Sana Sadaf

Removal of Indosol Turquoise FBL dye from aqueous solution by bagasse, a low cost agricultural waste: batch and column study

AbstractThis study involves the remediation of dye containing synthetic wastewater using bagasse, a low cost agricultural waste by batch and column methods. The simulated wastewater was prepared using Indosol Turquoise FBL, commonly used dye in the textile industry. Sugarcane bagasse was used in native, HCl-treated and Na-alginate-immobilized forms. The effect of different process parameters such as medium pH, biosorbent dose, contact time, initial dye concentration and temperature on the biosorption capacity of bagasse was investigated in batch study. Maximum dye removal (65.09 mg/g) was obtained with HCl-treated bagasse. Pseudo-second-order kinetic model was better fitted to the experimental data. The equilibrium data were best described by Langmuir adsorption isotherm model. The thermodynamic study indicated the thermodynamic nature of biosorption process. Effect of surfactants, heavy metal ions and salt concentration was also explored. Breakthrough capacities were also investigated in column mode stud...

Removal of Novacron Golden Yellow dye from aqueous solutions by low-cost agricultural waste: Batch and fixed bed study

The present work describes the removal of Novacron Golden Yellow (NGY) dye from aqueous solutions using peanut hulls. The experiments were performed with native, pretreated and immobilised forms of peanut hulls. The effect of various operational parameters (pH, biosorbent dose, initial dye concentration and temperature etc.) was explored during batch study. NGY showed maximum removal at low pH and low biosorbent dose. High initial dye concentration facilitated the biosorption process. Maximum dye removal with native, pretreated and immobilised biomass was found to be 35.7, 36.4 and 15.02 mg/g respectively. The experimental data were subjected to different kinetic and equilibrium models. The kinetic data confirmed the fitness of pseudo-second-order rate law for NGY biosorption. The equilibrium modelling was carried out by Freundlich, Langmuir and Temkin models. The isothermal data of NGY removal were best described by Freundlich adsorption isotherm. Negative values of Free energy change (Δ G0) for NGY with native and pretreated biomass depicted the spontaneous nature of biosorption process. In column mode, the effects of bed height, flow rate and initial dye concentrations were optimised. Maximum NGY biosorption (7.28 mg/g) was observed with high bed height, low flow rate and high initial concentration in continuous mode. Bohart–Adams model best fitted to the data obtained from column studies. The results indicated that the peanut hulls could be used effectively for the removal of dyes containing wastewater.

Uranium remediation using modified Vigna radiata waste biomass

Present study was designed to explore the possibility of Vigna radiata biomass for recovery of uranium ions. Various fundamental process parameters i.e., pH, contact time, temperature and initial uranium ions concentration were optimized and maximum uranium removal (230mg/g) was achieved at pH 4, biosorbent dose 0.05g, contact time 60min contact time and temperature 40°C using 400mg/L uranium ions concentration. The biomass was also pre-treated by different physical and chemical pretreatments to check out their effect on the adsorption capacity. Different kinetic and equilibrium models were applied to the experimental data to understand the uranium adsorption mechanism. Freundlich isotherm and pseudo-second order kinetic model explained well the adsorption of uranium ions onto Vigna radiata biomass. The biomass physical and chemical pretreatments significantly affected the uranium adsorption and CH3COOH 0.15M solution found out to be efficient for de-sorption. FT-IR analysis of native and loaded biomass confirmed the involvement of carbonyl and hydroxyl groups in the uranium adsorption process. The results outcome revealed that Vigna radiata biomass can be used for uranium adsorption in view of low cost and high adsorption efficiency.

Adsorptive removal of direct dyes by PEI-treated peanut husk biomass: Box–Behnken experimental design

This paper reports the application of Box-Behnken experimental design to illustrate the adsorption of direct dyes (Indosol Black NF and Indosol Orange RSN) using polyethyleneimine (PEI)-treated peanut husk biomass. The effect of three independent variables (initial dyes concentration, biosorbent dose and pH) was investigated during the study. Maximum biosorption capacity (141 and 98.2 mg/g) of PEI-pretreated biomass was achieved with 200 mg/L initial dye concentration and 0.05 g/50 mL biomass dose for Indosol Black NF and Indosol Orange RSN, respectively. Acidic pH was found to be favourable for maximum dyes removal. Characterisation of biosorbent was carried out through Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy, thermogravimetric analysis (TGA) and point of zero charge determination. FT-IR analyses confirmed the involvement of carboxylic and carbonyl groups. The desorption study was also conducted to check out the possibility of regeneration of dyes and adsorbent and it was found that 51.58 and 76.6% of Indosol Black NF and Indosol Orange RSN, respectively, can be desorbed from the loaded biosorbent by using 1 M NaOH solution. The results indicated that PEI-treated peanut husk biomass can be used as an efficient biosorbent for the removal of Indosol Black NF and Indosol Orange RSN dyes from aqueous solutions.

