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To evaluate the combustion characteristics of raw or torrefied bamboo wastes and coal blends, the co-firing process determined by cone and pollutant emission was investigated by thermogravimetric analysis coupled with Fourier transform infrared spectroscopy. The results showed that torrefaction improved the fuel properties of bamboo wastes. Torrefied bamboo had a lower volatile fuel ratio, H/C and O/C ratios, pollutant emission and a higher heating value. They further affected the co-firing process of raw or torrefied bamboo and coal. All blends had a lower ignition temperature and a more stable flame than coal. Torrefied bamboo and coal blends had a lower percentage of quality loss, a higher heat release rate (HRR), total heat release (THR) and total smoke release (TSR). With an increase in the proportion of torrefied bamboo in the blends, the HRR, THR, TSR and percentage of quality loss increased. The main pollutant emissions included CO2, CO, SO2 and NO x. All blends of torrefied bamboo and coal had a lower pollutant emission. The optimum blend suggested was 20% torrefied bamboo/80% coal.

N-doped porous carbon materials derived from bamboo fibers (NBFCs) were synthesized through a simple simultaneous activation and carbonization method. The effects of the adsorbent dosage, absorption temperature, pH of the solution, initial concentration, and contact time on the absorption of methylene blue were investigated. The equilibrium, kinetics, isotherms, and thermodynamics of the adsorption process were also analyzed. The results showed that NBFC-800 had a good adsorption capacity of 816.0 mg/g and a high removal efficiency of 93.3% during the optimum absorption process with an adsorbent dosage of 0.8 g/L, adsorption temperature of 25 °C, initial concentration of 700 mg/L, and a solution pH of 9.0. The adsorption process included instantaneous adsorption or external surface adsorption, intraparticle diffusion, and an equilibrium process. Methylene blue adsorption of NBFC-800 agreed with the pseudo second-order model and belonged to the Langmuir isotherm model. The results will be useful for the development of high-performance NBFCs to efficiently remove methylene blue from wastewater.

Co-firing characteristics of masson pine and coal was determined using thermogravimetric analysis at different heat rates in an air atmosphere. The kinetic parameters were calculated using Kissinger-Akahira-Sunose and Coats-Redfern method. Pollutant emission and ash characteristics were also investigated. Results showed that all samples had two separated combustion zones during co-firing process except for coal, corresponding to volatile and char combustion. CO2 had the highest releases and SO2 had the lowest release. The chemical compositions and thermodynamic properties of blend ash were similar with coal ash. The optimum blend ratio was 20% masson pine and 80% coal because it had the similar kinetic parameters and ash characteristics with coal. Furthermore, it also had a lower pollutant emission. The results from this research will be helpful to develop masson pine as fuel products in China.

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.

This study was carried out to investigate pyrolysis characteristics of moso bamboo (Phyllostachys pubescens), including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), through TG-FTIR and Py-GC/MS. The results showed that 70% of weight loss occurred at rapid pyrolysis stage with temperature of 200-400 °C. With increase in heating rate, pyrolysis process shifted toward higher temperature. IB, OB, MB and BL had a different activation energy at different conversion rates. BL had a higher activation energy than IB, OB and MB. The volatiles of bamboo was complicated with 2-30 of C atoms. IB, OB and MB mainly released benzofuran, hydroxyacetaldehyde and 2-Pentanone. BL released furan, acetic acid and phenol. The main pyrolysis products included H2O, CH4, CO2, CO, carboxylic acids, NO, NO2. Pyrolysis products of IB was the most and that of BL was the lowest. MB had the lowest pyrolysis temperature.

To compare with pyrolysis characteristics of cellulose from moso bamboo and poplar, samples were pyrolyzed with different heating rates through thermogravimetric analysis (TG). The kinetics was calculated by Kissinger–Akahira–Sunose method. The results showed that pyrolysis process of moso bamboo and poplar fiber included three stages, and the main pyrolysis occurred in the second step. Moso bamboo fiber had a higher start temperature, a lower end temperature and a more mass loss at each heating rate in the main pyrolysis stage. With increase in heating rate, the temperature corresponding to the maximum of mass loss increased and the DTG curve shifted to higher temperature. The reaction rates varied at different heating rates. The activation energy of cellulose from moso bamboo was lower than poplar cellulose, indicating cellulose of moso bamboo was easier to be pyrolyzed. The results from this research will provide guidance to thermal conversion of moso bamboo and poplar.

