Low-cost Agricultural Waste Research Articles

Adsorption Isotherms studies of the removal of Indigo Blue dye from aqueous solution using chemically modified coconut shell

Introduction: The conversion and utilization of agricultural wastes in environmentally friendly processes have transformed these materials into useful rather than waste materials. Aim: This study investigates the adsorption of indigo blue dye from aqueous solution onto coconut shell, a low cost agricultural waste material in a batch process. Materials and Methods: Pulverized coconut shell was chemically modified and characterized using the Fourier Transform Infra Red spectroscopy and Scanning Electron Microscopy. Adsorption process using the chemically modified coconut shell was studied as a function of pH, initial dye concentration, adsorbent dose, and contact time. The adsorption equilibrium data were analyzed with Langmuir, Freundlich and Temkin isotherm models. Results: The results revealed that percentage of the indigo dye adsorbed from aqueous solution varied linearly with the adsorbent dose, concentration and time with maximum percentage dye adsorption of 88.4% at 70 mg dosage, 95.8% at 0.05 mg/L concentration and 90% at 1 hr contact time but varies non-linearly with pH with maximum percentage dye adsorption of 92.9% attained at pH of 5. The adsorption equilibrium data were analyzed with Langmuir, Freundlich and Temkin isotherm models with the Langmuir isotherm having the best fit to the adsorption process with R2 value of 0.998. The experimental data were best described by the pseudo-second order kinetics model. FTIR analyses reveal that the adsorption process was through a chemical interaction of the dye with some functional groups at the surface of the adsorbent Conclusion: The chemically modified coconut shell is an effective adsorbent for the removal of indigo dye from aqueous solution is by chemisorption process with the adsorbent surface energetically homogeneous (n < 1). Keywords: Adsorption, Indigo blue dye, Coconut Shell, Kinetics, Aqueous solution.

Study of pre-treatment of quinoline in aqueous solution using activated carbon made from low-cost agricultural waste (walnut shells) modified with ammonium persulfate.

Activated carbon made from agricultural waste (walnut shells) was investigated as a suitable adsorbent for effectively removing quinoline from industrial wastewater. The activated carbon was treated with phosphoric acid and oxidized by ammonium persulfate and its ability to adsorb pyridine and quinoline in aqueous solution was investigated. Kinetic parameters for the adsorption process were determined through pseudo-first-order and pseudo-second-order kinetic models and intraparticle diffusion models. Equilibrium experiments and adsorption isotherms were analyzed using Langmuir and Freundlich adsorption isotherms. After reaching equilibrium, the activated carbon adsorbed quinoline in preference to pyridine: the equilibrium adsorptions from individual aqueous solutions (200 μL L-1) of quinoline and pyridine were 166.907 mg g-1 and 72.165 mg g-1, respectively. Thermodynamic studies of quinoline adsorption were conducted at different temperatures and indicated that quinoline adsorption was an endothermic and spontaneous process. The column-adsorption of quinoline and pyridine was consistent with the Thomas model and the Yoon-Nelson model. The removal efficiency of quinoline reached more than 97% for a velocity of 6 mL min-1 at the initial adsorption stage.

Flexible, versatility and superhydrophobic biomass carbon aerogels derived from corn bracts for efficient oil/water separation

Resource utilization of corn bracts is essential from the viewpoint of environmental protection and sustainable development due to the adverse impacts emanating from potential fire hazards and environmental pollution of agricultural wastes. Herein, we present a versatile, convenient and green process to fabricate porous superhydrophobic biomass carbon (BC) aerogel by using corn bracts as main raw material, as well as its application in selective oil/water separation. During this process, the flexible and ultralight BC aerogel was obtained by corn bracts as main raw via simple alkalization, bleaching, freeze drying and carbonization. The resultant BC aerogels that constituted by interconnected corn bracts-based carbon fibers exhibit a three-dimensional hierarchical porous structure in microscale. The characterization results indicated that the obtained BC aerogels exhibit large specific surface areas (675.85 m2/g), mesoporous structures (3.92 nm on average), and superhydrophobicity (water contact angle > 150°). The BC aerogels can absorb a broad variety of oils and organic solvents with high selectivity and excellent absorption capacities (77.67–143.63 g/g). At the same time, the BC aerogels have excellent oil recoverability and reusability properties after ten recycles, making them particularly attractive materials to treat oily wastewater. The current research can offer a green approach to fabricate superhydrophobic BC aerogels with well-defined 3D network structure for efficient oil/water separation, and the fabrication of BC aerogels can be extended for the preparation of other functional aerogels by low-cost agricultural wastes for various applications.

