Rice Husk Combustion Research Articles

THE IMPACT OF RICE HUSK ASH (RHA) AS SOILLESS GROWING MEDIUM ON SAWI CAIXIN GIANT (Brassica parachinensis) GROWTH PERFORMANCE

The Sustainable Development Goal 2 (SDG 2), which aims to end hunger, enhance nutrition, and support sustainable agriculture, places a high priority on food security. The amount of rice husk ash (RHA) produced by the process of burning rice husks has increased over time, causing environmental pollution. In modern soilless agriculture, RHA has a significant potential to be used as a fertile and nutrient-rich medium. The Zero Energy Soilless Agriculture (ZESA) System is a revolutionary concept for horticultural plants that might utilize RHA as a soilless growing medium. The effect of growing medium ratio of cocopeat and RHA on plant growth performance of sawi caixin giant (Brassica Parachinensis) using ZESA system over 35 days was investigated in this study. Three different treatments, T1 (1:0), T2 (1:1), and T3 (3:1), on the growing medium ratio of cocopeat and RHA were carried out. The treatments were set up in four replicates of two individuals each using a randomised full block design. The data of plant Growth parameters such as the number of leaves and plant height were recorded every 7 days, and the fresh weight of the plants was taken on harvesting day. FTIR analysis and an elemental analyzer were used to characterise the chemical analyses of cocopeat, RHA, and fertiliser. As shown by the results, T3 treatment increased all plant growth performance parameters compared to T1 control treatment, with a value of 12.02 cm for plant height, 10 leaves, and 33.75g of fresh weight. The plant growth performance of Brassica parachinensis was improved by using a 3:1 ratio of 25% RHA as a soilless growing medium couple with application of rich nitrogen X and Y fertilisers using the ZESA System. Finally, RHA has the potential to be used as a soilless growing medium for many horticulture plants using the ZESA System.

Disentangling the effects of rice husk ash on increased plant growth and nitrogen recovery

Rice production generates large quantities of residues, whose disposal can pose environmental and health risks when not managed properly. The residue after rice husk combustion for energy production, rice husk ash (RHA), is currently underutilized despite its great potential as a soil conditioner. We aim to test the impact of RHA application on wheat growth, functional characteristics of the soil nitrifiers community and on N recovery using a 15N tracing greenhouse experiment. To distinguish between the effects caused by its liming capacity and P content, liming and P application treatments were included in the experiment. The amelioration of soil acidity (by both lime and RHA) lead to reduced losses of applied N fertilizer, but only RHA improved plant growth and plant N uptake. On the other hand, unlike RHA, lime application had strong effect on nitrification, increasing the potential maximal nitrification capacity (NEA) and reducing the affinity for N-NH4+ of soil nitrifiers (NHScom). The application of P reduced losses of applied 15N fertilizer particularly in the control pots, where additional P supply was likely critical to enhance N utilization by soil microorganisms. We therefore conclude that RHA effects on studied parameters are not only caused by soil pH amelioration nor by the P supply, but are likely driven by other inherent RHA properties (such as for instance its high content of macro- and micronutrients). The lack of observed effects on nitrification parameters and enhanced plant growth after RHA application can lead to considerably lower N losses and higher C sequestration in comparison to liming, while helping to solve the problems linked with RHA disposal.

Effect of growing media on growth and flowering of potted marigold (Tagetes erecta L.) irrigated with treated sewage water

The present study was undertaken with an objective to evaluate the effect of different soil-based and soilless growing media compositions supplemented with treated municipal sewage water and tap water in different ratios on growth and flowering of potted marigold. The experiment was conducted in a completely randomized block design comprising four media substrates (Soil, burnt rice husk [BRH], farmyard manure [FYM] and cocopeat [CP]) mixed in four different proportions (M1 to M4) and five irrigation levels (I1 to I5) of different combinations of tap water (TW) and treated sewage water (TSW). Results revealed that the media substrate composition (M4) comprising CP + BRH + FYM (25:25:50) was found to be suitable for sustaining the growth of potted marigold plants. The media had relatively higher percent N, P & K with acceptable pH and EC. The marigold plants raised in M4 media irrigated with TSW (100%) preformed significantly well for vegetative and floral characters, essential for a specimen display without any visual phytotoxicity symptoms. Number of flowers per plant and days to flowering duration were observed significantly higher in M4 compared to other media treatments. The analysis of TSW (100%) revealed higher N (0.91 ppm), P (1.67 ppm), K (24.13 ppm) with pH (7.73) and EC (2.10 ds m−1) in acceptable range.

