Biochar alleviates apple replant disease by reducing the growth of Fusarium oxysporum and regulating microbial communities

Apple replant disease(ARD)negatively affects plant growth and reduces yields in replanted orchards.In this study,biochar was applied to apple replant soil with Fusarium oxysporum.Our aim was to investigate whether biochar could promote plant growth and alleviate apple replant disease by reducing the growth of harmful soil microorganisms,changing soil microbial community structure and improving the soil environment.This experiment included five treatments:apple replant soil(CK),methyl bromide fumigation apple replant soil(FM),replant soil with biochar addition(2%),replant soil with F.oxysporum spore solution(8×10^(7)spores·mL^(-1)),and replant soil with biochar and F.oxysporum spore solution addition.Seedling biomass,the activity of antioxidant enzymes in the leaves and roots,and soil environmental variables were measured.Microbial community composition and community structure were analyzed using 16SrDNA and ITS2 gene sequencing.Biochar significantly reduced the abundance of F.oxysporum and increased soil microbial diversity and richness.Biochar also increased the soil enzyme activities(urease,invertase,neutral phosphatase,and catalase),the biomass(plant height,fresh weight,dry weight)and the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase).The root indexes of apple seedlings was also increased in replant soil by biochar.In sum,biochar promoted the growth of plants,improved the replant soil environment,and alleviated apple replant disease.

Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous structure.The adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic performance.Moreover,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical calculation.Considering the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

Feasibility Evaluation of Using Biochar-based Permeable Reactive Barrier for the Remediation of Mercury and Arsenic Composite Polluted Water Bodies

This study employed a modified biochar material to construct a permeable reactive barrier(PRB)for the treatment of water bodies polluted with mercury and arsenic.The experimental results demonstrated that the addition of goethite-modified biochar significantly enhanced the remediation efficiency of As(III),achieving a maximum removal rate of 100%.Conversely,pure biochar exhibited high efficiency in the removal of Hg(II),with a maximum removal rate approaching 100%.Furthermore,the pH level of the water significantly influenced the adsorption efficiency of heavy metal ions,with the optimal removal performance observed at a pH of 6.0.The PRB system demonstrated excellent removal rates under low concentrations of heavy metals.However,as the concentration increased,the remediation efficiency exhibited a slight decrease.In summary,the findings of this study provide compelling evidence for the use of modified biochar in the construction of PRBs for the remediation of mercury and arsenic-polluted water bodies.Furthermore,the study reveals the mechanism by which pH and heavy metal concentration influence remediation efficiency.

Exploring the combination of biochar‐amended soil and automated irrigation technology for water regulation and preservation in green infrastructure

Biochar is a carbon sink material with the potential to improve water retention in various soils.However,for the long‐term maintenance of green infrastructure,there is an additional need to regulate the water contents in the covers to maintain vegetation growth in semiarid conditions.In this study,biochar‐amended soil was combined with subsurface drip irrigation,and the water preservation characteristics of this treatment were investigated through a series of one‐dimensional soil column tests.To ascertain the best treatment method specific to semiarid climatic conditions,the test soil was amended with 0%,1%,3%,and 5%biochar.Automatic irrigation devices equipped with soil moisture sensors were used to control the subsurface water content with the aim of enhancing vegetation growth.Each soil column test lasted 150 h,during which the volumetric water contents and soil suction data were recorded.The experimental results reveal that the soil specimen amended with 3%biochar is the most water‐saving regardless of the time cost.Soil with a higher biochar content(e.g.,5%)consumes a more significant amount of water due to the enhancement of the water‐holding capacity.Based on the experimental results,it can be concluded that the appropriate ratio can be determined within 1%–3%,which can reduce not only the amount of irrigated/used water but also the time cost.Such technology can be explored for water content regulation in green infrastructure and the development of barriers for protecting the environment around deep underground waste containment.