Comparative analysis of removal of crude oil and some refined petroleum products from the environment using rice husk: Adsorption isotherm and kinetic studies

Rice husk a low cost agricultural waste was assessed for its efficiency as an oil spill sorbent by comparing its oil (crude oil, diesel and kerosine) uptake with that of a standard; conventional synthetic sorbent mat used in oil spill clean-up. The experiment was performed under the same experimental condition and procedure. The sorption process of crude oil, diesel and kerosine onto rice husk and the standard was studied using Langmuir, Freundlich, Elovich, Temkin and Dubinin – Radushkevich adsorption models while the sorption kinetics was studied using Lagergren pseudo-first-order, pseudo-second-order, intraparticle diffusion and liquid film diffusion models. Suitable environmental applicability of both sorbents was also studied.. The result of the study shows that rice husk sorbed 3.30g of crude oil, 2.50g of diesel and 1.95g of kerosine per unit mass while the standard sorbed 11.50g of crude oil, 10.34g of diesel and 8.20g of kerosine per uint mass. About 2.46g of crude oil, 1.60g of diesel and 1.57g of kerosine were recovered from a unit mass of rice husk, while, 9.67g of crude oil, 8.40g of diesel and 6.50g of kerosine were recovered from a unit mass of synthetic sorbent mat. The amount of oils retained by a unit mass of rice husk is about 0.84g of crude oil (25 % of absorbed crude oil), 0.90g of diesel (36 % of absorbed diesel), and 0.38g of kerosine (20 % of absorbed kerosine), while, 1.83g of crude oil (15 % of absorbed crude oil), 1.94g of diesel (19 % of absorbed diesel) and 1.70g of kerosine (20 % of absorbed kerosine) were retained by a unit mass of synthetic sorbent mat. The result of the study indicates that the standard is a better sorbent for oil removal than rice husk. Rice husk has the ability to retain sorbed oil which makes it a good sorbent when oil recovery is not required. The sorption process for both sorbents follows the Langmuir isotherm. intraparticle diffusion contributed more than liquid film diffusion in the sorption mechanism for the standard, while the reverse is the case for rice husk. The standard and rice husk can be applied on oil spill clean-up on land and surface waters. Rice husk is not a very efficient sorbent for oil spill mop.

Cashew apple juice as substrate for microbial fuel cell

Cashew apple juice which is an agro-based residue, more than 90% of the cashew apple is left as waste in the land after removing the cashew nuts. As a low cost agricultural waste, it is a potential source of substrate for industrial and biotechnological processes. It is reported that Cashew apple juice is used as a potential source of substrate for the production of bio ethanol, and other value added products such as dextran, lactic acid, mannitol and oligosaccharides etc. through fermentation. In this work, we report that the clarified cashew apple juice can be used as a potential substrate for microbial fuel cell generating open circuit voltage of 0.4 V and maximum power density and current density of 31.58 mW/m2, 350 mA/m2 respectively.

Orange tree leaves, a perfect adsorbent for the removal of Cd (II), Co (II), Zn (II) from wastewater

The present study explores the uptake capacity of low-cost agricultural waste for the removal of heavy metals, Co2+, Cd2+ and Zn2+, from aqueous solution. Studies conformed to Freundlich, Langmuir and Temkin adsorption isotherms. The values of constants for the thermodynamic and kinetic isotherms were found. The kinetic isotherm experiment data could be well described with the pseudo-second order kinetic model and thermodynamic studies indicated that the adsorption processes were spontaneous and endothermic with orange tree leaves under natural conditions. Experiments showed that Cd2+, Co2+ and Zn2+ adsorption increased with increasing pH and decreased with increasing the temperature and concentration of solutions. This study indicates that the developed method based on orange tree leaves is very simple, low-cost, fast and trusty for the removal of heavy metal ions from water and wastewater samples.