Bamboo curtain and poplar veneers, which are used as decorative building materials, were impregnated using two types of fire retardants (A and B) at atmospheric pressure in order to investigate fire retardancy using a cone calorimeter. When the impregnation time was longer, the fire retardancy was enhanced in the decorative material samples. When poplar veneer was treated by fire retardant A with impregnation times of 8 h, 16 h, and 24 h, the peak of heat rate release (pk-HRR) decreased by 41%, 51%, and 50%; the total heat release (THR) values decreased by 61%, 69%, and 75%; the total suspended particulates (TSP) values decreased by 90%, 82%, and 72%; and mass residues increased by 39%, 41%, and 43%, respectively. Treated bamboo curtain veneer had a lower fire retardancy when compared to poplar veneer. When bamboo curtain impregnation times were 8 h, 16 h, and 24 h, their pk-HRR values decreased by 37%, 45%, and 51%; the THR values decreased by 32%, 39%, and 44%; the TSP values decreased by 69%, 57%, and 78%; and the mass residues increased by 26%, 28%, and 29%, respectively. The results from this research should help to develop bamboo curtain veneer as an indoor decorative material.

Bamboo and masson pine was torrefied with 300°C of temperature for 2.0h of residence time using GSL 1600X tube furnace in the argon atmosphere. Torrefied bamboo and masson pine particles were uniform mixed with different weight ratios. Pyrolysis and combustion characteristics were investigated through thermogravimetry (TGA). The results showed that pyrolysis and combustion process of all samples included three steps even though their characteristics were different. Torrefied biomass had a higher pyrolysis and combustion temperature, due to moisture and volatile removal and thermal decomposition of hemicelluloses, cellulose and lignin during torrefaction process. Torrefaction also increased high heating value, ash content and C/H and C/O ratio of biomass. The synergy of torrefied bamboo and torrefied mason pine was not found during pyrolysis and combustion process of blends. The results from this research will be very important and helpful to develop and utilize the wastes of masson pine and bamboo for energy products.

To investigate co-combustion behavior of bamboo/coal blends, thermogravimetric analysis (TGA) was used to determine combustion characteristics of bamboo, torrefied bamboo, coal and their respective blends with five mixing ratios and three air flows. The results indicated that torrefaction was an effective way to improve physical properties of bamboo materials. The combustion process of bamboo and torrefied bamboo included drying, oxidative pyrolysis and char combustion. Torrefied bamboo had a lower reactivity compared to bamboo. The ignition and burnout temperature of torrefied bamboo also shifted to higher temperature. The char combustion of torrefied bamboo and coal coincided. The presence of bamboo and torrefied bamboo improved the thermo-chemical reactivity of blends. Air flow could also enhance the combustion reaction and strengthen combustion efficiency of blends. It was better potential for the co-combustion of torrefied bamboo and coal blends in existing coal-fired power plants. The results from this research will be very important and helpful to promote bamboo resources as a blend fuel for co-firing application with coal.

To the best of our knowledge, there is the lack of sufficient information concerning bamboo pellets. In the preliminary research, bamboo pellets showed a low bulk density which could not meet requirement of Pellet Fuels Institute Standard Specification for Residential/Commercial Densified (PFI). To improve its bulk density, pellets were manufactured using mixtures of bamboo and pine particles and the properties were investigated. It was found that adding pine particles to bamboo particles was an effective way to improve bulk density of bamboo pellets. When adding 40% pine particles to bamboo particles, bulk density of pellets increased from 0.54 g/cm3 to 0.60 g/cm3, meeting grade requirement of PFI utility. Furthermore, length, diameter and inorganic ash of pellets were also improved. Fine contents of pellets decreased from premium grade to utility grade according to PFI standard. Net calorific value also slightly decreased but it could meet the requirement of DIN 51731 (>17,500 J/g). The effect of this interaction on bulk density, inorganic ash, Net calorific value, combustion rate and heat release rate were significant. The results from this research will be very helpful to develop bamboo pellets and provide guidelines for further research.