Dredged marine soil stabilization using magnesia cement augmented with biochar/slag

Dredged marine soils(DMS)have poor engineering properties,which limit their usage in construction projects.This research examines the application of reactive magnesia(rMgO)containing supplementary cementitious materials(SCMs)to stabilize DMS under ambient and carbon dioxide(CO_(2))curing conditions.Several proprietary experimental tests were conducted to investigate the stabilized DMS.Furthermore,the carbonation-induced mineralogical,thermal,and microstructural properties change of the samples were explored.The findings show that the compressive strength of the stabilized DMS fulfilled the 7-d requirement(0.7-2.1 MPa)for pavement and building foundations.Replacing rMgO with SCMs such as biochar or ground granulated blast-furnace slag(GGBS)altered the engineering properties and particle packing of the stabilized soils,thus influencing their performances.Biochar increased the porosity of the samples,facilitating higher CO_(2) uptake and improved ductility,while GGBS decreased porosity and increased the dry density of the samples,resulting in higher strength.The addition of SCMs also enhanced the water retention capacity and modified the pH of the samples.Microstructural analysis revealed that the hydrated magnesium carbonates precipitated in the carbonated samples provided better cementation effects than brucite formed during rMgO hydration.Moreover,incorporating SCMs reduced the overall global warming potential and energy demand of the rMgO-based systems.The biochar mixes demonstrated lower toxicity and energy consumption.Ultimately,the rMgO and biochar blend can serve as an environmentally friendly additive for soft soil stabilization and permanent fixation of significant amounts of CO_(2) in soils through mineral carbonation,potentially reducing environmental pollution while meeting urbanization needs.

Key Physical Factors Affecting Spatial-temporal Variation of Labile Organic Carbon Fractions by Biochar Driven in Mollisols Region of Northeast China

Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between physical properties and LOC fractions. A field positioning experiment was performed in Mollisols region of Northeast China to evaluate the influence of maize stalk biochar on the spatial distribution and temporal changes of physical properties and LOC fractions. Maize stalk biochar treatments included C1(1.5 kg·hm^(-2)), C2(3 kg·hm^(-2)), C3(15 kg·hm^(-2)), C4(30 kg·hm^(-2)), and CK(0). The results showed that maize stalk biochar increased soil water contents(SWC) and soil porosity(SP), but reduced bulk density(BD). Maize stalk biochar reduced dissolved organic carbon(DOC) contents in the 0-20 cm soil layer, ranging from 0.25 g·kg^(-1) to 0.31 g·kg^(-1) in harvest period, while increased in the 20-40 cm soil layer. In addition, the application of biochar had a significant impact on the spatial distribution and temporal change of SWC, BD, SP, DOC, hot-water extractable carbon(HWC), acid hydrolyzed organic carbon(AHC Ⅰ, Ⅱ), and readily oxidized organic carbon(ROC). High amounts of maize stalk biochar up-regulated the contents of soil organic carbon SOC, HWC, AHC Ⅰ, AHC Ⅱ, and ROC. In addition, SWC and SP were the key physical factors to affect LOC fractions. In conclusions, maize stalk biochar could improve physical properties, and then influence LOC fractions, and maize stalk biochar could be used as an organic amendment for restoring degraded soils governed by their rates of addition.

Interaction between Biochar and Algae on Problem Soil

An in-vitro experiment was conducted to assess the interaction between biochar and algae on a problem soil. Experiments were performed with and without algae to observe the effectiveness of algae for overcoming the challenges posed by problem soils. At the end of incubation periods, the adsorption and desorption of phosphorus (P) on a problem soil vis-á-vis algal inoculation were determined. Our results showed that different types of biochars adsorbed different amounts of P suggesting that the source of biochar played a crucial role in determining its behavior towards P. Tannery waste biochar significantly adsorbed 147% and 35% more P compared to that of the chicken litter and orange peel biochars respectively. Significant reductions in adsorption were observed when the biochar was used in combination with the algae which could be due to the beneficial effects of algae leading to the amelioration of the problem soil. Adsorption was reduced to 34%, 24% and 20% for the orange peel biochar + algae, chicken litter biochar + algae and tannery waste biochar + algae, respectively compared to the corresponding biochars present as a single solid. Phosphorus (P) desorption was also reduced significantly in presence of algal inoculation. Overall our findings suggest that the application of algae along with biochar in the problem soil could reduce the adsorption of P which would influence the availability of P.