Optimization of Invertase from Aspergillus niger Grown on Low Cost Agricultural Wastes by Response Surface Methodology (RSM)

Optimization of Invertase from Aspergillus niger Grown on Low Cost Agricultural Wastes by Response Surface Methodology (RSM)

Efficient Removal of Cationic Dyes From Aqueous Solutions Using the Low-Cost Algerian Olive Cake Waste Adsorbent

The objective of our study was to evaluate the operating conditions for the removal of two dyes used in the textile industry, namely methylene blue (MB) and yellow basic 28 (BY28), from aqueous solutions. To do this, the low-cost agricultural Algerian olive cake waste (AAOCW) was used as an adsorbent. Equilibrium and kinetics tests were performed to define the applicability of this new adsorbent for the removal of selected dyes. The adsorption of the dyes on the AAOCW depends on the nature of the dye, the contact time, the pH, the initial concentration, and the amount of adsorbent. Two kinetic models including pseudo-first order and pseudo-second order were used to analyze the kinetic experimental data. The pseudo-second-order model provides the best results, suggesting that the chemisorption of dyes on the surface of the adsorbent plays an important role in the overall kinetics of the process. Finally, the characterization of the experimental isothermal data of MB and BY28 adsorption on AAOCW was performed using the Langmuir and Freundlich isotherms. Good fit results were obtained. The maximum adsorption capacity in monolayer was 25.98 mg g−1 and 38.95 mg g−1 for MB and BY28, respectively. The proposed adsorbent is a suitable candidate for removing dyes from aqueous media.

Computational study of acid blue 80 dye adsorption on low cost agricultural Algerian olive cake waste: Statistical mechanics and molecular dynamic simulations

The present study is focused on the adsorption of acid blue 80 dye on a low-cost sorbent, i.e. agricultural Algerian olive cake waste. FTIR analysis of the sorbent shows that the main compositional fractions are cellulose (cellobiose), hemicelluloses (xylose) and lignin. Batch isotherm studies are carried out under different experimental conditions in terms of temperature and pH. A subsequent FTIR spectrum analysis of the spent sorbent is adopted for a phenomenological interpretation of adsorption. Experimental adsorption isotherms show the presence of two steps, depending on the dye concentration. Adsorption isotherms are interpreted by statistical physics as well by molecular dynamics simulations. Based on statistical physics approach, a heterogeneous Bimodal-Gauss monolayer model is developed to evaluate the adsorption energy distribution and the isosteric heat of adsorption (Qst). The evaluations of adsorption energy distribution and Qst show that the interactions between adsorbent and adsorbate have greater magnitude than the adsorbate-adsorbate ones and aggregates of dye molecules are formed during the adsorption process. Furthermore, the heterogeneity of adsorbent is evaluated according the modeling approach showing that the temperature catalyzes the heterogeneity of surface and then different kinds of interaction occur during adsorption process. These interactions were identified by molecular simulations as Hydrogen, Van der Waals and electrostatic bonds. Finally, simulations results allow highlighting the lignin as the main compositional fraction of the sorbent responsible for adsorption of the investigated dye.

Basic red 2 and methyl violet adsorption by date pits: adsorbent characterization, optimization by RSM and CCD, equilibrium and kinetic studies.

