Showing 14 results for Biochar
M. Zolfi Bavariani, A. Ronaghi, N. Karimian, R. Ghasemi, J. Yasrebi,
Volume 20, Issue 75 (5-2016)
Abstract
This study was conducted to investigate the effects of poultry manure (PM) and its derived biochars on chemical properties of a sample calcareous soil. Poultry manure and its derived biochars at 200(B200), 300(B300) and 400(B400)°C were incorporated with 400 g of soil at 2% level (w/w) and incubated for 150 days. Some chemical properties of soil and bio-availability of some nutritional ingredients such as phosphorous, potassium, iron, manganese, zinc and copper were determined at different times of incubation. Soil nutrients availability, organic carbon (OC), electrical conductivity (EC) and cation exchange capacity (CEC) increased by addition of all these organic substances. Biochars prepared at higher temperatures were more effective in increasing soil OC and its durability. Addition of PM and B200 decreased soil pH, whereas B400 increased it. Although highest soil EC was observed in B300 and B400 treated samples in the early stages of incubation, the rate of increasing in soil EC was higher at PM and B200 treated samples. In general, it was concluded that biochar prepared at 300°C had the highest effect on availability of nutrients and their durability in the soil.
M Zolfi Bavariani, A. Ronaghi, N. Karimian, J. Yasrebi, Reza Ghasemi,
Volume 21, Issue 1 (6-2017)
Abstract
This study was conducted to investigate the effects of poultry manure (PM) and derived biochars on phosphorous (P) availability and apparent recovery in a calcareous soil. Treatments consisted of four rates of P (0, 30, 60 and 90 µgg-1) and five organic substances (blank, poultry manure and derived biochars at 200, 300 and 400°C). organic substances were incorporated with 400 g of soil at 2% level (w/w). All soil treated samples plus control were incubated for 150 days. Soil P availbility determined at 8 different stage of incubation time period. Phosphorous availability was less in untreated soil samples with organic substances and also decreased with time. Although P recovery from inorganic P fertilizer was high in the early stages of incubation time compared to treated soil samples but decreased with time, if not treated with organic substances. Phosphorus availability and recovery increased with time in PM and biochares treated soil samples. Simultanous application of inorganic P and organic substances decreased apparent P recovery. Negative interaction obsorved between organic substances and high rates of inorganic P fertilizer on P availability. It was concluded that PM biochar prepared at 300°C had the highest effect on adjusting P availability in calcareous soil.
T. Rahimi, A. Moezzi, S. Hojati,
Volume 22, Issue 1 (6-2018)
Abstract
Biochar is a soil amendment that has a high capacity to adsorb heavy metals. The aim of this study was to identify the influence of cow manure and its biochar on nickel adsorption and to determine the best models to describe the kinetics of Ni retention. Accordingly, cow manure and its biochar were added to the soils at the levels of 0, 2 and 4%, and samples were incubated for 90 days. Soil samples were equilibrated with 100 mg L-1 Ni solutions for periods of 1 to 2880 min. Then, the concentration of nickel was measured. The Ni adsorption data were fitted to seven commonly used kinetic models. The results showed that cow manure and its biochar application in all times and levels increased nickel adsorption more than the control. There was also a significant difference (P<0.05) between cow manure and its biochar. Application of 4% biochar, as compared with the same level of cow manure, and the control, increased the Ni adsorption by 23 and 44%, respectively. Power function was the best fitted model describing the patterns of Ni adsorption, as evidenced by the relatively high values of R2 and the low values of SE. However, the Elovich function had some R2 similar to that of power function, but it could not be used as an adequate function to investigate the kinetics of nickel adsorption due to their high values of SE. The zero order, the first order, the second order, the third order, and parabolic diffusion equations were not well fitted to the Ni adsorption data.
