Bamboo Biochar Research Articles

Bamboo for producing charcoal and biochar for versatile applications.

Bamboo, the fastest-growing plant, has several unique characteristics that make it appropriate for diverse applications. It is low-cost, high-tensile, lightweight, flexible, durable, and capable of proliferating even in ineffectual areas (e.g., incline). This review discusses the unique properties of bamboo for making charcoal and biochar for diverse applications. To produce bamboo charcoal and biochar, this study reports on the pyrolysis process for the thermal degradation of organic materials in an oxygen-depleted atmosphere under a specific temperature. This is an alternative method for turning waste biomass into products with additional value, such as biochar. Due to various advantages, bamboo charcoal is preferred over regular charcoal as it has four times the absorption rate and ten times more surface area reported. According to the reports, the charcoal yield ranges from 24.60 to 74.27%. Bamboo chopsticks were the most useful source for producing charcoal, with a high yield of 74.27% at 300 °C in nitrogen, but the thorny bamboo species have a tremendous amount of minimal charcoal, i.e., 24.60%. The reported biochar from bamboo yield ranges from 32 to 80%. The most extensive biochar production is produced by the bamboo D. giganteus, which yields 80% biochar at 300 °C. Dry bamboo stalks at 400 °C produced 32% biochar. One of the sections highlights biochar as a sustainable solution for plastic trash management produced during the COVID-19 pandemic. Another section is dedicated to the knowledge enhancement about the broad application spectrum of the charcoal and biochar. The last section highlights the conclusions, future perspectives, and recommendations on the charcoal and biochar derived from bamboo.

Influence of Biochar and Biofertilizer Mixture on Coffea spp. Planted in an Agroforestry Ecosystem

Coffee (Coffea spp.) is considered as one of the high-value commercial crops of the world. The study assessed the growth of mature and fruiting coffee in an already-established agroforestry ecosystems amended with biofertilizer, biochar, and vermicompost mixture. Field experiments were conducted on three coffee farms within the provinces of Laguna and Batangas, Luzon Island, Philippines (coded as Sta. Maria (Laguna), Lipa1 and Lipa2 (Batangas) with treatments: control, MYKORICH® biofertilizer (MRICH), 15% bamboo biochar (BB) and MRICH+BB. All trees were applied with one kg vermicompost per tree during the start of the experiment applied at 3-4 in below the soil surface, half m away from the base of the tree. MRICH+BB consistently gave a high significant increase of 221% stem diameter increment in Sta. Maria and 214% in Lipa2 after six months to three years. In Lipa1, BB treatment gave the highest increment (20.75 mm). Soil in Sta. Maria gave the highest spore count (136 per 50 g soil) when treated with MRICH. MRICH also promoted the highest nitrogen-fixing bacterial count (15.43 CFU x 106) in Lipa2. Highest fruit yield was gathered from MRICH+BB in Sta. Maria (2,010 g per tree) and Lipa1 (1,640 g per tree) while MRICH in Lipa2 (1,390 g tree). Positive effect was also observed on soil physico-chemical characteristics (OM, N, P, K, CEC) when inoculated with either MRICH or MRICH+BB treatments. These findings can be of significance to develop a low-input sustainable system on agroforestry soils using combined biofertilizers, biochar and vermicompost.

Efficacy of Biochar-biofertilizer-vermicompost Treatment on Theobroma cacao and Rhizosphere Soil Microbial Population

