Preparation, characterization and evaluation of adsorptive properties of orange peel based activated carbon via microwave induced K2CO3 activation

doi:10.1016/j.biortech.2011.10.005

Bioresource Technology

Volume 104, January 2012, Pages 679-686

https://doi.org/10.1016/j.biortech.2011.10.005 Get rights and content

Abstract

This work explores the feasibility of orange peel, a citrus processing biomass as an alternative precursor for preparation of activated carbon (OPAC) via microwave assisted K₂CO₃ activation. The operational parameters, chemical impregnation ratio, microwave power and irradiation time on the carbon yield and adsorption capability were investigated. The virgin characteristics of OPAC were examined by pore structural analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, nitrogen adsorption isotherm, elemental analysis, surface acidity/basicity and zeta potential measurement. The optimum conditions resulted in OPAC with a monolayer adsorption capacity of 382.75 mg/g for methylene blue and carbon yield of 80.99%. The BET surface area, Langmuir surface area and total pore volume were identified to be 1104.45 m²/g, 1661.04 m²/g and 0.615 m³/g, respectively. Equilibrium data were simulated using the Langmuir, Freundlich, Dubinin–Radushkevich, Redlich–Peterson, and Toth isotherms, and kinetic data were fitted to the pseudo-first-order, pseudo-second-order and Elovich kinetic models.

Graphical abstract

Highlights

► Highlight the renewable use of orange peel. ► Evaluate the effects of impregnation ratio, microwave power and radiation time. ► Short activation time of 6 min and low chemical impregnation ratio of 1.25. ► High BET and Langmuir surface area of 1104 and 1661 m²/g. ► Monolayer adsorption capacity of 382.75 mg/g and carbon yield of 80.99%.

Introduction

Orange, specifically known as Citrus sinensis, is one of the most favored subtropical fruits in the world. The fruit is globose, subglobose and oblate, with a width from 6.5 to 9.5 cm. The outer epicarp is orange when ripe, while the inner mesocarp is white, spongy and non-aromatic (Morton, 1987). Orange fruit is primarily eaten fresh and available as food complements in desserts, salads, gelatins, fruit cocktail, jam or juice combinations in the citrus processing industries (Armando et al., 2001). According to the Food and Agriculture Organization (FAO), the annual production of orange fruit in 2010 is projected at 64 million MT, translating to approximately 32 million MT of peels as the byproducts (Spreen, 2010).

Traditionally, orange peels (OPs) were processed to obtain the volatile and nonvolatile fractions of essential oils and flavoring in the carbonated drinks, ice creams, cakes, air-fresheners, perfumes and cosmetic products (Li et al., 2008). Besides, OPs have been reported to have germicidal, antioxidant and anti-carcinogenic properties as a remedy against breast and colon cancer, stomach upset, skin inflammation, muscle pain, and ringworm infections (Spreen, 2000). However, the application of these extracted constituents is limited due the overall demands for these value-added products are relatively insignificant. Therefore, it is necessary to find a rapid and easy route towards upgrading of the citrus processing biomass.

In this sense, the present work is aimed at evaluating the viability of microwave irradiation for preparation of activated carbon from OP via K₂CO₃ activation. The significant influences of microwave power, radiation time and chemical impregnation ratio on the carbon yield and adsorption capacity were investigated systematically. Structural, functional and surface chemistry of the prepared adsorbent was performed. Moreover, the adsorption equilibrium, isotherms, kinetics and thermodynamics were outlined.

Section snippets

Adsorbate

Methylene blue (MB), a monovalent cationic pollutant (Supplementary Fig. 1) difficult to be degraded in natural environment was selected as the model adsorbate in the present study. A stock solution of 500 mg/L was prepared by dissolving an appropriate quantity of MB in double distilled water and then diluted to the desired concentrations.