R. Torki Harchegani, N. Mirghaffari, M. Soleimani Aminabadi,
Volume 23, Issue 2 (9-2019)
Abstract
Fruits and citrus wastes are generated in the food industry in large quantities. Their management in Iran, as one of the major hubs of fruits and citrus production, is of great importance. In this study, the biochar samples were prepared from pomegranate, orange and lemon peel waste produced in a juice factory using the pyrolysis process in the range of 400-500 °C; then their efficiency for zinc adsorption from an aqueous solution was investigated. The kinetic and isotherm data of zinc adsorption were fitted by the linear and nonlinear forms of the Langmuir and Frendlich isotherm models and the first-order and second-order pseudo-kinetics models. The results showed that under the experimental conditions applied, the maximum amount of zinc absorption by biochars derived from pomegranate, orange and lemon peel was 2.42, 1.83 and 3.17 mg/g, respectively. The results of adsorption isotherm models also showed that the use of the linear form could lead to a completely different interpretation, as compared to the original form of the model. Based on the linear forms, the Langmuir isotherm was the best; meanwhile, according to the non-linear forms, the Freundlich isotherm was the best model to describe the adsorption data. In addition, the reaction kinetics indicated that both original and linear models had the same results, and the data were better fitted by the pseudo-second order model.
A. Ebrahimi, M. Shayannejad, M. Reza Mosaddeghi,
Volume 23, Issue 4 (2-2020)
Abstract
Wetting pattern in a trickle irrigation system is one of the most important characteristics that should be taken into consideration for designing the irrigation systems. Improving the dimensions of the wetting pattern will increase the water use efficiency and irrigation systems. The objective of this study was to investigate the effect of rice husk and its biochar application on the wetting pattern in a silty clay soil under surface trickle irrigation. A box with the length of 200, the width of 50 and the height of 100 cm was used. To easily fill and empty the model, it was filled up to a height of 50 cm. The rice husk and its biochar were added to the soil at the rates of 0, 1 and 2 mass percentages based on a factorial arrangement of the treatments in a completely randomized design with three replications. Biochar was prepared in a special furnace at 500°C without oxygen. The experiments were done with a flow rate of 4 liters per hour with the irrigation time of 3 hours. The results of the analysis of variance showed that the organic treatments increased the soil water content in the range of field capacity to a permanent wilting point; the highest increase was observed for the biochar 2% treated soil. Also, the addition of rice husk and biochar in the silty clay soil reduced the horizontal advance and increased the vertical advance wetting pattern.
H. Shabani, M. A. Delavar, S. T. Fardood,
Volume 24, Issue 1 (5-2020)
Abstract
Today, to reduce the risks of contaminants, new remediation techniques have been focused on low-cost and environmentally friendly manners. Given the frequency of access, inexpensiveness and good physical and chemical properties, biochar has a high potential for the remediation of water pollutants. In this paper, the efficiency of chitosan engineered biochar (Bc-Ch) and pristine biochar (Bg-Bc) prepared from sugarcane bagasse biomass (Bg) in the Cd2+ removal in aqueous solution was investigated. To this aim, the effects of contact time, adsorbent dosage and solution pH on cadmium removal were evaluated by adsorption isotherms and Kinetic models. The results indicated that the Langmuir isotherm and the pseudo-second-order kinetic model could be well fitted with the process of cadmium biosorption. The maximum adsorption capacities of Bc-Ch, Bg-Bc and Bg ,according to Langmuir model, were found to be 32/78 mg/g, 11/57 mg/g and 2/23 mg/g, respectively. For these absorbents, the pseudo-second-order kinetic model showed the best fit to the experimental adsorption data. This study, therefore, indicated that the chitosan engineered biochar could be used as an effective, low-cost, and environmentally-friendly sorbent to remediate heavy metals contamination in the environment.