The potential of raw date pits as a natural, widely available and low-cost agricultural waste has been studied in order to adsorb cationic dyes from an aqueous solution. Date pits were characterized by FTIR, SEM, BET, and XRD analysis. To optimize removal of two industrial dyes, basic red 2 (BR2) and methyl violet (MV), from aqueous solution using date pits, response surface methodology (RSM) is employed. Tests were carried out as per central composite design (CCD) with four input parameters namely contact time, temperature, initial concentration of adsorbate, and pH. Second-order polynomial model better fits experimental data for BR2 and MV and optimum values were then determined. In the optimum conditions, kinetic study was conducted and the pseudo-second-order model was found the best fitted model compared to pseudo-first-order model. Moreover, it was shown that intraparticle diffusion was not the sole controlling step and could be associated with other transfer resistance. On other hand, equilibrium isotherms were obtained for BR2 and MV and their maximum adsorption capacities were 92 and 136mgg-1 respectively. Two-parameter isotherm models like Langmuir, Temkin, Freundlich, Dubinin-Radushkevich, and Halsay were investigated to fit equilibrium data. Three error functions of residual root mean square error, chi-square statistic, and average relative error were used to comfort us in the selected models, which were actually Dubinin-Radushkevich and Langmuir for BR2 and Frendlich, Temkin, and Halsay for MV.

3-dimensional interconnected framework of N-doped porous carbon based on sugarcane bagasse for application in supercapacitors and lithium ion batteries

In this work, N-doped biomass derived porous carbon (NSBDC) has been prepared utilizing low-cost agricultural waste--sugarcane bagasse as the prototype, and needle-like PANI as the dopant. NSBDC possesses a special 3D interconnected framework structure, superior hierarchical pores and suitable heteroatom doping level, which benefits a large number of applications on ion storage and high-rate ion transfer. Typically, the NSBDC exhibits the high specific capacitance (298 F g−1 at 1 A g−1) and rate capability (58.7% capacitance retention at 20 A g−1), as well as the high cycle stability (5.5% loss over 5000 cycles) in three-electrode systems. A two-electrode asymmetric system has been fabricated employing NSBDC and the precursor of NSBDC (sugarcane bagasse derived carbon/PANI composite) as the negative and positive electrodes, respectively, and an energy density as high as 49.4 Wh kg−1 is verified in this asymmetric system. A NSBDC-based whole symmetric supercapacitors has also been assembled, and it can easily light a 1.5 V bulb due to its high energy density (27.7 Wh kg−1). In addition, for expanding the application areas of NSBDC, it is also applied to lithium ion battery, and a high reversible capacity of 1148 mAh g−1 at 0.1 A g−1 is confirmed. Even at 5 A g−1, NSBDC can still deliver a high reversible capacity of 357 mAh g−1 after 200 cycles, indicating its superior lithium storage capability.

Biosorption of metal ions on lignocellulosic materials: batch and continuous-flow process studies.

Metal adsorption capacities of bioadsorbents, derived from low-cost agricultural waste, were assessed. Batch and column experiments were conducted for evaluation of lead (Pb), cadmium (Cd), and chromium (Cr) sorption kinetics on to modified (by treating with base and acid) and unmodified sugarcane bagasse and corn cob. Langmuir, Freundlich, and Redlich-Peterson equations were used to understand metal adsorption behavior and Elovich and Lagergren's pseudo-first-order and pseudo-second-order kinetics equations were used for estimation of adsorption kinetics parameter. The suitability of the models to experimental data was reflected by high r2 values. Among sorption models, Langmuir and Redlich-Peterson were proved equally good and Cd, Cr, and Pb adsorption process followed the Langmuir isotherm. Batch adsorption experiment showed that the metal adsorption ability of the treated materials was higher than that of untreated. The adsorption sequence was Pb > Cr > Cd. Pseudo-second-order kinetics model was found suitable in describing the obtained data. Result of the column adsorption experiments supplement the batch results and revealed the role of agricultural waste materials in remediation of heavy metal-polluted water.

