Effects of Three Biochars as Adsorbents on Soils Adsorbing Ammonium Nitrogen in Biogas Slurry

The increasing concern of biogas slurry disposal and nitrogen loss in soils has brought back the interest in using biochar as an adsorbent of biogas slurry in soils. Three types of biochars, commercial activated carbon, pyrolysis productions derived from rice husk, and nut shell, were added as adsorbents in two types of soils (sandy and loamy) at solid weight ratio of 5%, 10%, 15%, and 20% to investigate the effects of biochars on soils adsorbing ammonium nitrogen (NH4+-N) in biogas slurry using oscillation method. There was no difference of NH4+-N adsorbability for sand soil and loamy soil. The NH4+-N adsorption capacity of soils increased as the additive biochars increased from 0 to 20%. The smaller particle size of biochars led to the shorter stable adsorption time and the better NH4+-N adsorption capacity. Commercial activated carbon showed the best NH4+-N adsorption capacity in biogas slurry, followed by the nut shell carbon. The rice husk carbon was the worst. The results in this study provide a feasible and cost-effective assessment method of biochars for increasing the NH4+-N adsorption capacity of soils in biogas slurry, as well as good insight into effects of different biochars on improving NH4+-N adsorption capacity of soils.

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Analisis Variasi Temperatur Aktivasi Terhadap Daya Serap Arang Aktif Tandan Aren (Arenga Pinnata Merr) Dengan Agen Aktivasi Potassium Silicate(K2SiO3)

Jurnal Penelitian Pendidikan Fisika ◽

10.36709/jipfi.v5i3.13803 ◽

2020 ◽

Vol 5 (3) ◽

pp. 221

Author(s):

Muhammad Azam ◽

Muhammad Anas ◽

Erniwati Erniwati

Keyword(s):

Methylene Blue ◽

Activated Carbon ◽

Adsorption Capacity ◽

Temperature Variation ◽

Chemical Activation ◽

Weight Ratio ◽

Potassium Silicate ◽

Physical Activation ◽

Activation Temperature ◽

Pyrolysis Reactor

This study aims to determine the effect of variation of activation temperature of activated carbon from sugar palm bunches of chemically activatied with the activation agent of potassium silicate (K2SiO3) on the adsorption capacity of iodine and methylene blue. Activated carbon from bunches of sugar palmacquired in four steps: preparationsteps, carbonizationstepsusing the pyrolysis reactor with temperature of 300 oC - 400 oC for 8 hours and chemical activation using of potassium silicate (K2SiO3) activator in weight ratio of 2: 1 and physical activation using the electric furnace for 30 minutes with temperature variation of600 oC, 650 oC, 700 oC, 750 oC and 800 oC. The iodine and methyleneblue adsorption testedby Titrimetric method and Spectrophotometry methodrespectively. The results of the adsorption of iodine and methylene blue activated carbon from sugar palm bunches increased from 240.55 mg/g and 63.14 mg/g at a temperature of 600 oC to achieve the highest adsorption capacity of 325.80 mg/g and 73.59 mg/g at temperature of 700 oC and decreased by 257.54 mg/g and 52.03 mg/g at a temperature of 800 oCrespectively.However, it does not meet to Indonesia standard (Standard Nasional Indonesia/SNI), which is 750 mg/g and 120 mg/g respectively.

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Modeling and Optimization for Production of Rice Husk Activated Carbon and Adsorption of Phenol

Journal of Engineering ◽

10.1155/2014/278075 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Y. S. Mohammad ◽