A preface to agricultural wastes as sustainable construction material

Cement is inevitable to construction industry due to its excellent binding property. The cement production results in excessive consumption of natural resources, which tends to their depletion. Thus, the production of cement is an energy demanding procedure. The extraction and making process of 1 ton cement expels around a ton of CO2 gas to the environment. Rice husk ash (RHA) is generated by the burning of rice husk at a high temperature. The by-product of rice grinding industry is termed as rice husk. Sugarcane bagasse ash (SBA) is obtained by burning the by-product of sugar industry. The disposal of the former results in severe environmental problems. RHA and SBA are observed as the commonly used agricultural wastes in cementitious system. This study reviews the potential of RHA and SBA as a construction material. The study evaluates the application of RHA and SBA as supplementary cementitious materials. The hardened and durability performance of cement mortar or concrete has been reviewed and observed that the agricultural waste incorporated construction materials exhibit good mechanical and durability properties.

Production of new generation and sustainable concrete using Rice Husk Ash (RHA): A review

Rice husk is an agricultural by-product available in huge quantities, particularly in India. This is an appropriate biomass source for the production of energy. Compared to other agricultural by-products like sugar cane bagasse, the burned rice husk yields nearly 20% of ash, with the chief constituent of silica that will be typically amorphous when properly burned. Wide-ranging research in the last two decades has permitted the use of Rice Husk Ash (RHA) as a supplementary cementitious material (SCM) in cement-based products, whereby significant enhancements in strength and durability properties can be accomplished. From published literature, it has been found that this bio-based material is possessing high pozzolanic properties which have made this a novel technology because of the green nature of the exercise. The CO2 emission with the utilization of RHA is zero. Hence, a partial replacement of OPC in cement composites with this cementing additive is a breakthrough for our environment with improved sustainability. This paper discussed the state-of-the-art pozzolanic behavior of RHA, its Physio-chemical characteristics, and its influence on the mechanical and durability properties of cementitious composites. The outcome of the review helps in fulfilling the massive burdens on the construction industry economically and sustainably.

QUALITY AND SUITABILITY OF SOILS OF NORTHERN EBONYI, SOUTHEASTERN NIGERIA FOR RICE PRODUCTION

This study was carried out in Abakaliki region, Ebonyi state of southeastern Nigeria and aimed at studying the quality and suitability of soil used for rice cultivation in the area between 2015 to 2017. This purpose was necessary due to the dwindling yield of rice in northern Ebonyi, southeastern Nigeria leading to increased hunger in the country and daunting the efforts of the government to achieve her goal of food security by the year 2025. Soils were delineated into upland, lowland and irrigated as different rice farming land uses with three profile pits dug in each location amounting to a total of nine (9) profile pits for the study. Soil quality indicators employed were; climate, soil physical condition, wetness, fertility and toxicity. An index of productivity equation was used to calculate the suitability status of each of the studied locations. The three pedons of upland rice soils were not suitable (N1) for rice production, while pedons 1 of the lowland and 2 of the irrigated were marginally suitable (S3) while others in these locations were not suitable (NI). The major challenges faced by these soils were basically of wetness, fertility and toxicity. All other soils at the lowland and irrigated soils were not suitable (NI). Practices that will conserve the fertility status of these soils should be adopted such as rotational farming, accumulation of organic materials on the soils and avoidance of burning of rice husks. This is necessary as fallow practice does not exist anymore due to demographic pressure and population growth in southern Nigeria.