Comparative Studies of Invertase Enzyme from Low Cost Agricultural Waste Substrates By Saccharomyces CerevisiaeIsolated From Grape Juice

Comparative Studies of Invertase Enzyme from Low Cost Agricultural Waste Substrates By Saccharomyces CerevisiaeIsolated From Grape Juice

Adsorption of Phenol and Chlorophenol Mixtures on Silicalite-1 Determined by GC-MS Method

A method is presented in which gas chromatography coupled with mass spectrometry (GC-MS) allows quantitative simultaneous detection of mixtures of phenol (Ph), 2-chlorophenol (2-CPh), 3-cholorphenol (3-CPh), and 4-cholorophenol (4-CPh) in aqueous mixtures after being adsorbed on silicalita-1, utilizing selected-ion monitoring (SIM) and full-scan modes mass selective detection. GCMS with SIM at m/z = 64 and m/z = 128 showed good detection selectivity for mixtures of Ph, 2-CPh and 3-CPh (M1), and 2-CPh and 4-CPh (M2). Silicalita-1 was obtained from an amorphous organo-alumino-silicic gel from rice husk, an abundant and low cost agricultural waste residue that is readily available in large quantities. This product was used as a sorbent for solid phase extraction of organic analytes from aqueous solutions. The adsorption of the three chlorophenol isomers, ortho-, meta-, and para-, by silicalite-1 has been studied independently, showing that meta- and para-chlorophenol isomers are adsorbed more than ortho-chlorophenol. However the adsorption behavior of mixtures of these isomers was not reported. In this work, it was found that when the ortho-isomer is mixed either with meta or para-chlorophenol, considerable differences were observed in the adsorption process; in the studied mixture, the ortho-isomer was adsorbed more than the meta-and para-chlorophenol.

Mesoporous activated coconut shell-derived hydrochar prepared via hydrothermal carbonization-NaOH activation for methylene blue adsorption

Mesoporous activated carbon was prepared using a hydrochar derived from coconut shell waste through hydrothermal carbonization and NaOH chemical activation process (COSHTC). Three sets of activated carbons were obtained with different hydrochar:NaOH impregnation ratios (1:1, 1:2, and 1:3). Among these ratios, 1:3 (COSHTC3) exhibited the optimum adsorption for methylene blue (MB). COSHTC3 adsorbed MB with an initial concentration of 25–250 mg/L at pH 3–11 and 30 °C. The adsorption isotherm of MB on COSHTC3 demonstrated that Langmuir isotherm could be better applied at a maximum monolayer adsorption capacity of 200.01 mg/g at 30 °C. The data was well fitted to the pseudo-second-order (PSO) kinetic model. These results show that the COSHTC3 prepared from low-cost agricultural waste (coconut shell) with average pore diameter 28.6 Å and surface area 876.14 m2/g acts as a better adsorbent for removal of cationic dyes and could pave the way for more low-cost adsorbents for dye removal.

Enhanced adsorption of cationic dyes using sulfonic acid modified activated carbon

Activated carbon (MTLAC) and sulfonic acid modified activated carbon (MTLAC-SA) were prepared from a low cost agricultural waste material matured tea leaf (MTL). BET surface area of MTLAC and MTLAC-SA was found to be 1313.4m2/g and 1169.3m2/g respectively. Synthesized materials were applied for adsorption of both anionic and cationic dyes. Rhodamine B (RhB), methylene blue (MB), brilliant green (BG), crystal violet (CV) and orange G (OG) were taken as the model dye. After modification, the activated carbon showed enhanced adsorption capacity for adsorption of cationic dyes. The effect of various parameters such as pH, initial dye concentration, adsorbent dose, ionic strength on adsorption process was investigated. A slight increase in adsorption capacity was observed with increase in concentration of existing ion. The equilibrium adsorption data were best described by Langmuir model. The maximum adsorption capacity for RhB and OG using MTLAC-SA (MTLAC) was found to be 757.6 (398.4)mg/g and 105.7 (318.5)mg/g respectively. The adsorption kinetics was best fitted with pseudo second order kinetic model. The thermodynamic study illustrated that the adsorption process is endothermic and spontaneous in nature.