Synthesis and Characterization of β-Cyclodextrin Modified Biochar Environmental Remediation Materials

In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cyclodextrin (β-CD) was used to modify biochar (BC). The prepared modified biochar materials were labeled with β-CDBC, β-CDBC-Na, β-CDBC-CA and β-CDBC-H, respectively. The infrared spectrum, X-ray diffractometer, scanning electron microscope and specific surface area of the four modified materials were tested. The results showed that the C-O stretching vibration peak at 1020 cm−1 of the modified materials was slightly offset compared with that of biochar. The characteristic absorption peaks of XRD pattern decrease obviously at 2θ = 26.7˚ and 29.5˚. It can be obviously observed on the electron microscope image that the surface is loaded or formed clathrates, and BET data and graphs also show that the specific surface area of the modified biochar is larger. Therefore, β-cyclodextrin successfully modified biochar and formed clathrates on the surface of biochar or was loaded in the pore structure of biochar, especially β-CDBC-CA achieved better modification effect. Because biochar and β-cyclodextrin raw materials are cheap, easy to prepare and green, and less prone to secondary pollution, it has a good advantage in environmental governance.

Adsorption Effect of Phosphate Modified Grape Branch Biochar on Cd2

Two major problems facing agriculture at present are soil pollution and the disposal of solid wastes generated during plant growth. The method of preparing biochar from solid wastes produced by plants is a means of maximizing the use of resources to combat the problem of soil pollution. In this study, we did not choose straw in the traditional sense but the waste branches from grape pruning, which has higher lignin cellulose, as the raw material. The biochar derived from grape branches pyrolyzed at 300˚C for two hours was utilized as a raw material to prepare modified biochar with varying concentrations of phosphoric acid. The adsorption performance and mechanism of Cd2 were explored through experiments involving different concentrations, addition amounts, reaction times, kinetic analyses, and isothermal adsorption tests. The findings indicated that the optimal adsorption of Cd2 occurred with a 20% phosphoric acid concentration, achieving the highest adsorption rate of 84.62%. At a dosage of 10 g/L, the maximum adsorption capacity reached 7.02 mg/g. The adsorption kinetics and isothermal adsorption of Cd2 on biochar modified with 0.2% phosphoric acid (0.2 PB) closely followed the pseudo-first-order kinetics model (R2 > 0.98) and the Freundlich model (R2 > 0.97), respectively. This suggests that the adsorption process involves both physical and chemical mechanisms. SEM and FTIR analyses revealed that phosphoric acid modification primarily increased the biochar’s specific surface area and enhanced certain original functional groups. The adsorption process predominantly involved rapid ion diffusion and chemical adsorption, as confirmed by kinetic analysis and isothermal adsorption model analysis. In summary, the adsorption efficiency of 0.2 PB significantly improved, showing potential and feasibility for heavy metal remediation in soil. This supports the environmentally friendly concept of “treating waste with waste”.

响应面法优化制备La-Biochar复合材料及其对As(Ⅲ)的吸附研究

为优化La-Biochar复合材料(La-B)制备工艺,以玉米秸秆和氯化镧为原料,As(Ⅲ)吸附量和去除率为响应指标,采用Box-Behnken Design(BBD)响应面法研究制备条件,系统考察吸附剂投加量和pH对吸附效果影响,并探究其吸附动力学和吸附热力学特性。结果表明:(1)La-B最佳制备条件为炭化时间120 min,物料比30%,炭化温度750℃,NaOH添加量0.5 g;(2)pH=10,吸附剂用量0.1 g时,La-B对20 mg/L的As(Ⅲ)溶液吸附效果最佳,此时As(Ⅲ)去除率达99.01%;(3)As(Ⅲ)等温吸附过程可用Freundlich模型描述,吸附过程遵循准二级扩散动力学模型;(4)La-B对As(Ⅲ)的吸附在高温条件下为自发的吸热反应过程。

Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals

Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of pollutants.In this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants.