The study investigated the effects of a novel biochar-biofertilizer-vermicompost formulation on the rhizosphere soil microbial community and growth of mature T. cacao trees planted in three farms in the provinces of Batangas (Lipa) and Laguna (Liliw and Magdalena), Philippines. Cacao trees were amended with MYKORICH® (MR) without or with 15% bamboo biochar (15% BB) and vermicompost. In the three years span of the experiment, stem diameter increments of BB-treated cacao in Magdalena and Lipa were 5% and 19% higher than the control (56.09 mm and 49.08 mm), respectively, whereas MR and MR + BB-treated trees in Liliw were 34-35% higher relative to control. Soil microbial analysis showed that mycorrhizal spore counts in BB-amended soils were 133% (Liliw), 262% (Magdalena) and 109% (Lipa) higher than the control. Nitrogen-fixing bacteria obtained from MR + BB-amended soils in Liliw were 216% higher than control, and 81% higher relative to control in BB-treated soils in Lipa. Soil nitrogen and potassium contents of the three cacao farms also improved by 26-85%. With the significant effect of bamboo biochar and mycorrhizal fertilizer, alone or in combination, on the growth of cacao, the microbial community and nutrient status of the cacao rhizosphere soil, this technology would be beneficial to cacao farmers and to almost all crops in an agroforest ecosystem.

Fabrication of Phytic Acid/Urea Co-Modified Bamboo Biochar and Its Application as Green Flame Retardant for Polylactic Acid Resins.

It is of great significance to develop green, sustainable additives to improve the thermal stability and flame retardancy of biopolymers. In this work, a synergistic modification of P/N elements to bamboo biochar (mBC) was successfully achieved by grafting a reaction of phytic acid and urea with preoxidized bamboo biochar. Fourier transform infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance and scanning electron microscope determinations of the mBC demonstrated a successive grafting of phytic acid and urea to the originally porous surface. The ground mBC was blended with polylactic acid (PLA) to prepare mBC/PLA composites by extrusion and hot pressing. Mechanical strength studies showed a compromise in rigidity, which might originate from the mBC overdose and its limited miscibility with the resin. The thermogravimetric results supported the fact that the enhancement of thermal stability and flame retardancy of the composites with the mBC dosage, which showed that the mBC dosage in the PLA composites was not only lower than that of the conventional flame retardants, but also outperformed the counterparts using BC modified by inorganic phosphoric acid and urea. The mBC was prone to accelerate the earlier decomposition of the composites (30 °C lower in decomposition) and generate a continuous, dense residual carbon layer, which provides an effective shield resisting the mass and heat transfer between the combustion area and the underlying composite matrix. Only 10 wt% of mBC dosage could achieve a V-0 rating (UL94) for the composite, with a higher limiting oxygen index up to 28.3% compared to 20.7% for that of the virgin PLA; the cone colorimetric results also suggested that the flame retardancy had been greatly improved for all composites. In this work, biobased P-/N-containing bamboo biochar would be expected as a nontoxic biochar-based flame retardant that serves as green filler in polymer composites.

Agronomic Potential of Avocado-Seed Biochar in Comparison with Other Locally Available Biochar Types: A First-Hand Report from Ethiopia

Biochar is a promising option for improving soil fertility and agricultural productivity. The potential of biochar for specific purposes depends on its physical and chemical characteristics. The avocado seed is widely available as a leftover after the fleshy part is used for food and as a byproduct of avocado-oil producing agro-industries in Ethiopia. Its potential as a biochar for an agronomic purpose has not been studied. The objective of this study was to compare the agronomic potential of avocado-seed biochar (ASB) type in comparison to other biochar types produced from locally available feedstocks at two selected pyrolysis temperatures (450 and 550°C). It was identified that on a mass-base, the produced biochar yields were in a range of 29.68 to 47.45%, higher for ASB pyrolyzed at 450°C. The scanned images of the biochar types showed a remarkable surface morphology for bamboo biochar (BB) and ASB. The bulk density of the biochars were in the range of 0.21 to 0.49 g/mL. The highest volatile matter was measured for BB-450°C, fixed carbon for BB-550°C, and ash content for BB-450°C. The mean pH values were in the range of 9.1 to 11.3. The ASB-450 and 550°C exhibited higher nutrient content. The highest cation exchange capacity (CEC) was recorded for ASB-450°C; organic carbon (OC) for corncob biochar (CCB) was followed by ASB-450 and 550°C. The calcium carbonate (CaCO3) content of ASB-550°C was the second-highest value next to coffee husk biochar (CHB). In this study, ASB and BB were found to have important qualities for improving degraded agricultural soils in terms of soil acidity, nutrient content, and soil fertility. Therefore, ASB-450°C and BB-450°C can be suggested to be promising candidates for reclaiming acid-soils and for improving nutrient-depleted infertile soils into agriculturally productive soils.