E. M. Shaibu-Imodagbe ◽

S. B. Igboro ◽

A. Giwa ◽

C. A. Okuofu

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Removal Efficiency ◽

Rice Husk ◽

Adsorption Process ◽

Operating Conditions ◽

Optimum Operating ◽

Process Variables ◽

Adsorbent Dosage ◽

Pretreatment Temperature

Modeling of adsorption process establishes mathematical relationship between the interacting process variables and process optimization is important in determining the values of factors for which the response is at maximum. In this paper, response surface methodology was employed for the modeling and optimization of adsorption of phenol onto rice husk activated carbon. Among the action variables considered are activated carbon pretreatment temperature, adsorbent dosage, and initial concentration of phenol, while the response variables are removal efficiency and adsorption capacity. Regression analysis was used to analyze the models developed. The outcome of this research showed that 99.79% and 99.81% of the variations in removal efficiency and adsorption capacity, respectively, are attributed to the three process variables considered, that is, pretreatment temperature, adsorbent dosage, and initial phenol concentration. Therefore, the models can be used to predict the interaction of the process variables. Optimization tests showed that the optimum operating conditions for the adsorption process occurred at initial solute concentration of 40.61 mg/L, pretreatment temperature of 441.46°C, adsorbent dosage 4 g, adsorption capacity of 0.9595 mg/g, and removal efficiency of 97.16%. These optimum operating conditions were experimentally validated.

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Impregnating Activated Carbon with Iron Salts to Increase Hydrogen Sulfide Removal

UF Journal of Undergraduate Research ◽

10.32473/ufjur.v20i2.106174 ◽

2019 ◽

Vol 20 (2) ◽

Author(s):

Morgan Hull

Keyword(s):

Hydrogen Sulfide ◽

Activated Carbon ◽

Adsorption Capacity ◽

Cost Effective ◽

Heat Treatments ◽

Time Duration ◽

Hydrogen Sulfide Removal ◽

Iron Salts ◽

Heat Treated ◽

Removal Technologies

Hydrogen sulfide (H₂S) emissions from landfills negatively impact surrounding communities. In addition to an unpleasant, rotten-egg odor, inhalation of the gas can cause respiratory distress and irritation. Peak emissions are released from C&D landfills through the decomposition of gypsum drywall. Current removal technologies are costly and often ineffective. The goal of this research was to develop a cost-effective mat geared toward H₂S removal. Preliminary research revealed an increase in adsorption capacity through the addition of iron salts, FeCl3 and FeSO4, to activated carbon at a 5:1 carbon to iron ratio. To evaluate the effect of heat treatments on iron oxide formation, and subsequent adsorption capacity, samples were divided into heat treatment groups of 250ºC, 450ºC, and 650ºC. Samples were flushed with 100 ppm of H₂S under N₂ at 250 ml/min for two hours. Over this time duration, samples subjected to higher temperature heat treatments showed increased adsorption capacity. All heat treated samples demonstrated higher adsorption compared to the baseline non-heat treated samples. Additional research will be conducted to assess the effect of heat treatments above 650ºC.

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SURFACE MODIFICATION OF ACTIVATED CARBON FROM RICE HUSK FOR ENHANCING THE NICKEL(Ni2+) AND CADMIUM (Cd2+) ADSORPTION CAPACITY

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/54/4b/12019 ◽

2018 ◽

Vol 54 (4B) ◽

pp. 19

Author(s):

Hoa Thai Ma

Keyword(s):

Surface Modification ◽

Activated Carbon ◽

Reaction Time ◽

Optimal Condition ◽

Adsorption Capacity ◽

Rice Husk ◽

High Surface ◽

Control Sample ◽

Equilibrium Concentration ◽

Modification Process

Activated carbon (AC) has been proven to be an effective adsorbent for the removal of a variety of pollutants. AC is extensively used for adsorption because its high surface area is well-developed internal micro porosity. The objective of this study is to determine the optimal condition of the surface modification process of activated carbon from rice husk (ACRH) using HNO3. That increase the functional group, and improve affinity towards certain contaminants of ACRH for increasing the adsorption capacity of Ni2+ and Cd2+. Two factors were taken into account as: the concentration of HNO3 (1, 3, and 5 M), reaction time (1, 2, 3, 4 and 5 hours). The results showed that the optimal condition of the surface modification process was derived at the equilibrium concentration of HNO3 = 3 M and the equilibrium reaction time = 4 hour. Interestingly, in comparison with the control sample (ACRH not modified), the adsorption capacity of Ni2+ and Cd2+ increased from 10.0 to 17.2 mg/g and 10.4 to 29.6 mg/g, respectively. This adsorption capacity of modified ACRH shows the increase significantly.

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The Potentiality of Rice Husk-Derived Activated Carbon: From Synthesis to Application

Processes ◽

10.3390/pr8020203 ◽

2020 ◽

Vol 8 (2) ◽

pp. 203 ◽

Cited By ~ 7

Author(s):

Md Masruck Alam ◽

Md Ashraf Hossain ◽

Md Delowar Hossain ◽

M.A.H. Johir ◽

Jewel Hossen ◽

...