Effects of biochar-amended alkali-activated slag on the stabilization of coral sand in coastal areas

Coral sand is widely encountered in coastal areas of tropical and subtropical regions.Compared with silica sand,it usually exhibits weaker performance from the perspective of engineering geology.To improve the geomechanical performance of coral sand and meet the requirement of foundation construction in coastal areas,a novel alkali activation-based sustainable binder was developed.The alkaliactivated slag(AAS)binder material was composed of ground granulated blast-furnace slag(GGBS)and hydrated lime with the amendment of biochar,an agricultural waste-derived material.The biocharamended AAS stabilized coral sand was subjected to a series of laboratory tests to determine its mechanical,physicochemical,and microstructural characteristics.Results show that adding a moderate amount of biochar in AAS could improve soil strength,elastic modulus,and water holding capacity by up to 20%,70%,and 30%,respectively.Moreover,the addition of biochar in AAS had a marginal effect on the sulfate resistance of the stabilized sand,especially at high biochar content.However,the resistance of the AAS stabilized sand to wet-dry cycles slightly deteriorated with the addition of biochar.Based on these observations,a conceptual model showing biochar-AAS-sand interactions was proposed,in which biochar served as an internal curing agent,micro-reinforcer,and mechanically weak point.

Biochar’s Electrochemical Properties Impact on Methanogenesis: Ruminal vs. Soil Processes

The chemical composition of biochar and the pyrolysis temperature, under which biochar was produced, determine its electrochemical properties. Electrical conductivity, pseudo-capacitance, and double layer capacitance are the three main electrochemical properties of biochar. Due to the electrical conductivity biochar is able to interfere with the electrons flow and play a dual role of an electron donor or an electron acceptor. The average conductivity of biochar is 229.20 S/m. Pseudocapacitance of biochar lets it serve as a hydrogen sink, taking up the hydrogen produced by protozoa and preventing it from participating in methane-producing reactions in the rumen environment. The average value of biochar’s pseudocapacitance is 228 F·g-1. Positive and negative charges get stored due to the absorption of ions onto the carbon surface, which happens because of the existence of double layer capacitance as one of biochar’s electrochemical properties. Biochar’s double layer capacitance values can reach the point of 110.8 F·g-1. The electrochemical properties of biochar are directly co-dependent with its redox potential and pH. Electrical conductivity, pseudocapacitance, and double layer capacitance can significantly influence biochemical processes in the rumen and, thus, need to be studied practically.

Naturally Nitrogen-Doped Biochar Made from End-of-Life Wood Panels for SO_(2) Gas Depollution

Reconstituted wood panels have several advantages in terms of ease of manufacturing,but their shorter life span results in a huge amount of reconstituted wood panels being discarded in sorting centers yearly.Currently,the most common approach for dealing with this waste is incineration.In this study,reconstituted wood panels were converted into activated biochar through a two-step thermochemical process:(i)biochar production using pilot scale fast pyrolysis at 250 kg/h and 450℃;and(ii)a physical activation at three temperatures(750℃,850℃ and 950℃)using an in-house activation furnace(1 kg/h).Results showed that the first stage removed about 66% of the nitrogen from the wood panels in the form of NO,NH3,and trimethylamine,which were detected in small amounts compared to emitted CO_(2).Compared to other types of thermochemical conversion methods(e.g.,slow pyrolysis),isocyanic acid and hydrogen cyanide were not detected in this study.The second stage produced activated biochar with a specific surface area of up to 865 m^(2)/g at 950℃.The volatile gases generated during activation were predominantly composed of toluene and benzene.This two-step process resulted in nitrogen-rich carbon in the form of pyrrolic and pyridinic nitrogen.Activated biochars were then evaluated for their SO_(2) retention performance and showed an excellent adsorption capacity of up to 2140 mg/g compared to 65 mg/g for a commercial activated carbon(889 m^(2)/g).End-of-life reconstituted wood panels and SO_(2) gas are problematic issues in Canada where the economy largely revolves around forestry and mining industries.

