Removal of chromium (VI) from aqueous solutions using Diospyros discolor seed activated with nitric acid: isotherm and kinetic studies

2019 ◽  
Vol 79 (6) ◽  
pp. 1214-1221 ◽  
Author(s):  
Dian Arrisujaya ◽  
Nina Ariesta ◽  
Mamay Maslahat
Keyword(s):  
Nitric Acid ◽  
Aqueous Solutions ◽  
Kinetic Studies ◽  
Adsorption Efficiency ◽  
Batch Experiments ◽  
Adsorption Models ◽  
Chromium Vi ◽  
Optimum Ph ◽  
Scanning Electron ◽  
Analyze Data

Diospyros discolor seed activated with nitric acid was investigated for removing Cr(VI) from aqueous solutions. Batch experiments were used to determine the adsorption efficiency, effect of pH, adsorption isotherm, and kinetics. Langmuir and Freundlich adsorption models were used to analyze data of Cr(VI) uptake. Fourier transform infrared spectroscopy was used to investigate the functional groups and surface morphology was checked using a scanning electron microscope, coupled with energy dispersive spectroscopy. The optimum pH in Cr(VI) uptake was 3.5 and the maximum adsorption efficiency reached 100% at 60 min.

scholarly journals Synthesis, Characterization and Performance of Low-Cost Unconventional Adsorbents Derived from Waste Materials

2020 ◽  
Vol 10 (6) ◽  
pp. 7243-7256 ◽  
Keyword(s):  
Adsorption Mechanism ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Batch Experiments ◽  
Adsorbate Concentration ◽  
Optimum Ph ◽  
And Performance

Adsorption of the solute on solid is an equilibrium operation. The nature of adsorbent affects the efficiency of the operation. High surface area per unit volume is the essential attribute of a good adsorbent. Isotherm and kinetic studies are carried out to understand the adsorption mechanism. Many investigators have carried out batch experiments to study the effect of various parameters like initial adsorbate concentration, pH, particle size, and adsorbent dose. The use of adsorbents derived from low-cost materials makes this operation acceptable in industries. Regeneration of adsorbent can reduce the problem of disposal of used adsorbent material. Optimum values of affecting parameters can be determined from batch experiments. The isotherm and kinetic constants can be determined from batch experiments. These investigations give us an idea about the nature of adsorbent, maximum adsorption capacity, the order of adsorption, and optimum pH. This review sheds light on investigations on adsorbents derived from unconventional adsorbents and their characterization and performance evaluation.

scholarly journals Adsorption of hexavalent chromium ions from aqueous solutions using nano-chitin: kinetic, isotherms and thermodynamic studies

2021 ◽  
Vol 16 (2) ◽  
pp. 436-451
Author(s):  
Meghdad Sheikhi ◽  
Hassan Rezaei
Keyword(s):  
Aqueous Solutions ◽  
Correlation Coefficient ◽  
Hexavalent Chromium ◽  
Contact Time ◽  
New Technology ◽  
Kinetic Studies ◽  
Chromium Vi ◽  
Effects Of Ph ◽  
Pseudo Second Order ◽  
Adsorbent Dose

Abstract Treatment of the industrial wastewater before discharging into aquatic ecosystems using a new technology such as nanotechnology seems necessary. There are different methods for the removal of the heavy metals in the wastewater. In this study, nano-chitin was purchased from the Nano-Novin Polymer Company and used as an adsorbent for the removal of chromium (VI) ions from aqueous solution in a batch system. The effects of pH, temperature, contact time, concentration, and adsorbent dose were investigated. According to the results, the optimum conditions of adsorption occurred at pH = 6, temperature = 25 °C, 60 minutes contact time, and 0.6 g·L−1 adsorbent dose. Investigation of equilibrium isotherms showed that the isotherm fitted the Freundlich model with a correlation coefficient of R2 = 0.9689. The pseudo second-order model with the larger correlation coefficient had a greater fitness against experimental data in the kinetic studies. Thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy were calculated, which indicated spontaneous, endothermic, and random processes, respectively. Given the good results of this project, nano-chitin can be suggested as a novel adsorbent which is highly capable of adsorbing hexavalent chromium from aqueous solutions.

scholarly journals Exploring Adsorption Process of Lead (II) and Chromium (VI) Ions from Aqueous Solutions on Acid Activated Carbon Prepared from Juniperus procera Leaves