Biochar reduces uptake and accumulation of polycyclic aromatic hydrocarbons (PAHs) in winter wheat on a PAH-contaminated soil

Biochar has been used previously for remediation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils for years, which has achieved remarkable results in improving removal of soil PAHs and reducing PAHs uptake in crops. However, the underlying mechanism of biochar application in reducing the uptake and accumulation of PAHs in winter wheat remains unclear. Pot trials using PAHs-contaminated soils were conducted for whole plant growth period of winter wheat, which were amended with 2% (w/w) bamboo biochar (BB), coconut shell biochar (CB) and maize straw biochar (MSB) or not (CK). Compared with CK, application of the three types of biochar significantly (p < 0.01) reduced grain PAHs concentration, the total equivalent concentration (TEC) values and the incremental lifetime cancer risk (ILCR) of grain PAHs, indicating that application of biochar reduced the exposure risk of PAHs in wheat grain, especially for MSB. Consistently, application of the three types of biochar significantly (p < 0.05) reduced uptake and accumulation of PAHs in root and stem of wheat, which may be due to that application of biochar enhanced the degradation of PAHs in the rhizosphere soil. Compared with CK, application of the three types of biochar significantly (p < 0.05) reduced the concentration of PAHs in the rhizosphere soil by 15.9%, 26.1% and 33.7%, respectively. It was found that the degradation rate of HMW PAHs (high molecular weight PAHs, 5-6 ring PAHs) was significantly (p < 0.05) higher than that of LMW PAHs (low molecular weight PAHs, 2-4 ring PAHs) regardless of types of biochar used. Additionally, application of the three types of biochar significantly increased the relative abundance of dominant bacterial phyla and genera in soil. Redundancy analysis and correlation analysis results also showed that there was a strong correlation between the removal rate of PAHs and dominant bacteria in the rhizosphere soil. The present study indicated that biochar could reduce dietary risk of PAHs in wheat grains mainly by increasing the abundance of bacteria related to PAHs degradation, promoting the biodegradation of PAHs in the rhizosphere soil and consequently reducing PAHs uptake in wheat.

Nitrogen retention potentials of magnesium oxide- and sepiolite-modified biochars and their impacts on bacterial distribution under nitrogen fertilization

Mitigating the loss and negative impacts of reactive N from fertilized soils remains a global environmental challenge. To optimize N retention by biochar, bamboo and pig manure biochars were modified as MgO- and sepiolite-biochar composites and characterized. Novel soil application of the modified biochars and their raw forms were comparatively evaluated for N-retention in a fertilized soil leached for 90 days in a column experiment. Changes in N-cycling-related enzyme and bacterial structure were also reported after 90 days. Results revealed low leaching losses of NH4+, which reduced over time across all the treatments. However, while sole fertilizer (F) increased the initial and cumulative NO3− leached from the soil, the MgO-bamboo biochar (MgOBF) and sepiolite-bamboo biochar (SBF) treatments reduced leachate NO3− by 22.1 % and 10.5 % compared to raw bamboo biochar (BBF) treatment. However, 15.5 % more NO3− was leached from the MgO-pig manure biochar-treated soil (MgOPF) compared to its raw biochar treatment (PMBF) after 90 days. Dissolved organic N leached was reduced by 9.2 % and 0.5 % in MgOBF and SBF, as well as 15.4 % and 40.5 % in MgOPF and SPF compared to their respective raw forms. The total N of the biochars, adjustment of surface charges, cation exchange capacity, surface area, pore filling effects, and the formation of potential MgN precipitates on the modified-biochar surfaces regulated N leaching/retention. In addition, the modified biochar treatments reduced the hydrolysis of urea and stimulated some nitrate-reduction-related bacteria crucial for NO3− retention. Hence, unlike the raw biochar and MgOPF treatments, MgOBF, SBF, and SPF hold promise in mitigating inorganic-N losses from fertilized soils while improving the soil's chemical properties.