Improving the electrocatalytic activity of Fe,N co-doped biochar for polysulfide by regulation of N-C and Fe-N-C electronic configurations

The conversion of agricultural residual biomass into biochar as a sulfur host material for Li-S batteries is a promising approach to alleviate the greenhouse effect and realize waste resource reutilization.However,the large-scale application of pristine biochar is hindered by its low electrical conductivity and limited electrocatalytic sites.This paper addressed these challenges via the construction of Fe-N co-doped biochar(Fe-NOPC)through the copyrolysis of sesame seeds shell and ferric sodium ethylenediaminetetraacetic acid(NaFeEDTA).During the synthesis process,NaFeEDTA was used as an extra carbon resource to regulate the chemical environment of N doping,which resulted in the production of high contents of graphitic,pyridinic,and pyrrolic N and Fe-Nx bonds.When the resulting Fe-NOPC was used as a sulfur host,the pyridinic and pyrrolic N would adjust the surface electron structure of biochar to accelerate the electron/ion transport,and the electropositive graphitic N could be combined with sulfur-related species via electrostatic attraction.Fe-Nx could also promote the redox reaction of lithium polysulfides due to the strong Li-N and S-Fe bonds.Benefiting from these advantages,the resultant Fe-NOPC/S cathode with a sulfur loading of 3.8 mg·cm^(-2)delivered an areal capacity of 4.45 mAh·cm^(-2)at 0.1C and retained a capacity of 3.45 mAh·cm^(-2)at 1C.Thus,this cathode material holds enormous potential for achieving energy-dense Li-S batteries.

Chemical Oxidation Effects on Anion Exchange and Nitrate Sorption Capacity of Biochar for Ruminal Methanogenesis Inhibition

The chemical composition of biochar is determined by the chemical profile of the material the by-product is made of and the pyrolysis conditions. Analysis of commercial biochar detected similarities to the chemical profile of hardwood, which was used as an object of pyrolysis for biochar production and showed the presence of bridge-forming cations, such as manganese, iron, and sodium. Despite frequently being reported in existing literature, the current study showed that the redox potential of biochar is not associated with biochar’s ability to recover certain anions. No association was detected between biochar’s redox potential and the material nitrate sorption capacity. In fact, higher redox potential values were associated with lower nitrate absorption. In the case of the anion exchange capacity of biochar, a direct association between this electrochemical property of the by-product and its redox potential was observed. However, redox potential’s impact on anion exchange capacity can be inhibited by the presence of organic compounds in biochar’s chemical profile. The chemical oxidation of biochar is a complex process and is a research priority for a potential role to mitigate enteric methanogenesis in livestock.

Response of soil bacterial community to biochar application in a boreal pine forest

Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina NovaSeq sequencing combined with functional annotation of prokaryotic taxa(FAPROTAX)analysis was used to investigate the eff ect of biochar pyrolysis temperatures,the amount of applied biochar,and the period since the biochar application(2-and 3-year)on soil bacterial communities.The results show that biochar pyrolysis temperatures(500℃ and 650℃)and the amount of applied biochar(0.5 kg m^(−2)and 1.0 kg m^(−2))did not change soil properties.Nevertheless,the interaction of biochar pyrolysis temperature and the amount had signifi cant eff ects on bacterial species richness and evenness(P<0.05).The application of biochar produced at 500℃ had a lower abundance of Actinobacteria and Verrucomicrobia,while that produced at 650℃ had a higher abundance of Conexibacter and Phenylobacterium.When biochar produced at 650℃ was applied,applying 0.5 kg m^(−2)had a higher abundance of Cyanobacteria,Conexibacter,and Phenylobacterium than that of 1.0 kg m^(−2)(P<0.05).Functionally,the abundance of the aromatic compound degradation group increased with the extension of application time and increase of pyrolysis temperature.The time since application played an important role in the formation of soil bacterial communities and their functional structure.Long-term studies are necessary to understand the consequence of biochar on bacterial communities in boreal forests.