Adsorptive removal of Drimarine Red HF-3D dye from aqueous solution using low-cost agricultural waste: batch and column study

This study involves the utilisation of peanut husk for the removal of Drimarine Red HF-3D dye from aqueous solutions. Batch study experiments were conducted with native, HNO3-treated and Na-alginate-immobilised peanut husk biomass. Maximum dye removal (95.24 mg/g) was obtained with HNO3-treated biomass. The experimental data were successfully explained with a pseudo-second-order kinetic model for all types of biosorbents. The equilibrium data fitted well to the Freundlich adsorption isotherm model. A thermodynamic study was also carried out to check the nature of the adsorption process. A fixed-bed column study for Drimarine Red HF-3D was carried out to optimise the effect of bed height, flow rate and initial dye concentration using peanut husk biomass. The column study showed that biosorption capacity increased with the increase in initial dye concentration and bed height, but decreased with increased flow rate. Data for Drimarine Red HF-3D were in very good agreement with the bed depth service time model. Fourier transform infrared analysis demonstrated the involvement of different functional groups in dye biosorption. These results showed that peanut husk biomass possessed good potential for the removal of Drimarine Red HF-3D from aqueous solution.

Biosorption of Foron turquoise SBLN using mixed biomass of white rot fungi from synthetic effluents

In the present study, biosorption of Foron turquoise SBLN using mixed biomass of white rot fungi was investigated in batch mode. The effect of process parameters such as pH of solution, medium temperature, biosorbent concentration, dye initial concentration, contact time etc. was investigated for enhanced removal of the dye. Maximum dye removal was observed at pH 2, biosorbent dose, 0.1 g/100 ml and temperature 30°C. The equilibrium data were analyzed by commonly employed Langmuir and Freundlich isotherm equations. The results show that the equilibrium data were better described by Freundlich isotherm model as compared to Langmuir equation. The biosorption kinetic data were found to follow the pseudo-second-order model. The results therefore indicated that mixed biomass of whiterot fungi could be used as natural biosorbent to remove dyes from aqueous effluents.

Removal of COD from real textile effluents using agro-industrial wastes

AbstractIn this work, the biosorption potential of agro-industrial wastes was assessed for the removal of chemical oxygen demand (COD) from real textile effluents. The screening test conducted indicated that corncobs biomass has maximum potential among five agricultural waste materials (sugarcane bagasse, peanut husk, corncobs, cotton sticks, and sunflower) to remove COD from both textile effluents. The effect of important operating parameters like biosorbent dose, agitation time, agitation speed, and temperature was evaluated during the study. The maximum COD removal (80.8 and 72.4% for Effluents 1 and 2, respectively) was achieved at 0.5 g biosorbent dose and 140 rpm agitation speed. The biosorption process was found to be exothermic in nature. The data were also subjected to different kinetic and equilibrium models and the results depicted the fitness of pseudo-second-order kinetic model and Langmuir adsorption isotherm on the experimental data. The physicochemical characteristics (pH, electrical condu...

Equilibrium modeling for adsorptive removal of Indosol Black NF dye by low-cost agro-industrial waste: batch and continuous study

AbstractIn the present study, a low-cost agricultural waste, peanut husk, has been used as a potential biosorbent in native, pretreated and sodium-alginate immobilized form for the adsorptive removal of Indosol Black NF dye from aqueous solutions. Pretreatment of peanut husk with a chelating agent, polyethyleneimine, significantly enhanced its biosorption capacity. Different important process parameters like pH, contact time, biosorbent dose, initial dye concentration, and temperature were optimized during the study. The biosorption process was found to be feasible at acidic pH and was exothermic in nature. An agitation time of 15–30 min was sufficient to get equilibrium with native and pretreated biomass while immobilized biomass took 1 h for attainment of equilibrium. Maximum biosorption capacity (89.6 mg/g) was with pretreated biomass. Dye biosorption process followed pseudo-second-order kinetic model and equilibrium data fitted well to Langmuir isotherm model. Thermodynamic study indicated the spontan...