This study was carried out to investigate combustion characteristics of moso bamboo, including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), respectively. The results showed that combustion characteristics of moso bamboo were similar to other biomass materials. There were two separate peaks in the combustion process; the first peak corresponding to combustion of volatile matters and the second peak corresponding to combustion of biochar. Compared to OB, MB and IB, BL had a worse fuel quality with higher H/C and O/C value, N and S content, ash content and lower combustion efficiency. Furthermore, BL had a higher slagging index and MB had a higher fouling index. These combustion characteristics of bamboo should be taken into consideration to efficiently design and operate the combustion systems when directly used for fuel production.

Highly porous nitrogen-doped carbons derived from bamboo shoots (BSNCs) were prepared through an in-situ synthesis method. The results showed that BSNCs had a large specific surface area, a relatively high nitrogen content and hierarchically porous structures. The catalytic properties of BSNCs were evaluated based on Knoevenagel condensation and transesterification reactions. Deprotonated BSNC-700 exhibited high efficiency for the model reactions as a solid base catalyst, and the superior sample deprotonated in tBuOK solution with a concentration of 0.1 increased the conversion rate from 16.1% to 76.0% for Knoevenagel condensation. The two reactions proceeded smoothly in the presence of deprotonated BSNC-700. The results also showed that the catalyst could be recycled for several times for Knoevenagel condensation. The results from this research will provide a guideline to develop bamboo shoot as a precursor to fabricate a superb solid base catalyst.

To investigate co-combustion characteristics of bamboo and wood, moso bamboo and masson pine were torrefied and mixed with different blend ratios. The combustion process was examined by thermogravimetric analyzer (TGA). The results showed the combustion process of samples included volatile emission and oxidation combustion as well as char combustion. The main mass loss of biomass blends occurred at volatile emission and oxidation combustion stage, while that of torrefied biomass occurred at char combustion stage. With the increase of bamboo content, characteristic temperatures decreased. Compared with untreated biomass, torrefied biomass had a higher initial and burnout temperature. With the increase of heating rates, combustion process of samples shifted to higher temperatures. Compared with non-isothermal models, activation energy obtained from isothermal model was lower. The result is helpful to promote development of co-combustion of bamboo and masson pine wastes.

Bamboo materials with improved antibacterial performance based on ZnO and graphene oxide (GO) were fabricated by vacuum impregnation and hydrothermal strategies. The Zn2+ ions and GO nanosheets were firstly infiltrated into the bamboo structure, followed by dehydration and crystallization upon hydrothermal treatment, leading to the formation of ZnO/GO nanocomposites anchored in the bulk bamboo. The bamboo composites were characterized by several techniques including scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and X-ray diffraction (XRD), which confirmed the existence of GO and ZnO in the composites. Antibacterial performances of bamboo samples were evaluated by the bacteriostatic circle method. The introduction of ZnO/GO nanocomposites into bamboo yielded ZnO/GO/bamboo materials which exhibited significant antibacterial activity against Escherichia coli (E. coli, Gram-negative) and Bacillus subtilis (B. subtilis, Gram-positive) bacteria and high thermal stability. The antimicrobial bamboo would be expected to be a promising material for the application in the furniture, decoration, and construction industry.

Bamboo shoots, a promising renewable biomass, mainly consist of carbohydrates and other nitrogen-related compounds, such as proteins, amino acids and nucleotides. In this work, nitrogen self-doped activated carbons derived from bamboo shoots were prepared via a simultaneous carbonization and activation process. The adsorption properties of the prepared samples were evaluated by removing methylene blue from waste water. The factors that affect the adsorption process were examined, including initial concentration, contact time and pH of methylene blue solution. The resulting that BSNC-800-4 performed better in methylene blue removal from waste water, due to its high specific surface area (2270.9 m2 g&minus, 1), proper pore size (2.19 nm) and relatively high nitrogen content (1.06%). Its equilibrium data were well fitted to Langmuir isotherm model with a maximum monolayer adsorption capacity of 458 mg g&minus, 1 and a removal efficiency of 91.7% at methylene blue concentration of 500 mg L&minus, 1. The pseudo-second-order kinetic model could be used to accurately estimate the carbon material&rsquo, s (BSNC-800-4) adsorption process. The adsorption mechanism between methylene blue solution and BSNC-800-4 was controlled by film diffusion. This study provides an alternative way to develop nitrogen self-doped activated carbons to better meet the needs of the adsorption applications.