Synthesis of Modified Walnut Shell Biochar and Its Performance of Cadmium Adsorption

Biochar is a functional and environmentally friendly material mainly made from by-products of industrial and agricultural production as raw material, which is cracked at high temperatures and slow speeds. The preparation of biochar requires the thermochemical conversion of biomass in an oxygen-restricted environment. Different raw materials and preparation processes result in biochar with different internal structures and biofunctional groups, which often have different properties. Adsorption of heavy metal pollutants is one of the main research directions for biochar application, and there are still areas that can be improved in the current research for biochar for treating heavy metal wastewater. In this study, we take the treatment of cadmium-containing wastewater as an example, walnut shell biochar (WSBC) as a carrier, iron(VI) compounds as a modifying reagent, and test the performance of cadmium-containing wastewater treatment using simulated cadmium-containing wastewater by adjusting the pyrolysis process and modification method at the same time to find the optimal experimental scheme, and give a reasonable theoretical explanation in relation to the results of the characterization tests, such as SEM, FT-IR, and so on. The characterized results show that iron(VI) compound (K2FeO4)-modified WSBC has a significant ability to remove cadmium contamination in the wastewater (remove 96.62% of cadmium in 1 minute), and its structure is different from other iron compound-modified ones. The aim of this study is to improve the efficiency of cadmium adsorption by specific types of biochar, while realizing the whole process as environmentally friendly as possible.

Optimization and Thermodynamic Studies of Lead (II) and Cadmium (II) Ions Removal from Water Using Musa acuminate Pseudo-Stem Biochar

We recently found out that water from the Ugandan stretch of the Kagera transboundary river (East Africa) is contaminated with lead (Pb2+) and cadmium (Cd2+) ions at levels that are above permissible limits in drinking water. Because lignocellulosic biomass-based adsorbents have been explored for the remediation of metal ions from water, this study investigated the potential of Musa acuminata pseudo-stem (MAPS) biochar for the remediation of Pb2+ and Cd2+ ions from water. Batch adsorption experiments were performed to optimize the adsorption conditions while the isotherms were analyzed using Freundlich and Langmuir models. Results showed that the maximum adsorption capacity at equilibrium was 769.23 mg/g and 588.23 mg/g for Pb2+ and Cd2+ ions, respectively. Langmuir isotherm model provided the best fit for the data, and it was favorable since all r2 values (Cd2+ = 0.9726 and Pb2+ = 0.9592) were close to unity. Gibb’s free energy change was found to be negative for both metals, implying the feasibility of the adsorption process. Correspondingly, the enthalpy change was positive for both metal ions which revealed that the adsorption process was endothermic and it occurred randomly at the solid-liquid interface. These results suggested that biochar from MAPs could be utilized for the removal of Pb2+ and Cd2+ from polluted water in the Kagera transboundary river to make it suitable for domestic use. Further studies should consider chemical modification of the biochar as well as characterization to examine the chemical nature of the biochar.

In-situ grown Ni Co bimetal anchored on porous straw-derived biochar composites with boosted microwave absorption properties

With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,composites consisting of straw-derived biochar combined with NiCo alloy were successfully fabricated through high-temperature carbonization and subsequent hydrothermal reaction.The electromagnetic parameters of the porous biocarbon/NiCo composites can be effectively modified by altering their NiCo content,and their improved absorbing performance can be attributed to the synergy effect of magnetic-dielectric characteristics.An exceptional reflection loss of-27.0 dB at 2.2 mm thickness and an effective absorption bandwidth of 4.4 GHz(11.7-16.1 GHz)were achieved.These results revealed that the porous biocarbon/NiCo composites could be used as a new generation absorbing material because of their low density,light weight,excellent conductivity,and strong absorption.