Z. Noori, M. A. Delavar, Y. Safari,
Volume 24, Issue 4 (2-2021)
Abstract
The present study was intended to improve the chemical properties of a saline-sodic soil using the individual application of alfalfa residue and two biochars produced from sugarcane bagasse and walnut shell, at the weighting ratio of 5%; their concomitant application with gypsum, aluminum sulfate and the mixture of these two chemical amendments was considered. The experiment was conducted in three replications using the factorial experiment in a completely randomized design. After four months of incubation, the soil samples were measured for their main chemical properties. The results showed that alfalfa residues were the most effective treatment to reduce the soil pH; so the concomitant application of this organic amendment with gypsum lowered the soil pH from 9.13 in the control (untreated soil) to 7.24. It was also observed that the addition of gypsum and/or aluminum sulfate to the soil led to the increase of the soil electrolyte concentration and consequently, the increase of soil electrical conductivity to three times greater than control, through an increase of ions, like calcium and sulfate in the soil solution. Increasing the soluble sodium concentration by replacing exchangeable sodium by other similar ions showed that the studied treatments enhanced the sodium adsorption ratio (SAR), which could be regulated by washing. Concomitant application of the walnut-shell biochar with gypsum had the most increasing effect on the soil SAR, enhancing it from 22.6 in the control to 54.3. Potassium was released from organic amendments, improving the soil general conditions; addition of chemical amendments elevated soil exchangeable potassium contents; however, the elevated soil available phosphorus contents were less influenced by chemical amendments application. As the conclusion, it seems that the positive impacts of the applied chemical and organic amendments would supplement each other; as a result, the concurrent use of both treatments not only improves the bad soil chemical properties, but also enhances the soil fertility.
E. Mirzakhani, H. Motaghian, A. Hosseinpur,
Volume 25, Issue 4 (3-2022)
Abstract
Pollution of the environment by heavy metals, especially soil pollution with cadmium (Cd), is one of the most important environmental problems. Also, salinization of soils due to a decrease in irrigation water quality reduces plants growth. To investigate the effect of sugarcane bagasse biochars and salinity on Cd available and Cd fractions in a contaminated soil (15 mg kg-1 Cd), an experimental factorial design in a completely randomized design including (1) biochar factor with control, 1% (w/w) bagasse, 1% (w/w) biochar 400 °C and 1% (w/w) biochar 600 °C, and (2) salinity factor with control, 20, and 40 mmol kg-1 as sodium chloride were performed in 3 replications. The amount of available Cd was determined by the DTPA-TEA method and the Cd fractions were determined by Tessier et al. (1979). The results showed that biochar and salinity had no significant effect on soil pH (P > 0.05) but increased soil EC (P < 0.05). Interaction of biochar and salinity was not significant (P > 0.05) on available Cd and Cd fractions. Biochar application reduced Cd -DTPA-TEA (P < 0.05), whereas salinity increased Cd -DTPA-TEA (P < 0.05). Application of biochar prepared at 600 °C reduced (P < 0.05) exchangeable Cd (23.8%) and increased (P < 0.05) Cd associated with iron and manganese oxides (25.2%) and residual (15.6%) compared to the control. The results showed that salinity had no significant effect on the Cd fractions (P > 0.05) and soil treated with sugarcane bagasse biochar can reduce Cd available due to changing the Cd distribution from unstable forms to stable forms.
N. Azadi, F. Raiesi,
Volume 26, Issue 1 (5-2022)
Abstract
Biochar as an efficient strategy for the improvement of soil properties and organic waste management may reduce the potential effects of abiotic stresses and increase soil fertility. However, the effects of this organic amendment on soil microbial indicators under combined salinity and pollution have not been studied yet. Therefore, the objective of this study was to evaluate the influence of sugarcane bagasse biochar on some soil bioindicators in a Cd-polluted soil under saline and non-saline conditions. A factorial experiment was carried out with two factors, including NaCl salinity (control, 20 and 40 mM NaCl) and sugarcane bagasse biochar (soils unamended with biochar, amended with uncharred bagasse, 400 oC biochar, and 600 oC) at 1% (w/w) using a completely randomized design. Results showed that salinity increased the mobility of Cd (12-17%), and subsequently augmented its toxicity to soil microorganisms as indicated by significant decreases in the abundance and activities of the soil microbial community. Conversely, sugarcane bagasse biochar application reduced the concentration of soil available Cd (14-18%), increased the contents of soil organic carbon (89-127%), and dissolved organic carbon (4-70%), and consequently alleviated the effect of both abiotic stresses on soil microbial community and enzyme activity. In conclusion, this experiment demonstrated that the application of sugarcane bagasse biochar could reduce the salinity-induced increases in available Cd and mitigate the interaction between salinity and Cd pollution on the measured soil bioindicators.