Influence of Bamboo Biochar and Gibberellic Acid on Vegetative and Flower Production of Tagetes erecta L.

This research was carried out in open field Grdarasha, Agriculture College, Salahaddin University through March 18th to August 21th 2021 to study the effects of Bamboo biochar (0, 3, 6 and 9 ton.ha-1) as soil application and foliar spray GA3 (0, 200, 400 ml.l-1) on (Tagetes erecta L.) vegetative growth and flowering. The maximum number of leaves.plant-1, number of branches plant-1, vegetative growth dry mass (511.24, 61.82 and 115.63g) were observed from 9 ton.ha-1 of Bamboo biochar, and the highest stem diameter (22.31mm) was recorded from 6 ton.ha-1 of Bamboo biochar. However, the maximum values of number of leaves per plant (502.20), plant height (54.00 cm) and vegetative growth dry weight (109.09 g) were recorded in a higher GA3 concentration 400 ml.l-1. The interaction treatment of 6 ton.ha-1 of Bamboo biochar and 400 ml.l-1 GA3 gave the highest value of plant height and stem diameter (55.83 cm and 24.00 mm respectively). The best result time to reach %50 flowering (55.00 days) was obtained from 3 ton.ha-1 of Bamboo biochar, and the best results of time to reach 50% flowering (55.83 days), number of flowers per plant(46.02) and number of flowers per plot(184.08) were obtained from 400 ml.l-1 of GA3. The interaction treatment of 400 ml.l-1 of GA3 without Bamboo biochar gave the highest of number of flowers per plant (57.58), number of flowers per plot (230.33), flowers fresh weight per plant (212.17 g), flowers fresh weight per plot (848.67 g) and flowers fresh weight per hectar (7.07 ton).

Preparation of iron/calcium-modified biochar for phosphate removal from industrial wastewater

Phosphorous pollution is one of the main factors causing water eutrophication. For the treatment of wastewater, metal-modified biochar has emerged as a promising adsorbent with enhanced affinity for anions such as phosphate. Biochar modified with Fe or Ca are suitable for the treatment of low-concentration phosphorous wastewater (<100mg/L). However, the use of modified biochar to remove high concentrations of phosphate from industrial wastewater is challenging. In this study, biochar from poplar wood, wheat bran, bagasse, and bamboo were prepared and loaded with Fe and Ca, and its adsorption performance and degradation mechanism in the presence of high phosphate concentrations were investigated. The phosphate adsorption capacity of the Fe/Ca-modified biochar was 12–70 times higher than that before the modification. The best type of biochar for phosphate removal was iron/calcium oxide-modified bamboo biochar (ZFCO-BC) through batch experiments. X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES) analyses showed that ZFCO-BC reacted with wastewater to produce stable vivianite (Fe3(PO4)2·(H2O)8), which did not cause secondary release. ZFCO-BC exhibited a synergistic effect on the removal of 21 metals, including Cr, Cu, Co, Cd, As, Pb, and Y, from complex polluted water. Meanwhile, after 48 h of reaction, the concentration of phosphate decreased from 1660 to 0.061 mg/L, and the final value in the wastewater was lower than the phosphate discharge index indicated by the GB T31962-2015 Sewage Discharge into Urban sewer Water Quality Standard. This study shows that a single remediation system based on ZFCO-BC can remove phosphate and multiple heavy metals from contaminated water, providing a cost-effective treatment solution for complex polluted water bodies, such as industrial wastewater and groundwater.