Strength and micro-structural performance of geopolymer concrete using highly burned rice husk ash

Globally, many researchers use rice husk ash as a supplementary material in cement and geopolymer concrete. pozzolanic admixture. However, silica is insufficient for effective pozzolanic reaction in cement concrete and geopolymerization in geopolymer concrete. Therefore, choosing silica in the amorphous form is the primary objective, particularly agro-based as a precursor. Therefore, this experimental study was to synthesize geopolymer from rice husk ash (RHA) collected from a brick kiln and fly ash to utilize both materials effectively. In this study, the material characterization of both precursors was studied, and it was observed that RHA has desirable qualities as a precursor along with fly ash. The effects of adding RHA (0–20 by weight in percentage) to fly ash geopolymer concrete were examined. The partial inclusion of RHA content increased the compressive strength of the fly ash geopolymers. The very persistent and amorphous silica phase in the geopolymer concrete was primarily responsible for the enhancement of the geopolymer matrix. Because it was dissolved in the alkaline-activated solution, the amorphous silica significantly aided in the geopolymerization process. Although fly ash particles were still present in the geopolymer matrix, the unreacted fly ash particles did not add strength. However, performance would be better if the RHA content were more than 15% in the geopolymer concrete. The results presented in the study highlight the significant benefits of highly burned rice husk ash: it enhances geopolymerization and strength. Therefore, such in-depth investigation is imperative to judge the applicability of an appropriate form of RHA to attain higher strength and micro-structural performance.

Sustainable concrete interlock tile using rice husk ash & EVA polymer

One-third of the weight of paddy is made up of rice husk, an agricultural waste product created during the grinding of paddy. In developing and undeveloped nations, rice husks are frequently used as fuel for industrial applications because they have a high calorific value. Rice Husk Ash (RHA), obtained by the combustion of Rice husk contains amorphous silica and has shown excellent performance when used as a pozzolanic material in concrete. Ethylene Vinyl Acetate (EVA) is a polymer and millions of tonnes of EVA are produced in the form of powder, large-scale EVA production, or post-consumer products around the world. EVA is widely used in the footwear and apparel industries because of its outstanding balance of low cost, good processability, lightweight, and shock absorption qualities. It is employed in the footwear industry to create enlarged plates used for stamping insoles, midsoles, and soles. Thus, the EVA waste generated by the footwear industry causes huge environmental pollution concerns. An eco-friendly lightweight concrete interlock tile was prepared to address the environmental issues caused by EVA waste and Rice husk ash. The paper shows a detailed technical study of the execution of the developed combined concrete and interlock tile. The test results stipulated that the strength and the workability of the developed concrete were not as promising as we expected. Still this work can be considered an effective step towards addressing the problems caused due to waste EVA and Rice Husk Ash. Also, the interlock produced can be used in places where there is light traffic.

Effect of mechanical activation on the properties of rice husk ash-based one part geopolymer

Geopolymer concrete is an eco-friendly alternative to OPC because of its low carbon footprint. Being a “no cement” concrete, it is having great potential to offset the environmental impacts caused by ordinary Portland cement. The spectrum of uses for GPC is significantly influenced by the characteristics of the binder which should be rich in silica and alumina. Rice Husk Ash (RHA) is an agricultural waste byproduct obtained from the combustion of rice husk under controlled temperatures. Since it is produced in large quantities, the disposal of RHA is extremely difficult for waste management. This study examines how the mechanical activation of rice husk ash affects the physical, mechanical, and microstructural characteristics of one-part geopolymer concrete with rice husk ash. A mixture of rice husk, sodium hydroxide, sodium metasilicate, and aluminium oxide was ground in a ball mill for 2, 4, and 6 h to create one part geopolymer. XRD was used to characterize the powder. Workability was assessed using the slump test, and compressive strength was used to assess the mechanical property. Mechanical activation resulted in the creation of a more amorphous structure, according to XRD. For a six-hour ground sample, the greatest compressive strength of 32 MPa was attained.

Experimental studies of the strength of fine-grained concrete with implementations of organomineral additives

Experimental studies of the strength of fine-grained concrete with implementations of organo mineral additives were carried out. The organo mineral additive in the amount of 5-15% by weight of cement has a significant effect on the strength characteristics. Zeolite-containing rock with a specific surface area of 4000 cm2/g was used in the studied compositions. The amount of water added to the mixture also increases with an increase in the amount of organo mineral additive in the concrete mixture. The introduction of an organo mineral additive as a mineral additive instead of a part of the cement promotes the pozzolanic process, in which amorphous silica (SiO2) is bound to the lime formed during cement hydration as a result of the transition to down-basic hydro silicates. The addition of zeolite-containing rocks in an amount of 5-15% by weight of cement has a significant effect on the strength characteristics. The greatest increase in compressive and flexural strength is achieved by replacing 10% cement with TPP ash (heat from a power plant). It was established that a 10% dosage of TPP ash is optimal and is used for a further selection of the composition of fine-grained concrete. The resulting mixture has increased workability and plasticity. The most optimal dosage of additives is 1-1.5%. As the second mineral additive, we used an additive of technogenic origin - microsilica, i.e. ash from burning rice husks. After studying the literature, it was concluded that the addition of microsilica in an amount of 10-12% by weight of cement most contributes to increasing the strength of concrete. The research work is aimed at improving the properties of cellular concrete, developing their composition and production technology by introducing minerals and modifying additives. The results of the research work provide an increase in manufacturability, strength, water and frost resistance, and operational reliability of the obtained materials. The joint implementation of ash and a chemical mixture into fine-grained concrete allows concluding that the strength indicators increase, and the water-cement ratio and porosity decrease.