Keyword(s):

Activated Carbon ◽

Rice Husk ◽

Organic Contaminants ◽

High Surface ◽

High Surface Area ◽

Cost Effective ◽

Industrial Applications ◽

Catalytic Support ◽

Energy Applications ◽

Effective Synthesis

Activated carbon (AC) has been extensively utilized as an adsorbent over the past few decades. AC has widespread applications, including the removal of different contaminants from water and wastewater, and it is also being used in capacitors, battery electrodes, catalytic supports, and gas storage materials because of its specific characteristics e.g., high surface area with electrical properties. The production of AC from naturally occurring precursors (e.g., coal, biomass, coconut shell, sugarcane bagasse, and so on) is highly interesting in terms of the material applications in chemistry; however, recently much focus has been placed on the use of agricultural wastes (e.g., rice husk) to produce AC. Rice husk (RH) is an abundant as well as cheap material which can be converted into AC for various applications. Various pollutants such as textile dyes, organic contaminants, inorganic anions, pesticides, and heavy metals can be effectively removed by RH-derived AC. In addition, RH-derived AC has been applied in supercapacitors, electrodes for Li-ion batteries, catalytic support, and energy storage, among other uses. Cost-effective synthesis of AC can be an alternative for AC production. Therefore, this review mainly covers different synthetic routes and applications of AC produced from RH precursors. Different environmental, catalytic, and energy applications have been pinpointed. Furthermore, AC regeneration, desorption, and relevant environmental concerns have also been covered. Future scopes for further research and development activities are also discussed. Overall, it was found that RH-derived AC has great potential for different applications which can be further explored at real scales, i.e., for industrial applications in the future.

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Designing, Implementation and Evaluation of an E-portfolio for Assessment of Surgical Technologist Students in Iran: a Mixed Method Study

10.21203/rs.3.rs-801093/v1 ◽

2021 ◽

Author(s):

Leila Sadati ◽

Sahar Karami ◽

Rana Abjar ◽

Mehdi Tayebi-Arasteh ◽

Fatemeh Edalat ◽

...

Keyword(s):

Clinical Skills ◽

Portfolio Assessment ◽

Critical Role ◽

Cost Effective ◽

Assessment Method ◽

Design Stage ◽

Clinical Settings ◽

Professional Goals ◽

Evaluation Stage ◽

Effective Assessment

Abstract Background: Building a portfolio is an appropriate method for assessing competency and practice in clinical settings. Portfolio assessment provides opportunities for students to reflect on their performance and therefore could have a critical role in observing students' progress and developing competencies. With the emphasis of modern medical education on e-portfolios, the present study was done to design, implement, and evaluate an electronic portfolio to assess surgical technologist students learning in Iran.Methods: This mixed study was conducted in three stages: "designing," "implementation," and "evaluation." The "design" stage included a literature review, the completion and modification of the list of portfolio items, and content approval by experts. The "implementation" stage involved loading the system, holding workshops for students and clinical preceptors. Finally, the "evaluation" stage included assessing preceptors' and students' satisfaction, knowledge, and clinical skills and recording the number of reflections. Results: The paired sample t-test result shows that students' knowledge and clinical skills significantly improved. More than two-thirds of the students and preceptors were thoroughly satisfied with the e-portfolio assessment. On average, each student had more than three reflections recorded.Conclusions: Using an e-portfolio assessment satisfies students and preceptors, improves surgical technologist students' knowledge and skills, and supports their progress toward achieving professional goals; therefore, it is recommended as a comprehensive and cost-effective assessment method.

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EFFECT OF THE CARBONIZATION AND ACTIVATION PROCESS ON THE ADSORPTION CAPACITY OF RICE HUSK ACTIVATED CARBON

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/55/4/9124 ◽

2017 ◽

Vol 55 (4) ◽

pp. 494 ◽

Cited By ~ 5

Author(s):

Hoa Thai Ma ◽

Hung Cam Ly ◽

Van Thi Thanh Ho ◽

Nguyen Bao Pham ◽

Dat Chi Nguyen ◽

...