Utilization of acid pre-treated coconut dregs as a substrate for production of detergent compatible lipase by Bacillus stratosphericus

In recent years, many efforts have been directed to explore the methods to reduce the production costs of industrial lipase by improving the yield and the use of low-cost agricultural wastes. Coconut dregs, which is a lignocellulosic by-product from coconut oil and milk processing plants, is rich in cellulose (36%) and crude fat (9%). A newly isolated Bacillus stratosphericus has been demonstrated to perform cellulose hydrolysis on coconut dregs producing fermentable sugars. The highest extracellular lipase activity of 140 U/mL has been achieved in submerged fermentation with acid pre-treated coconut dregs. The lipase was found to be active over a wide range of temperatures and pHs. The activity of lipase can be generally increased by the presence of detergent ingredients such as Tween-80, cetyltrimethylammonium bromide, hydrogen peroxide and phosphate per sulphate. The great compatibility of lipase in commercial detergents has also underlined its potential as an additive ingredient in biodetergent formulations.

Adsorption Kinetic and Isotherm Studies of Azure-A on Various Activated Carbons Derived from Low Cost Agricultural Wastes

The present study narrates the eminent role of agricultural wastes as adsorbents viz., Sorghum Vulgare Carbon (SVC), Zea Mays Carbon (ZMC), Sorghum Vulgare Varity Carbon (SVVC), Ceiba Peutandra Carbon (CPC), Projobis Juliflora Carbon (PJC) for the removal of Azure-A (AA) dye from waste water. Experimental parameters such an effect of initialconcentration, contact time, dose, pH and particle size have been analyzed. The experimental results are there analyzed using Freundlich, Langmuir, Temkin, Redlich–Peterson and Dubinin–Radushkevich isotherm models. Multiple kinetic equations (first order, pseudo first order and pseudo second order) were applied to the adsorption kinetics of AA on various activated carbons. Surface morphology of the adsorbents before and after adsorption is studied by Scanning Electron Microscopy (SEM-Edax). FT-IR analyses revealed the presence of functional groups of dye on the adsorbents. It is inferred from the experimental result that the activated carbons (SVC, ZMC, SVVC, CPC and PJC) from agricultural wastes can be applied as an adsorbent in the removal of AA dye from waste water.

An experimental and quantum chemical study of removal of utmostly quantified heavy metals in wastewater using coconut husk: A novel approach to mechanism

The present study explores the uptake capacity of low cost agricultural waste i.e.Unmodified Coconut (Cocos nucifera L.) Husk for the removal of heavy metal (Pb2+, Cu2+, Ni2+ and Zn2+) ions from industrial wastewater. The effect of various operational parameters such as adsorbent dose, high initial metal concentration (100mg/L–500mg/L), pH, temperature and agitation time on the removal of these ions has been investigated using batch experiments. The results showed that maximum uptake through adsorption occurred at 443.0mg/g (88.6%) for Cu, for Ni with 404.5mg/g (80.9%), 362.2mg/g (72.4%) for Pb2+ and 338.0mg/g (67.6%) for Zn2+ ion simultaneously. The adsorption capacity was found to be sensitive to the amount of adsorbent, heavy metal ion concentration, pH, temperature and contact time. The experimental statistics have been correlated and interpreted by a new proposed mechanism based upon quantum chemical study of the adsorbent. The theoretical study using quantum has provided the rich electron donation sites of Coconut Husk and hence proposed mechanism of removal. The various adsorption isotherms (Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Flory-Huggins), SEM study and physico-chemical properties of the ions suit well to the observed data.

Methylene blue adsorption via maize silk powder: Kinetic, equilibrium, thermodynamic studies and residual error analysis

Abstract The potential of maize silk powder (MS) as a natural, widely available and low-cost agricultural waste in order to adsorb methylene blue (MB) from an aqueous solution has been studied. The adsorbent surface morphology has been studied using SEM and FTIR. The effect of operating conditions such as contact time, solution pH and initial MB concentration and the important frequently missed parameters such as salt effect (using NaCl and Na 2 HPO 4) , temperature effect (for ΔH°, ΔG° and ΔS°), solution pH and detailed error analysis have been determined. A rate study indicated the process followed pseudo-second order kinetics. The adsorption equilibrium was modeled for best fit using ten commonly-used isotherm models and the Jovanovic equation gave the best correlation of the experimental data.