F. Khafi, A.r. Hossienpour, H. Motaghian,
Volume 26, Issue 2 (9-2022)
Abstract
One of the significant factors affecting biochar properties is the pyrolysis temperature. This study aimed to investigate the effect of pyrolysis temperature on the properties and fractionation of Zn and Pb in biochars produced by sewage sludge. Biochars were prepared at temperatures of 300 to 700 °C and the physicochemical properties, availability, and fractionation of Zn and Pb were investigated. The results showed that pH, pHzpc, percentage of calcium carbonate, cation exchange capacity, specific surface area, and porosity in biochars were higher than in the feedstock. By increasing biochar production temperature, the mentioned properties increased. FT-IR revealed that the OH functional group is present in free form, either in the structure of C-OH and -COOH and aliphatic-CH2 groups in the sewage sludge. By converting sewage sludge to biochar, the intensity of these peaks decreased. In contrast, peaks representing complex aromatic structures appeared. The availability of Zn and Pb in biochar was reduced as compared to sewage sludge. The results of fractionation indicated that sewage sludge has bio-availability and toxicity of Pb and Zn. the amount of oxide and residual fractions of these two metals increased by converting sewage sludge to biochar at different temperatures. Therefore, it seems that biochar production from sewage sludge reduces the toxicity and bio-availability of Zn and Pb. Also, by incrementing the temperature of production, the bio-availability potential (bonding with organic matter), and non-toxicity (residual) of these metals increased.
I. Hasanpour, M. Shirvani, M.a. Hajabbasi, M.m. Majidi,
Volume 26, Issue 2 (9-2022)
Abstract
Low organic matter content and alkaline pH of calcareous soils in arid and semi-arid regions are the main reasons for the low nutrient availabilities for plants in these soils. One way to improve the chemical properties and fertility of calcareous soils is the application of organic substances such as biochar produced from pyrolysis of organic wastes. However, biochars have an almost predominant alkaline pH, which exacerbates plant nutrient deficiencies in calcareous soils when used for a long time. Pyrolysis of some organic wastes under controlled temperature conditions can lead to the production of acidic biochar. The effect of acidic biochars on several chemical properties of two calcareous soils in Isfahan province was investigated in the present study. Treatments included two types of biochar (pine cone and rice husk), three levels of biochar addition (one, three, and six percent), two types of soil (a sandy loam (Tiran) and a clay loam (Lavark)), and two incubation periods (one and six months). The results showed that applying biochar could slightly decrease soil pH but raised soil electrical conductivity. In addition, the amount of organic carbon, total nitrogen, and available concentration of manganese in all treatments and the concentrations of available phosphorus, potassium, iron, zinc, and copper in the most of treatments showed a significant increase compared to the control. Amending soil with biochar at a 6% rate caused the most significant changes in the measured parameters in both soil types. In general, the results of this study indicated that acidic biochar produced from pine cones and rice husk can be used as a suitable conditioner to improve the chemical properties and fertility of calcareous soils.
R. Mousavai, M. Rasouli Sadaghiani, E. Sepehr, M. Barin,
Volume 27, Issue 1 (5-2023)
Abstract
can provide useful information about P adsorption and the factors affecting it. A batch experiment was performed with phosphorus concentrations (0 to 35 mg/L) in two soils with different electrical conductivity (EC) (2 and 15 dSm-1) by a variety of biochar treatments including simple apple-grape biochar (BC), rock phosphate- biochar (BC-RP), enriched-biochar (BC-H3PO4-RP), enriched-biochar (BC-HCl-RP), triple superphosphate (TSP), and control (Cont). The results indicated that phosphorus sorption capacity varied between the soils. Biochar treatments were effective in reducing the phosphorus adsorption of both soils. Due to BC-H3PO4-RP and BC-HCl-RP treatments, the maximum phosphorus adsorption of soils decreased in S1 soil by 14 and 23 % and in S2 soil by 26 and 19%, respectively. Also, the use of these treatments decreased the parameters of Langmuir absorption intensity (KL) of S1 soil to 0.085 and 0.066, respectively and S2 soil to 0.11 and 0.15, L/mg respectively, and Freundlich absorption capacity (KF) of S1 soil decreased to 19.2 and 22.5 and S2 soil to 28.2 and 28.1 L/kg, respectively. Enriched biochars significantly reduced the buffering indices of both soils indicating phosphorus adsorption decreased and increased the availability of phosphorus for the plant. The standard phosphorus requirement of S2 soil was lower than S1 soil by both equations. Therefore, enriched biochar can be an effective strategy to increase phosphorus availability and reduce the use of chemical fertilizers in saline and non-saline conditions; however, more field studies are needed for a clear understanding of the potential of P-enriched biochar as a fertilizer alternative.