Exploitation of indigenous bamboo macrophyte species and bamboo biochar for faecal sludge treatment with constructed wetland technology in the Sudano-Sahelian ecological zone

Treatment of faecal sludge (FS) has been a major challenge in most developing countries of Sub-Saharan Africa due to the difficulties in finding appropriate technology. Previous studies have however highlighted the potentials of the vertical flow constructed wetland for FS treatment, yet efforts in the identification of potential indigenous plant species as macrophyte for the Sudano-Sahelian ecological zone have been unsuccessful due to toxic levels of FS quality. This research studied the macrophyte potentials of indigenous bamboo species and bamboo biochar as a conditioner for FS treatment in a vertical flow constructed wetland (VFCW). Typical yard scale experiment consisting of filter media of sand supported at the base with gravels and planted with Bamboo shoots was used. Treatments were Bamboo Constructed Wetland (CW) and Faecal Sludge (FS) load only (CW-FS), Bamboo CW with a mixture of FS and Bamboo biochar (CW–BCH), unplanted drying bed with a mixture of FS and bamboo biochar (UDB-BCH) and an unplanted drying bed with FS (UDB-FS), and in triplicates. Control setup (CTR) consisted of Bamboo CW irrigated with wastewater. Morphological development (plant height, number of plants, number of leaves and culm diameter) of indigenous Bamboo species and reduction of faecal contaminants were monitored. Loading of FS was carried out in a single batch twice per week with a hydraulic loading rate of 56.47/mm/d with an annual Total Solid loading rate of 155.6 and 233.2 kg TS/m2/year for CW-FS and CW-BCH respectively. The bamboo species adapted to the complex wetland conditions, observed by a progressive increase in morphological development for all the treatments. Removal efficiencies of effluent quality parameters generally ranged from 70 to 99%, except for PO43−, TOC and TDS and indicator micro-organisms which were found below 50%. A strong positive linear relationship was determined among species growth parameter with coefficient (r) ranging between 0.83 – 0.99. Except for pH and TSS, all the effluent quality parameters exceeded the national allowable limits for safe discharge. Nonetheless, the study demonstrated positive potentials for adopting indigenous bamboo species as emergent macrophytes for FS treatment using VFCW. Further treatment to reduce contaminant levels in a second to a third series of a connected constructed is recommended wetland prior to reuse for agriculture.

Interaction investigation of three forest waste biochars and CaO in the process of Ca-L/CARBONOx

Ca-L/CARBONOx technology has realized the simultaneous removal of CO2 and NO in the flue gas from coal-fired power plants. Forest wastes are characterized by wide sources, low cost, high lignin content, and high chemical activity. In this study, three forest waste biochars including elm biochar (YB), fir biochar (SB) and bamboo biochar (ZB) were blended with CaO, and their simultaneous CO2/NO removal characteristics were compared. The interaction mechanism between CaO and biochar (BC) in the Ca-L/CARBONOx process was also discussed. Results show that the addition of biochar inhibits the pore structure collapse of CaO at higher cyclic numbers. CaO can also improves the NO removal efficiency for three biochars by catalyzing and providing active adsorption sites. The removal efficiency of NO by three biochars added with CaO are greater than 97% at 650 ℃ in the chemical control stage of CO2 adsorption. SB showed the best NO removal performance and reaction selectivity among the three biochars. Under the presence of CaO, CaO/YB and CaO/ZB have similar CO2 capture performance, while CaO/SB and CaO/ZB have the highest NO removal performance and the best NO reaction selectivity, respectively.