Preparation of activated carbon

Orange peel (OP), a by-product collected from the local restaurant, was the precursor used in the present study. The raw precursor was washed exhaustively with

Effect of chemical impregnation ratio

Effect of chemical impregnation ratio (IR) on the carbon yield and adsorption equilibrium of MB was evaluated at the microwave input power of 360 W and irradiation time of 5 min (Fig. 1a). It can be clearly observed that carbon yield increased from 72.45% to 85.14% with increasing IR from 0.25 to 1.25. Beyond the value, further increase in IR showed a gradually decrease of carbon yield. Similarly, augmenting IR from 0.25 to 1.25 illustrated an enhancement of adsorption uptake from 56.52 to 171.15

Conclusion

The results showed that orange peel is a potential raw precursor for preparation of high quality activated carbon. Integration of microwave heating has promoted porosity development in a short heating period. The optimum condition for preparation of OPAC has been identified at IR of 1.25, heating power of 600 W and irradiation time of 6 min. The adsorption behavior could be favorably described by Langmuir isotherm model, while the adsorption kinetic was well fitted to the pseudo-second-order

Acknowledgements

The authors acknowledge the financial support provided by Universiti Sains Malaysia under the Research University (RU) Scheme (Project No. 1001/PJKIMIA/814072) and RU-PRGS grant scheme (Project 465 No. 8043030).

References (33)

D. Adinata et al.
Preparation and characterization of activated carbon from palm shell by chemical activation with K₂CO₃
Bioresour. Technol.
(2007)
F.F. Avelar et al.
The use of piassava fibers (Attalea funifera) in the preparation of activated carbon
Bioresour. Technol.
(2010)
E. Demirbas et al.
Adsorption kinetics of a basic dye from aqueous solutions onto apricot stone activated carbon
Bioresour. Technol.
(2008)
H. Deng et al.
Preparation of activated carbons from cotton stalk by microwave assisted KOH and K₂CO₃ activation
Chem. Eng. J.
(2010)
A.H. El-Sheikh et al.
Bio-separation, speciation and determination of chromium in water using partially pyrolyzed olive pomace sorbent
Bioresour. Technol.
(2011)
M.E. Fernandez et al.
Effectiveness of Cupressus sempervirens cones as biosorbent for the removal of basic dyes from aqueous solutions in batch and dynamic modes
Bioresour. Technol.
(2010)
K.Y. Foo et al.
Insights into the modeling of adsorption isotherm systems
Chem. Eng. J.
(2010)
A.S. Franca et al.
Microwave assisted thermal treatment of defective coffee beans press cake for the production of adsorbents
Bioresour. Technol.
(2010)
P. Gao et al.
Preparation and characterization of activated carbon produced from rice straw by (NH₄)₂HPO₄ activation
Bioresour. Technol.
(2011)
Q. Li et al.
Equilibrium and a two-stage batch adsorber design for reactive or disperse dye removal to minimize adsorbent amount
Bioresour. Technol.
(2011)

Q.S. Liu et al.

Modification of bamboo-based activated carbon using microwave radiation and its effects on the adsorption of methylene blue

Appl. Surf. Sci.

(2010)

D.W. McKee

Mechanisms of the alkali metal catalyzed gasification of carbon

Fuel

(1983)

A.S. Mestre et al.

Activated carbons from sisal waste by chemical activation with K₂CO₃: kinetics of paracetamol and ibuprofen removal from aqueous solution

Bioresour. Technol.

(2011)

K. Nuithitikul et al.

Influences of pyrolysis condition and acid treatment on properties of durian peel-based activated carbon

Bioresour. Technol.

(2010)

A.A. Nunes et al.

Activated carbons from waste biomass: an alternative use for biodiesel production solid residues

Bioresour. Technol.

(2009)

K.B. Yang et al.

Preparation of high surface area activated carbon from coconut shells using microwave heating

Bioresour. Technol.

(2010)

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Preparation, characterization and evaluation of adsorptive properties of orange peel based activated carbon via microwave induced K2CO3 activation

Abstract

Graphical abstract

Highlights

Introduction

Section snippets

Adsorbate

Preparation of activated carbon

Effect of chemical impregnation ratio

Conclusion

Acknowledgements

Bioresour. Technol.

Bioresour. Technol.

Bioresour. Technol.

Chem. Eng. J.

Bioresour. Technol.

Bioresour. Technol.

Chem. Eng. J.

Bioresour. Technol.

Bioresour. Technol.

Bioresour. Technol.

Appl. Surf. Sci.

Fuel

Bioresour. Technol.

Bioresour. Technol.

Bioresour. Technol.

Bioresour. Technol.

Preparation, characterization and evaluation of adsorptive properties of orange peel based activated carbon via microwave induced K₂CO₃ activation