Groundnut plant ash: Characterisation and adsorption efficacy study for removal of paraquat dichloride

35-42For the first time combustion residue of agricultural waste i.e. groundnut plant is characterized in detail and explored as an adsorbent for removal of chlorinated herbicide, paraquat. The study investigates the chemical, physical, mineralogical, and morphological characteristics of GPA (Groundnut Plant Ash) adsorbent produced using groundnut plant. GPA has been characterized using the Fourier Transform Infrared (FTIR) spectroscopy to determine the functional groups, and Scanning Electron Microscopy (SEM) to examine the surface morphology of the carbon. Batch adsorption is performed by varying adsorbent dosage, initial concentration and contact time. Result shows that the kinetic models mainly the pseudo-second order and Elovich model had the best fit. The equilibrium data are analyzed using different isotherm models. The adsorption capacity of GPA for paraquat removal is found 265.71 mg/m2  which is the highest reported value

Groundnut plant ash: Characterisation and adsorption efficacy study for removal of paraquat dichloride

For the first time combustion residue of agricultural waste i.e. groundnut plant is characterized in detail and explored as an adsorbent for removal of chlorinated herbicide, paraquat. The study investigates the chemical, physical, mineralogical, and morphological characteristics of GPA (Groundnut Plant Ash) adsorbent produced using groundnut plant. GPA has been characterized using the Fourier Transform Infrared (FTIR) spectroscopy to determine the functional groups, and Scanning Electron Microscopy (SEM) to examine the surface morphology of the carbon. Batch adsorption is performed by varying adsorbent dosage, initial concentration and contact time. Result shows that the kinetic models mainly the pseudo-second order and Elovich model had the best fit. The equilibrium data are analyzed using different isotherm models. The adsorption capacity of GPA for paraquat removal is found 265.71 mg/m2 which is the highest reported value

Rice Husk Ash for Fast Removal of 2,4-Dichlorophenoxyacetic Acid from Aqueous Solution

Rice husk ash (RHA) is a rich source of micronutrients and improves yield, and is spread on agriculture lands as a farming practice. For the first time, RHA has been evaluated as an adsorbent for pesticide removal from aqueous solutions. RHA was characterized extensively by X-ray fluorescence, Fourier transform infrared spectroscopy, BET surface area, CO 2 , H 2 O, N 2 and SO 2 (CHNS) analysis. 2,4-Dichlorophenoxyacetic acid (2,4-D), a commonly used pesticide, was chosen as a representative adsorbate for studying the effects of various parameters in batch adsorption. Compared with granulated activated carbon, RHA gave 10,000 times higher rate constant. Thus, RHA adsorbs 2,4-D instantly and stops its further transport through soil. On the basis of adsorption capacity, RHA dosage per hectare of land is recommended for different crops and fruits. Thus, RHA serves dual purposes: (a) as a source of micronutrients and (b) as an effective adsorbent for fast removal of pesticide, in addition to inhibiting groundwater leaching

Adsorptive removal of 2,4-dichlorophenoxyacetic acid from aqueous solution using bagasse fly ash as adsorbent in batch and packed-bed techniques

Among the several synthetic herbicides available currently, 2,4-D is a commonly used herbicide to control broadleaf weeds in agriculture and forestry. However, its increasing use in agricultural and nonagricultural activities has resulted in increasing concentrations of 2,4-D being detected in water bodies. Thus, there is a need to identify methods to remove 2,4-D to protect the environment. Among the various methods used for 2,4-D removal, adsorption is found to be effective, and several adsorbents have been studied to remove 2,4-D from aqueous solutions. In this study, we used bagasse fly ash (BFA), a common industrial waste generated in large amount worldwide, for 2,4-D removal from aqueous solution using batch and continuous packed-bed adsorption. In the batch adsorption process, the effects of initial concentration, contact time, temperature, pH, and particle size of BFA were studied. The packed-bed performance of BFA was investigated by varying the influent concentration (50–150 mg/L), flow rate (1.2–4 mL/min), and bed height (4.5–9 cm). Isotherm and thermodynamic parameters are determined for batch adsorption, whereas the performance of continuous adsorption is evaluated by different packed-bed models. The particle-size effect indicated the higher removal of 2,4-D on the bigger particles of BFA due to greater BET surface area and carbon-to-silica ratio than smaller particles. The maximum percentage removal (37.04) is achieved for an influent concentration of 50 mg/L, flow rate of 1.2 mL/min, and bed height of 6.5 cm. For the first time ever, the deactivation kinetic model was applied for the solid–liquid adsorption system and it showed the best fit among the selected models. The bed capacity (m²/g) of BFA is three times greater than synthetic activated carbon for adsorption of 2,4-D. This informs that the BFA can be used as an adsorbent for 2,4-D removal from aqueous solution

Adsorptive removal of diuron on biomass ashes: a comparative study using rice husk ash and bagasse fly ash as adsorbents

This study describes the use of two types of biomass ashes (BMAs) as adsorbents for diuron removal. Two BMAs, namely rice husk ash (RHA) and bagasse fly ash (BFA), were used in this study, and their adsorption behavior and adsorption mechanism were compared based on various characteristics, such as surface area, pore diameter, and volume. It was found that the particle size and the composition of these BMAs, especially the content of carbon and silica, primarily affect the adsorption kinetics and capacity. Compared with RHA, BFA has more carbon content (47.37%), and therefore shows higher adsorption capacity (43.48 μmol/g). In addition, BFA has larger external surface area and exhibited faster kinetics at the initial adsorption stage; by contrast, RHA due to its larger pore diameter allows for faster pore adsorption and surpasses the initial kinetic rate of BFA. For the same particle size (0.354–0.251 mm), the equilibrium capacity of BFA was found to be four times greater than that of RHA; in addition, the surface area of BFA is two times more than that of RHA, suggesting that BFA has more active sites than RHA. It was found that solution pH influences adsorption mechanism of diuron molecule on BMA. The uptake capacity of BFA and RHA is 10 times greater than natural adsorbents such as soil and is comparable with synthetic adsorbents such as activated carbon and multiwalled carbon nanotubes. To our knowledge, removal of diuron using ashes has not been reported previously