Role of tobacco and bamboo biochar on food waste digestate co-composting: Nitrogen conservation, greenhouse gas emissions, and compost quality

Anaerobic digestion is considered an environmentally benign process for the recycling of food waste into biogas. However, unscientific disposal of ammonium-rich food waste digestate (FWD), a by-product of anaerobic digestion induces environmental issues such as odor nuisances, water pollution, phytotoxicity and pathogen transformations in soil, etc. In the present study, FWD produced from anaerobic digestion of source-separated food waste from markets and industries was used for converting FWD into biofertilizer using 20-L bench scale composters. The issues of nitrogen loss, NH3 volatilization, and greenhouse gas N2O emission were addressed using in-situ composting technologies with the aid of tobacco and bamboo biochar produced at pyrolytic temperatures of 450 °C and 600 °C, respectively. The results demonstrated that the phytotoxic nature of FWD could be reduced into a nutrient-rich compost by mitigating nitrogen loss by 29–53% using 10% tobacco and 10% bamboo biochar in comparison with the control treatment. Tobacco biochar mitigates NH3 emission by 63% but enhances the N2O emission by 65%, whereas bamboo biochar mitigates both NH3 and N2O emissions by 48% and 31%, respectively. Overall, 10% tobacco and 10% bamboo biochar amendment could reduce total nitrogen loss by 29% and 53%, respectively. Furthermore, the biochar addition significantly enhanced the biodegradation rate of FWD and the mature compost could be produced within 21 days of FWD composting as seen by an increased seed germination index (>50% on dry weight basis). The results of this study could be beneficial in developing a circular bioeconomy locally with the waste-derived substrates.

The influence of biomass species and pyrolysis temperature on carbon-retention ability and heavy metal adsorption property during biochar aging

The variation of heavy metals (HMs) adsorption characteristics and carbon retention efficiency during aging are indispensable for evaluating the effectiveness of biochar during the remediation of HMs contaminated soil, but the effect of aging on retention efficiency in multiple systems and correlation relation between preparation process and biochar characteristics are still not clear. In this study, the influence and correlation characteristic of biomass species, pyrolysis temperature on the carbon-retention ability and HMs adsorption property in both single and binary systems of lead and copper during aging were investigated. The results illustrated that the content of oxygen-containing functional groups increased by 21.90% for bamboo biochar (BBC), 39.65% for rice husk biochar (RHC) and 16.99% for corncob biochar (CSC) after aging, as well as the ratio of O/C and (O + N/C), whereas the ratio of H/C and pH decreased. RHC500 exhibited the best anti-aging and carbon-retention ability due to the high pyrolysis temperature and SiC coating layer formed. Furthermore, the functional group complexation and π bond interaction increased after aging, whereas the inorganic precipitation and ion exchange decreased, increasing the competitive adsorption capacity of Cu and decreasing the adsorption stability of HMs.

Direct air capture of CO2 by KOH-activated bamboo biochar

Direct air capture (DAC) of CO2 is considered one of the most promising carbon capture methods to reduce ambient CO2 concentration for climate change mitigation. Biochar represents an attractive adsorbent for DAC because it is environmentally friendly and cost-effective. In this work, KOH-activated bamboo biochar shows the CO2 capture capacity of 3.49 mmol g−1 (25 °C, 1 bar), and it is used as an adsorbent to perform direct air capture using a fixed-bed reactor with an ambient CO2 capture capacity of up to 51.74 μmol g−1. Furthermore, the effect of relative humidity on CO2 adsorption by biochar was investigated and exhibited promising stability under 2.7% relative humidity. However, the biochar activity for CO2 capture is reduced to 63.88% under 67.1% humidity after 50 cycles.