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Rice Husk ◽

Raw Materials ◽

Internal Surface ◽

Surface Characteristics ◽

Bet Surface Area ◽

Adsorptive Capacity ◽

Physical Activation ◽

Activation Process

In this study, rice husk was used as a precursor to prepare activated carbon using steam as a physical activation agent. Steam for activation can be used to activate almost all raw materials. A variety of methods have been developed but all of these share the same basic principle of initial carbonization followed by an activation step with steam. The study also investigates the effects of preparation parameters on the surface characteristics of the carbon. These parameters include the range of temperature and time in the carbonization and activation. The initial carbonization, done at temperatures up to 500°C in 60 min, is a highly exothermic process where the temperature is strictly controlled. The creation of the internal surface is done during the activation step with steam at temperatures 800°C in 30 min., for which the BET surface area is up to 710.8m2/g. Besides, the iodine and methylene blue adsorption capacity of rice-husk carbon are the best that reach 865.98±6.5 and 217.86±1.0 (mg/g), respectively. The entire synthetic procedure was simple, environmental-friendly and economical-effectively. The application prospect of the activated carbon prepared in this work was much more promising due to its high adsorptive capacity.

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Determination of rice husk activated Carbon capacity in adsorption of Cu Metal from Sasirangan liquid waste based on isotherm model

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1212/1/012019 ◽

2022 ◽

Vol 1212 (1) ◽

pp. 012019

Author(s):

I Syauqiah ◽

D Nurandini ◽

N P Prihatini ◽

Jamiyaturrasidah

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Rice Husk ◽

Langmuir Isotherm ◽

Liquid Waste ◽

Isotherm Model ◽

Isotherm Models ◽

Synthetic Dyes ◽

Isotherm Equation ◽

Adsorption Data

Abstract The process of manufacturing Sasirangan - a traditional fabric of South Kalimantan - has an impact that affects environmental pollution, namely the dyeing process of the fabric. The synthetic dyes used contain heavy metals and one of those toxic metals is copper (Cu). This study aims to determine the adsorption capacity of rice husk activated carbon adsorbent by adjusting the adsorption pattern based on isotherm models as the treatment to sasirangan liquid waste. The method consists of three stages: preparation of adsorbent by carbonization process, chemical and physical activation, then continued by adsorption process of Cu metal with carbon from rice husks with variations of adsorbent dose (2, 4, and 6 grams). This treatment was conducted by batch process. In this reseach, the adsorption capacity of rice husk adsorbent towards heavy metal Cu in sasirangan liquid waste was determined from the equilibrium state with the Langmuir isotherm equation and Freundlich isotherm equation. Based on isothermal studies of adsorption data, the correlation coefficient values obtained from the isotherm model approaches are: for dose of 2 grams adsorbent, Langmuir R2 = 0.9991 and Freundlich R2 = 0.9981; for dose of 4 grams adsorbent, Langmuir R2 = 0.9992 and Freundlich R2 = 0.9989; for dose of 6 grams adsorbent, Langmuir R2 = 0.9990 and Freundlich R2 = 0.9986. The results of investigation indicate that adsorption data correlated well with Langmuir isotherm model.

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Adsorption of Mercury Ion on Activated Carbons from Rice Husk

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.161.162 ◽

2012 ◽

Vol 161 ◽

pp. 162-166 ◽

Cited By ~ 1

Author(s):

Xiao Lan SONG ◽

Ying Zhang ◽

Cheng Yin Yan ◽

Wen Juan Jiang ◽

Hong Jiang Xie

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Rice Husk ◽

Activated Carbons ◽

Langmuir Model ◽

Mercury Ion ◽

Maximum Adsorption Capacity ◽

Adsorption Performance ◽

Monolayer Adsorption ◽

Adsorption Data

The adsorption performance of mercury ion onto activated carbon prepared from rice husk with NaOH was carried out at initial concentration of 100 mg/L. The activated carbon obtained at 800 °C possessed the outstanding specific surface area of 2786 m2/g. And the results showed that the maximum adsorption capacity of Hg2+ was recorded as 342.0 mg/g due to abundant micropores of 1.076 nm. In addition, the adsorption data were well explained by the Langmuir model with the monolayer adsorption capacity of 555.6 mg/g.

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