Processes ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 217 ◽  
Author(s):  
Ismat H. Ali ◽  
Mohammed K. Al Mesfer ◽  
Mohammad I. Khan ◽  
Mohd Danish ◽  
Majed M. Alghamdi
Keyword(s):  
Activated Carbon ◽  
Aqueous Solutions ◽  
Kinetic Studies ◽  
Ion Concentration ◽  
Isotherm Models ◽  
Solution Ph ◽  
Chromium Vi ◽  
Biosorption Process ◽  
Endothermic Process ◽  
Juniperus Procera

The adsorption potential of acid activated carbon prepared from leaves of Juniperus procera to remove Pb(II) and Cr(VI) toxic ions from aqueous solutions was investigated. The effects of solution pH, adsorbent mass, contact time, initial ion concentration and temperature on the biosorption process were studied, and the optimum conditions were determined. Moreover, Langmuir, Freundlich, Temkin and Dubinin–Radushkevich adsorption isotherm models were applied to analyze adsorption data. Thermodynamic parameters for the adsorption processes were calculated. Adsorption was found to be a spontaneous and endothermic process. In addition, kinetic studies revealed a pseudo-first order kinetics biosorption process. The obtained results suggest that acid activated Juniperus procera leaves powder can be used as a cheap, efficient and environmentally friendly adsorbent material with high removal efficiency up to 98% for Pb(II) and 96% for Cr(VI) at 0.80 and 1.00 g/100 mL, respectively. The duration of the process was 100 min and 120 min for Pb(II) and Cr(VI) ions, respectively. The morphology of the of prepared activated carbon was investigated by scanning electron microscope (SEM).

scholarly journals Sorption Studies of Chromium(VI) and Mercury(II) by High Temperature Activated Carbon from Syzygium Jambolanum Nut

2010 ◽  
Vol 7 (1) ◽  
pp. 299-307 ◽  
Author(s):  
S. Sophie Beulah ◽  
K. Muthukumaran
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
High Temperature ◽  
Kinetic Studies ◽  
Order Equation ◽  
Equilibration Time ◽  
Batch Experiments ◽  
First Order ◽  
Removal Process ◽  
Chromium Vi

High temperature activatedSyzygium Jambolanumnut carbon (HSJC) has been effectively used for the removal of Cr(VI) and Hg(II) from aqueous solution by batch experiments. Effect of pH, carbon dose and equilibration time were determined. Adsorption followed Freundlich and Langmuir isotherms. Kinetic studies indicated that the removal process followed reversible first order equation. Desorption of Cr(VI) was done with 1 M NaOH and 10% H2O2mixture and Hg(II) with 2% Na2S in 1% NaOH. The performance of HSJC was compared with a commercial activated carbon (CAC).

scholarly journals Sorption of chromium (VI) from electroplating rinse water by strong base anion exchanger: equilibrium and kinetic studies

2021 ◽  
Vol 1913 (1) ◽  
pp. 012076
Author(s):  
Prasanna S Koujalagi ◽  
Harish N Revankar ◽  
Raviraj M Kulkarni ◽  
Vijayendra R Gurjar
Keyword(s):  
Anion Exchanger ◽  
Kinetic Studies ◽  
Strong Base ◽  
Chromium Vi ◽  
Rinse Water

scholarly journals Enhancing removal efficiency of anionic dye (Cibacron blue) using waste potato peels powder

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kahina Bouhadjra ◽  
Wahiba Lemlikchi ◽  
Azedine Ferhati ◽  
Samuel Mignard
Keyword(s):  
Experimental Data ◽  
Contact Time ◽  
Potato Peel ◽  
X Ray ◽  
Cibacron Blue ◽  
Anionic Dye ◽  
Experimental Parameters ◽  
Optimum Ph ◽  
Potato Peels ◽  
Scanning Electron

AbstractIn the present study, the potato peel waste (PP) was used for the removal of the anionic dye Cibacron Blue P3R from an aqueous solution, activated with phosphoric acid (PPa) and calcined at 800 °C (PPc). The materials were characterized by Scanning Electron Microscope, Energy dispersive X-ray analysis and Fourier Transform Infrared Spectroscopy. The effects of various experimental parameters (pH, dye concentration, contact time) were also studied. The experimental results have shown that PPc has a greater capacity compared to pp and ppa. The capacity of PP bio-char (PPc) is 270.3 mg g−1 compared to PP (100 mg g−1) and PPa (125 mg g−1). Equilibrium experiments at 180 min for all materials were carried out at optimum pH (2.2): 76.41, 88.6 and 94% for PP, PPa and PPc respectively; and the Langmuir models agreed very well with experimental data. The ability of sorbent for the sorption of CB dye follows this order: calcined > activated > native materials. Potato peel biochar (PPc) can be considered a promising adsorbent for removing persistent dyes from water.

Sign in / Sign up

Export Citation Format

Share Document