Biochar improves compost humification, maturity and mitigates nitrogen loss during the vermicomposting of cattle manure-maize straw

Maintaining humidification and inhibiting nitrogen losses during vermicomposting process have emerged to be key factors for high-quality productions. Previous data have showed outstanding functions of biochar addition in improving vermicomposting quality. In this study, the influence of bamboo biochar (BB) and rice husk biochar (RHB) addition on compost maturity, humification and nitrogen loss was evaluated in the vermicomposting of cattle manure and maize straw. Results revealed that BB or RHB amendment improved organic matter decomposition, enhanced humification and maturity of compost, particularly in the 10% BB treatment, which exerted the highest humic acids content and GI value. Furthermore, BB or RHB addition significantly reduced nitrogen losses, in which the volatilization of NH3 and N2O were reduced by 24.93%–66.23% and 14.91%–55.12%. The fewest nitrogen loss was detected in the treatment of 10% BB. Biochar inhibited nirK, nirS but promoted AOB-amoA, nosZ expression; fewer N2O producing bacteria (Pseudomonas, Devosia, Luteimonas genus) were observed in the biochar treatment, and thereby decreased the N2O emission. Therefore, 10% BB addition for co-vermicomposting cattle manure and maize straw is an efficient way to increase humification, maturity, and reduce nitrogen loss, and future applications following this strategy is believed to generate better productions.

Removal of reactive violet 5 azodye (V5R) using bamboo, and calabash biochar

We assess the adsorption capacity of bamboo and calabash biochar (BB and CB). Using 10–50 mg/L Reactive Violet 5 Azo dye (V5R) adsorbate, the kinetics, and adsorption isotherms are investigated. We pyrolyzed the bamboo, and calabash biomass at 500 °C, washed, and oven dried at 120 °C for 48 h. The Brunauer–Emmett–Teller (BET) method indicates that the BB and CB average pore diameters are 21.1 nm and 26.5 nm, with specific surface areas of 174.67 m2/g and 44.78 m2/g, respectively. The SEM reveals a larger granular shape of the CB having pinholes on the surface, but the BB exhibited interconnected structures like a mesh. The FTIR shows C=C, C=O, O–H, and C–O–C as the predominant functional groups on both BB and CB. The adsorption of V5R on BB and CB follows pseudo-second-order kinetics and favors Langmuir isotherm with maximum adsorption capacities of 5.106 mg/g, and 0.010 mg/g, respectively. The BB adsorbs 70.9–96% V5R, whilst CB adsorbs 0.1–0.2 % only. The results suggest that bamboo biochar has the potential to eliminate 70.9–96% of 10–50 mg/L V5R from an aqueous solution, hence suitable for removing V5R. In this study, we have also presented a prototype expected to eliminate 91.6%–99.8% of the V5R from an aqueous solution.

Bamboo Biochar and Zinc Oxide Nanoparticles Improved the Growth of Maize (Zea mays L.) and Decreased Cadmium Uptake in Cd-Contaminated Soil

Cadmium (Cd) has attained top priority among all the toxic trace elements, and it easily accumulates in the human body through various pathways. The current pot study was focused on the impacts of foliar spray zinc oxide nanoparticles (ZnO NPs) (0, 50, 75, 100 mg·L−1), alone or combined with soil-applied bamboo biochar (1.0% w/w), on the maize growth and Cd and Zn accumulations in the grains of maize under Cd-contaminated soil. The results showed that the maize-growth, photosynthesis, and gas-exchange attributes were accelerated by the foliar-applied ZnO NPs, and this effect was further enhanced by the bamboo biochar application in combination with ZnO NPs. All the amendments decreased the electrolyte leakage (EL) and malondialdehyde (MDA) and hydrogen peroxide (H2O2) contents, and they enhanced the activities of the antioxidant enzymes in the leaves and roots of the maize more than the control. The Cd concentrations in the shoots decreased by 74.55%, in the roots 66.38%, and in the grains by 76.19% after the bamboo biochar combined with a foliar spray of 100 mg·L−1 ZnO NPs. The current study concluded that the combination of the foliar spray of ZnO NPs and soil-applied bamboo biochar is a feasible strategy for safely growing crops on Cd-contaminated soils.