Influence of Composition of Soilless Substrates Monitored with Iot Sensor Nodes on the Growth, Nutrient and Fruit Quality of Rockmelons (Cucumis melo Var. Cantalupensis)

Background: Coconut coir dust (CD) is commonly used for growing selected fruit and vegetables. It is a soilless medium with excellent drainage and high-water holding capacity; free from infestations of weeds and pathogens. However, plant growth is adversely affected due to its high salinity, potassium and low pH. Methods: A greenhouse experiment was conducted to investigate the influence of different soilless media on rock melon’s growth, nutrient and fruit quality. Five soilless media were prepared including CD as control. A customised portable IoT system was deployed to monitor and collect relevant real-time agronomic data. Result: Plant height, yield, leaf area, total fresh fruit weight and soluble solids content (sweetness) of rock melon were significantly affected by the growing medium. Among the five media used, the growth and quality characteristics were highest in M2 followed by M3. It was found that a combination of burnt rice husk (BRH) and perlite with CD remarkably improved the growth of fruit quality of rock melon.

Rice Husk Waste: Impact on Environmental Health and Potential as Biogas

Indonesia is an agricultural country with dry-milled grain production reaching 55.6 million tons in 2022. Besides producing an abundance of rice, milled dry rice also results in waste in the form of rice husks. The handling of rice husk waste is mostly by burning. The smoke from burning is toxic, so it has a poor impact on environmental health. This study is regarding the effect of improper management of rice husks on environmental health, the utilization of rice husks in biogas energy, and its potential in Indonesia. Air quality measurement in areas burning rice husks on the parameters SO2, CO, NO2, and PM10 regarding the method of the Indonesian National Standard. Then anaerobic laboratory-scale research to convert rice husk into biogas. Chemical pretreatment was carried out with 3% NaOH and the C/N ratio determined was 25. Condition variations were determined for L-AD with 7% TS and SS-AD with 17% TS. We found that burning rice husks harm on environmental health. It is indicated by the SO2 and PM10 parameters exceeding the quality standards, namely 167 and 132 µg/m3.The NO2 parameter almost reached the quality standard, namely 178 µg/m3. Generated rice husk can be converted into renewable energy in biogas with good productivity in SS-AD conditions, with biogas production reaching 75.2 mL.gTS-1. Biogas potential from rice husks reached 1.5 million liters. It can support energy security for Indonesia.

Introducing a Novel Rice Husk Combustion Technology for Maximizing Energy and Amorphous Silica Production Using a Prototype Hybrid Rice Husk Burner to Minimize Environmental Impacts and Health Risk

Rice husk is the main by-product of the postharvest stage in rice production, which causes environmental impacts due to improper management as a solid waste. However, potential economic applications of rice husk combustion have been identified for energy generation and amorphous silica production in several industries. To minimize hazardous gaseous emissions and crystalline silica availability, rice husk combustion conditions should be properly controlled which also effect for efficient heat production. This study was conducted under different conditions of temperature, airflow, combustion time, and bulk density of rice husk in the combustion process using an experimental prototype hybrid rice husk burner with a fluidized bed. The availability of crystalline silica in rice husk charcoal and the CO and O2 compositions in the exhaust gas were analyzed using XRD analysis and gas analysis, respectively. Furthermore, elemental and thermogravimetric analyses were conducted to find the most efficient combustion parameter for the optimum conditions of rice husk combustion using the experimental rice husk burner. Therefore, the most efficient heat generation was achieved with the observation of the lowest CO emission, the nonavailability of crystalline silica in rice husk charcoal, at a low temperature and air flow rate (430 °C; 0.8 ms−1), high bulk density (175 kgm−3 and 225 kgm−3) and short combustion time (30 s).

