at 0.5 A g−1 in 3 M KOH aqueous electrolyte) and excellent rate capability (193.8 F g−1 at 20 A g−1). Symmetric supercapacitors made of the optimal electrodes exhibit a high energy density of 10.9 Wh kg−1 (18.2 Wh L−1) at a power density of 63 W kg−1 (105 W L−1) and outstanding capacitance retention of 91.8% over 10,000 cycles. The high electrochemical performance of the mesoporous ABCs show that they are highly promising for energy-storage applications with further optimization.
The cleaner production of environmentally friendly materials for the controlled adsorption and desorption of ammonium and phosphate in wastewater treatment and soil fertility maintenance is a ...challenge. Here we show that a class of clay mineral-biochar composites which were produced via a facile cleaner pyrolysis process starting from two abundant natural materials (montmorillonite and bamboo powder). The montmorillonite-biochar composites (MBC) were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, N2 adsorption/desorption isotherms, thermogravimetric analysis, and scanning electron microscopy. The adsorption and slow-release characteristics of MBC samples for NH4+ and PO43− in aqueous solution were evaluated. Montmorillonite (Mt) acted as a solid acidic catalyst and catalyzed the pyrolysis of bamboo powder to biochar and lower the pyrolysis temperatures. Both biochar and Mt contributed to the texture and structure, which provided varied surface and various adsorptive sites. The Langmuir maximum adsorption capacity of MBC samples for NH4+ and PO43− was 12.52 mg·g−1 and 105.28 mg·g−1. The adsorption of NH4+ onto the MBC sample was primarily controlled by surface adsorption and partially by a CEC process. The adsorption capacity of PO43− resulted from the electrostatic attraction or ionic bonding between PO43− and cations in the MBC samples such as Ca2+, Mg2+, Al3+ and Fe3+. The release of NH4+ and PO43− from the NH4+- and PO43−-laden MBC samples was merely 0.30–4.92% and 2.63–5.09% within 2–88 h. These findings implied that the MBC samples prepared from low-cost Mt and bamboo can remove NH4+ and PO43− from aqueous solution by adsorption and the resultant NH4+- and PO43−-laden MBC samples can be used as an effective slow-release fertilizer of N and P.
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•Pyrolyzing bamboo with montmorillonite (Mt) yields Mt-biochar composite (MBC).•Further to being an adsorbent, Mt also plays a catalytic role in pyrolysis of bamboo.•MBC has good adsorptive capacity for NH4+ and PO43−.•Adsorption of NH4+ and PO43− are controlled by different mechanisms.•NH4+- and PO43−-laden MBC exhibit slow-release behaviors.
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•The well aligned bamboo fibers structure is retained in the resulting composites.•A 236% increase in tensile strength is observed for epoxy/bamboo composite.•Epoxy/bamboo composite ...shows a high specific strength (145 MPa·cm3/g).•Simultaneous improvement in strength and toughness of the composite was achieved.
Herein we reported a simple and effective approach to processing bulk natural bamboo directly into a high-performance composite material with high tensile strength, modulus and toughness. Our two-step approach involved the removal of lignin from natural bamboo followed by epoxy infiltration, leading to the complete filling of epoxy into the porous structure of the delignified bamboo with highly aligned cellulose fibers. In contrast to the bulk natural bamboo and the delignified bamboo, the epoxy infiltrated bamboo composite displayed higher dimensional stability against moisture. Furthermore, the as-prepared epoxy infiltrated bamboo composite showed 236% and 136% increase in tensile strength and impact strength, respectively, as compared to the bulk natural bamboo. The simultaneous improvement in strength and toughness makes the epoxy infiltrated bamboo composite highly desirable for structural material applications.
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•Highly microporous Fe3O4–BB was prepared from Moso bamboo.•Persulfate oxidation processes are proposed for the degradation of 4-NP in real river sediments.•4-NP degradation rate ...depends on pH value and Fe3O4–BB dose.•The Kobs of 4-NP degradation followed the order: Fe3O4–BB/PS ˃ PS ˃ Fe3O4–BB.•The Langmuir-Hinshelwood model was found to fit the kinetic equation.