Mechanical, fracture toughness, and Dynamic Mechanical properties of twill weaved bamboo fiber‐reinforced Artocarpus heterophyllus seed husk biochar epoxy composite

AbstractThis research aimed to find the effect of Artocarpus heterophyllus fruit seed husk biochar (ASB) and twill weaved bamboo fiber (TBF) in mechanical, DMA, and fracture toughness behavior of epoxy‐based composite. The surface of both weaved bamboo fiber and biochar was treated with amino silane before composite making. In this investigation, the laminates were fabricated by hand layup process and analyzed by appropriate ASTM standards. Results of this study revealed that the incorporation of 40 vol.% twill weaved bamboo fiber (EB) into the resin improved the mechanical properties. The load distribution was uniform with twilled weaving. For composite designation EBJ3, the maximum measured tensile strength was 168 MPa, the tensile modulus is 6.24 GPa, the flexural strength is 195 MPa, and the flexural modulus is 6.85 GPa, the izod impact is 6.24 J, and the hardness is 90 shore‐D. Similarly, the maximum storage modulus and lowest loss factor for the composite designation EBJ3 were measured to be 3.8 GPa and 0.4, respectively. Moreover, the maximum measured fracture toughness and energy release rate is 39.4 MPa.√m and 0.88 MJ/m2 for composite designation EBJ3 with 5.0% biochar and 40% bamboo fibers in volume. The SEM fractography revealed that the matrix molecules are adhered to the fiber, indicating enhanced bonding. These biomass waste converted fruit seed husk biochar and industrial crop bamboo fiber epoxy composites could be used as workable material in structural, defense, automotive, and domestic product‐making applications.

Bamboo Chopstick Biochar Electrodes and Enhanced Nitrate Removal from Groundwater

The nitrate pollution of groundwater can cause serious harm to human health. Biochar electrodes, combined with adsorption and electroreduction, have great potential in nitrate removal from groundwater. In this study, bamboo chopsticks were used as feedstocks for biochar preparation. The bamboo chopstick biochar (BCBC), prepared by pyrolysis at 600 °C for 2 h, had a specific surface area of 179.2 m2/g and an electrical conductivity of 8869.2 μS/cm, which was an ideal biochar electrode material. The maximum nitrate adsorption capacity of BCBC-600-2 reached 16.39 mg/g. With an applied voltage of 4 V and hydraulic retention time of 4 h, the nitrate removal efficiency (NRE) reached 75.8%. In comparison, the NRE was only 32.9% without voltage and 25.7% with graphite cathode. Meanwhile, the average nitrate removal rate of biochar electrode was also higher than that of graphite cathode under the same conditions. Therefore, biochar electrode can provide full play to the coupling effect of adsorption and electroreduction processes and obtain more powerful nitrate removal ability. Moreover, the biochar electrode could inhibit the accumulation of nitrite and improve the selectivity of electrochemical reduction. This study not only provides a high-quality biochar electrode material, but also provides a new idea for nitrate removal in groundwater.

Development of natural rubber-bamboo biochar composites for vibration and noise control applications

The present study focuses on the utilization of bamboo biochar (BB) as a filler in natural rubber (NR) composites. This work is the first attempt to investigate the influence of BB loading on the vibration damping and acoustical properties of NR composites. NR-BB composites were prepared according to the ASTM D3182-21a standard. Vibration damping and acoustical properties were examined using the Obrest beam (ASTM E756-05) and four microphone impedance tube (ASTM E2611-19) methods. Noteworthy, the vibration damping ratio or system loss factor (ξ) obtained maximum for the fourth mode of vibration (NR- ξ = 33.19, NR/10BB- ξ = 17.46, and NR/20BB- ξ = 13.50) in the free layer damping (FLD) configurations. However, the sound transmission loss (STL) was enhanced by 8% and 11% compared to NR composites upon adding 10 and 20 phr of BB, respectively. In addition to vibration damping and STL, the loading of BB in the NR matrix positively influenced physical, mechanical, and thermal properties.