E. Mirzakhani, H.r. Motaghian, A.r. Hosseinpur,
Volume 27, Issue 3 (12-2023)
Abstract
In addition to the distribution of elements in the soil solid phase, element species in the solution are also very important due to their importance of providing elements for root uptake. For a deeper study of the chemical cycle of elements in saline soils treated with biochar, the study of speciation is very useful and provides a method to reduce or transform the toxicity caused by toxic elements in saline soils. Therefore, to investigate the effect of biochar on Cd speciation in two saline calcareous soils, 15 mg kg-1 Cd as cadmium chloride was added to the soil sample (200 g), and the soils were incubated for three weeks at 25±2 °C at 80% field capacity. After the incubation period, salinity levels of 20 and 40 mmol kg-1 as sodium chloride (equal to 3.65 and 7.30 dS m-1) were added to the soils. Then, the 1% (w/w) of the sugarcane bagasse and biochars produced at 400 and 600 °C were added to the soils, and then incubated for three months at 25±2 °C at 80% field capacity. At the end of the incubation period, for the speciation of Cd in the soil solution (in a 1 to 2 ratio), the concentration of dissolved cations and anions in the soil samples was measured. The results showed that the interaction between salinity, biochar, and soil on Cd2+, CdCl+, CdCl20, and Cd(SO4)22- was significant. The application of biochar in sandy soil reduced (p <0.05) the concentration of CdCl+, CdCl20, CdSO40, and CdOH+ species compared to the control soil, while it did not affect clay soil. Also, salinity caused by sodium chloride in sandy soil increased the concentration of CdCl+ and CdCl20 species and decreased CdSO40 and CdOH+ species compared to the control soil (p <0.05). The results showed that biochar in saline sandy soil was more effective than clay soil in reducing Cd toxicity.
R. Hosseinpour, H.r. Asgari, H. Nikanhad Qermakher, E. Malekzadeh, M.k. Kianian,
Volume 27, Issue 4 (12-2023)
Abstract
The soils of desert areas are mostly low in organic matter and may fluctuate greatly in terms of acidity. Biochars are one of the materials used to improve and modify some soil characteristics. This compound is very resistant to decomposition and remains in the soil for a longer period, reducing agricultural waste and turning it into a soil conditioner. This leads to keeping carbon in the soil, increasing food security, increasing biodiversity, and reducing deforestation. In this research, an attempt was made to investigate the biochar of fodder beet plant waste produced at different pyrolysis temperatures and its physical and chemical characteristics. For this purpose, fodder beet wastes were collected from settlements around Birjand and after being crushed and air-dried, they were pyrolyzed in an electric furnace under limited oxygen conditions at a temperature range of 300-700 degrees Celsius. Then, the characteristics of the produced biochars were performed with 3 repetitions of measurements and statistical analyses with SPSS software. The results of this research showed that the characteristics of biochars changed significantly with temperature change. The highest yield percentage (59%), organic carbon (56.33%), total nitrogen (0.53%), water retention (0.84g/g) at 300 and 400 degrees Celsius, and the highest amount of ash (% 76), acidity (8.21) and electrical conductivity (0.1ds/cm) was obtained at a temperature of 700 degrees Celsius. The percentage of carbon and the efficiency of biochar produced at temperatures of 300 and 400 degrees Celsius were higher than other biochar produced at other temperatures. Biochar produced at 300°C has better characteristics in terms of carbon percentage and acidity efficiency compared to biochar produced at 400°C. Although these differences were not statistically significant, due to biochar production being more economical in terms of energy consumption, it is recommended to produce biochar at a temperature of 300 degrees Celsius.