In this study, an environmentally friendly and economically viable bamboo biochar (BB) was modified by Fe3O4 and was applied for the treatment of real river sediments containing the endocrine disruptor chemical (EDC) 4-nonylphenol (4-NP). The microporosity of Fe3O4–BB was clearly observed from the N2 adsorption isotherms. The catalytic performance of Fe3O4–BB is highly dependent on pH and the catalyst dosage. The degradation efficiency of 4-NP (85%) was achieved at pH 3.0 using an initial dosage of 3.33 g L−1 Fe3O4–BB and 2.3 × 10−5 M persulfate (PS) in a biochar–sediment system. The kinetic behavior of 4-NP degradation with catalysis can be accounted by using the Langmuir-Hinshelwood type kinetic model. The MTT assay results indicated that Fe3O4–BB has a low potent cytotoxic effect and is therefore suitable for application in remediation of contaminated sediment.
•The hydrothermal carbonization of bamboo, PVC and their mixture were studied.•The complex synergistic effect occurred during co-hydrothermal carbonization.•The dechlorination efficiency of the PVC ...and mixture were studied.•The combustion performance of hydrochars were detected.
The PVC waste and bamboo were treated by co-hydrothermal carbonization (co-HTC) at three different temperatures. The inorganic-Cl could be removed from the carbon rich solid products (hydrochar) in the form of HCl via hydrolysis, elimination, substitution and aromatization. Due to the high carbon content, the hydrochar could be applied as premium fuel. Bamboo had a synergistic effect on dechlorination with PVC in the HTC process. The bamboo could accelerate the HTC dechlorination of PVC at 200°C because it strengthened the substitution of Cl with OH. While at 230 and 260°C, the existence of bamboo hindered the dechlorination of PVC in HTC. Thermogravimetric analysis showed the combustion performance of hydrochar was better than the raw samples at 200°C. Owing to the low chlorine content, low ignition temperature and the superior combustion performance, the M-260 can be adopted as alternative fuels for coal.
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•The first example of reductive catalytic fractionation of bamboo was illustrated.•High yields of monophenols were preferentially produced from lignin depolymerization.•RCF process ...allowed the well-preservation of carbohydrate component.•(Hemi)cellulose pulp obtained from RCF process is amenable to enzymatic hydrolysis.
Reductive catalytic fractionation (RCF) has emerged as a new biorefinery paradigm for the fractionation and sequential utilization of entire components of biomass. Herein, we investigated the RCF of bamboo, a highly abundant herbaceous feedstock, in the presence of Pd/C catalyst. The lignin fraction in bamboo was preferentially depolymerized into well-defined low-molecular-weight phenols, with leaving carbohydrates pulp as a solid residue. In the soluble fraction, four major phenolic compounds, e.g., methyl coumarate/ferulate derived from hydroxycinnamic units and propanol guaiacol/syringol derived from β-O-4 units, were generated up to 41.7 wt% yield based on original lignin content. In the insoluble fraction, the carbohydrates of bamboo were recovered with high retentions of cellulose (68%) and hemicellulose (49%), which upon treatment with enzyme gave glucose (90%) and xylose (85%). Overall, the three major components of bamboo could efficient to be fractionated and converted into useful platform chemicals on the basis of this study.
Background: Bamboo is a multipurpose plant known mostly for its industrial uses but is now being recognized as a potential source of bioactive compounds and natural antioxidants. All the parts of the ...bamboo plant such as rhizome, culm shaving, leaves, roots, shoots and seeds have clinical applications. Studies have revealed that bamboo is a rich source of antioxidants and regular consumption of bamboo-based products may reduce the risk of age-related chronic diseases including cardiovascular diseases, Alzheimer's disease, Parkinson's disease, cancer and diabetes.