Investigation on Alccofine’s Impact on The Strength and Durability Characteristics of Concrete

Supplemental cementitious material made from rice husk combustion is Alccofine. The influence on the strength and durability qualities is experimented in this research. Six different concrete mixes with differing concentrations of Alccofine and cement were prepared for the investigation. The concrete’s durability was further evaluated by absorption and quick permeability testing. The influence of Alccofine, a supplemental cementitious material, on the strength and durability qualities of concrete is investigated in this research. A series of laboratory studies were conducted in which varying quantities of Alccofine were added into the concrete mix. According to the results of the study, using Alccofine as substitute may greatly better the strength. The addition of Alccofine enhanced the compressive strength, with the greatest strength reached at a replacement level of 15%. Furthermore, it reduced the porosity, resulting in increased durability features such as resistance to water and chloride ion penetration. The research also discovered that adding Alccofine resulted in denser microstructure, which contributed to its increased mechanical qualities and durability. Finally, the study results indicate that using a supplemental material has the potential to increase its strength and durability.

Rice husk ash utilization, composition and properties: A brief review

Asian countries rely massively on rice to feed and sustain its massive population. For long the staple food has provided nourishment to the masses and the classes. Rice is grown in large quantities in Asian countries. A by-product of its cultivation is its husk. The husk of the rice grain is mainly utilized as a fuel for the boilers in the rice mills. The uncontrolled burnt rice husk referred to as rice husk ash consists majorly of silica. silica is used in a wide variety of commercial and industrial applications. Use of rice husk ash in various products serves to reduce the pollution caused by its pileup in localities especially close to the rice mills. More sustainable and an affordable source of Si would benefit the society rather than disposing rice husk ash in the fields and landfills. This brief review provides insights into the synthesis, applications, and properties of rice husk ash incorporated products either directly in the as received conditions or under modified conditions.

Behavior of NPK in carnation (Dianthus caryophyllus L.) cv. Delphi growing on a soilless crop system with recycling of drainage

In the soilless system crop of Colombian floriculture, the carnation cut flower is one of the most representative. The aim of this study was to determine the content of N, P, and K in the substrates based on burned rice husk (BRH) and coconut fiber (CF), in leachates, and in the tissue of the whole carnation plant, with three percentages of recycling. The study was carried out under greenhouse conditions, with standard carnation cv. Delphi planted at a density of 24.3 plants/m2, fertigated through a computerized system and an automatic drainage recycling system. A randomized complete block experimental design in a split-plot with nine treatments and three replications was used. The concentration of nitrate in the leachate was influenced by recycling levels, and that of the ammonium ion by the substrate with the highest BRH content; the percentage of N in the substrate decreased significantly with the increase in the BRH content. Phosphate content in the leachate was significantly higher in the treatment with 100% recycling and with the increase in the percentage of CF in the substrate; in the substrate, the P content also increased as a function of the increase in the percentage of CF. The concentration of the K in the leachate was significantly higher in the treatments without recycling and with a higher percentage of BRH; a significantly higher content of K is highlighted in the substrates with higher CF content.

Performance of SCC Concrete with Additional Materials of Rice Husk Ash

Concrete with high ductility, workable, high strength, easy to flow without compaction, and durable is a concrete need in the future. Concrete with this quality, one of which is to make self-compacting concrete (SCC). This paper reports performance of self compacting concrete (SCC) containing rice hush ash. Rice husk ash is waste from burning rice husks. The purpose of this study was to determine the performance of SCC concrete with the addition of rice husk ash. SCC specimens were made using rice husk ash (RHA) and SCC without rice husk ash (NRHA). The specimens were made with water cement ratio 0.30. Superplastisizer used is a type Naptha 511P. The result indicated that the workability of SCC containing rice hush ash (RHA) more workable compare SCC without rice hush ash (NRHA). The initial setting time of SCC with rice hush ash more slowly compare SCC without rice hush ash. The compressive strength, flexural strength, and tensile strength of SCC RHA mor higher compare SCC without RHA (NRHA). The tensile strength value of RHA and without RHA concrete meets the tensile strength requirements of RSNI T-12-2004.