Scope and approach: This review article reports a comprehensive insight concerning antioxidants and antioxidant properties of bamboo shoots and leaves and their prospects for utilization in the development of functional foods and nutraceuticals. Antioxidants are vital constituents in the food and pharmaceutical industry as they scavenge free radicals that cause deterioration of products during processing and storage. They also promote human health by neutralizing cell damage caused by free radicals.
Key findings and conclusion: Antioxidants are known to confer health benefits such as prevention of cancer and degenerative diseases, slowing down the aging process and promotion of cardiovascular health. The main antioxidants in bamboo leaves and shoots are phenols, vitamin C & E and mineral elements such as selenium, copper, zinc, iron and manganese. At present, natural antioxidants are in great demand as synthetic antioxidants being used in food and pharmaceuticals may be deleterious to health. Hence, bamboo a fast growing plant with huge biomass can serve as an alternative for the production of natural antioxidants.
•Bamboo is a rich source of nutrients, bioactive compounds and antioxidants.•Phenols, flavonoids, vitamin C and E are the dominant antioxidants in bamboo shoots.•Selenium, zinc, copper, iron and manganese present in bamboo shoots mediate vital biochemical reactions.•Antioxidant compounds in bamboo can be a natural alternative for the development of functional food and nutraceuticals.
The Northeastern hilly states of India harbor nearly 90 species of bamboos, 41 of which are endemic to the region. Estimation of C-storage and C-sequestration in aboveground biomass of two common ...bamboo species namely Bambusa tulda and Dendrocalamus longispathus was carried out in Mizoram-one of the eight states of Northeastern India. Recording of density of culms was done by quadrate method and harvesting of culms was done to estimate the aboveground biomass. C-storage in different components of the culms was found out for three age classes namely 1, 2 and ≥ 3 year old culms. Aboveground biomass ranged from 73.58 to 127 Mg/ha in Bambusa tulda and 115 to 150 Mg/ha in Dendrocalamus longispathus. Culm density and aboveground biomass were maximum in the ≥ 3 year age class in both the species. C-storage ranged from 36.34 to 64.00 Mg/ha in Bambusa tulda and 50.11 to 65.16 Mg/ha in Dendrocalamus longispathus. Although having lower aboveground biomass the rate of C-sequestration was higher in Bambusa tulda with 27.79 Mg/ha/year than Dendrocalamus longispathus which have 15.36 Mg/ha/year. The reason was attributed to higher increment of culm density and DBH of the older age class in the second year study period in Bambusa tulda.
Walter Liese, 1926-2023 Katarina Čufar
Les (Ljubljana, Online),
12/2023, Volume:
72, Issue:
2
Journal Article
Peer reviewed
Open access
Prof. dr. dr. h. c. mult. Walter Liese (1926–2023) je bil vodilni znanstvenik, učitelj, mentor, direktor, vodja, predsednik IUFRO, večkratni častni doktor in ambasador znanosti na področju gozdarstva ...in lesarstva. Po diplomi in doktoratu iz gozdarstva je opravil pionirsko in izjemno življenjsko delo na področju elektronske mikroskopije ter biologije in zaščite lesa ter bambusa. V obdobju 1963–1991 je deloval kot profesor na Univerzi v Hamburgu, vodja inštituta za Biologijo in zaščito lesa in direktor Zveznega raziskovalnega centra za gozdarstvo in lesarstvo. Njegovo delo je imelo izjemen vpliv na razvoj znanosti in laboratoriji, ki jih je vodil, so bili referenčna točka za znanost o lesu in bambusu na svetu. Bil je aktiven član svetovne organizacije IUFRO in v letih 1977–1981 njen predsednik ter izjemen ambasador znanosti in povezovalec. Vsestransko je podpiral znanstveno skupnost v Sloveniji. Leta 1994 je kot prvi znanstvenik s področja gozdarstva in lesarstva prejel častni doktorat Univerze v Ljubljani. Tudi po uradni upokojitvi je nadaljeval z raziskovalnim delom in ostal povezan s svetovno znanstveno skupnostjo.
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