Teknologi Pirolisis Pembuatan Asap Cair dari Sekam Padi

The production and use of liquid smoke from rice husks among the farming community in Belitang sub-district is still very limited and not many people even know about liquid smoke and its benefits. During the rice husk is made of charcoal and used for mixing the soil as an additional nutrient to the soil. Seeing these conditions, the aim of carrying out community service activities is to increase public knowledge of the potential of rice husk in the form of liquid smoke which can be used as an organic pesticide. The activity method is carried out in several steps, namely socialization, the process of making and assembling tools and the practice of making smoke by the community on a small scale. Designed pyrolysator equipment portable consisting of combustion chamber tubes, smoke cooling chamber tubes and smoke flow pipes which are used to produce liquid smoke. The rice husk burning process was carried out using a pyrolysis scheme within 6 hours and produced 90 ml of black liquid smoke with little oil content. This indicates that the liquid smoke produced is of low quality. The result of this Community Service Program (PPM) activity is that the community understands and understands the use of liquid smoke and the process of making liquid smoke.

MGIDI: a powerful tool to analyze plant multivariate data

BackgroundCommonly, several traits are assessed in agronomic experiments to better understand the factors under study. However, it is also common to see that even when several traits are available, researchers opt to follow the easiest way by applying univariate analyses and post-hoc tests for mean comparison for each trait, which arouses the hypothesis that the benefits of a multi-trait framework analysis may have not been fully exploited in this area.ResultsIn this paper, we extended the theoretical foundations of the multi-trait genotype-ideotype distance index (MGIDI) to analyze multivariate data either in simple experiments (e.g., one-way layout with few treatments and traits) or complex experiments (e.g., with a factorial treatment structure). We proposed an optional weighting process that makes the ranking of treatments that stands out in traits with higher weights more likely. Its application is illustrated using (1) simulated data and (2) real data from a strawberry experiment that aims to select better factor combinations (namely, cultivar, transplant origin, and substrate mixture) based on the desired performance of 22 phenological, productive, physiological, and qualitative traits. Our results show that most of the strawberry traits are influenced by the cultivar, transplant origin, cultivation substrates, as well as by the interaction between cultivar and transplant origin. The MGIDI ranked the Albion cultivar originated from Imported transplants and the Camarosa cultivar originated from National transplants as the better factor combinations. The substrates with burned rice husk as the main component (70%) showed satisfactory physical proprieties, providing higher water use efficiency. The strengths and weakness view provided by the MGIDI revealed that looking for an ideal treatment should direct the efforts on increasing fruit production of Albion transplants from Imported origin. On the other hand, this treatment has strengths related to productive precocity, total soluble solids, and flesh firmness.ConclusionsOverall, this study opens the door to the use of MGIDI beyond the plant breeding context, providing a unique, practical, robust, and easy-to-handle multi-trait-based framework to analyze multivariate data. There is an exciting possibility for this to open up new avenues of research, mainly because using the MGIDI in future studies will dramatically reduce the number of tables/figures needed, serving as a powerful tool to guide researchers toward better treatment recommendations.

Efficient extraction of silica from openly burned rice husk ash as adsorbent for dye removal

Rice is the staple food in many countries including Bangladesh. In Bangladesh, >80% of the total irrigated area is planted with rice, which generates a huge amount of rice husk (RH) as a solid waste which requires proper management. This study, therefore, aimed to extract amorphous silica from openly burned rice husk ash (RHA) using a simple method by avoiding calcination or combustion processes. The extracted silica was then applied for the removal of environmental contaminants i.e., methylene blue dye from an aqueous solution. It was found that the yield of silica produced from sulfuric acid-pretreated RHA was 72.4%. The FTIR absorption peaks at 1057 and 783 cm−1 indicate the presence of a highly condensed silica-containing asymmetric and symmetric siloxane (Si–O–Si) network mixture. The broad maximum bond peak intensity at 2θ = 22° by x-ray diffraction analysis also indicates that the produced silica was amorphous with a mesoporous structure. The surface area of sulfuric acid treated RHA-based silica was 183 m2/g. This silica resulted in a maximum adsorption capacity of 107 mg/g of methylene blue at pH 8 with a faster equilibrium reached at 60 min. The mechanistic study indicated that both Langmuir and Freundlich adsorption isotherms were both fitted well which suggested homogeneous adsorbent surfaces involving monolayer and multilayer adsorption processes.