Molecularly imprinted polymers (mips) as selective sorbents for wastewater pollutants

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1 Chapter 18 Molecularly imprinted polymers (mips) as selective sorbents for wastewater pollutants George Z. KYZAS and Nikolaos K. LAZARIDIS Aristotle University, Thessaloniki, Greece Introduction Apart from the conventional processes used in industry for the removal of pollutants from wastewaters (flotation, degradation etc.), an adsorption/binding recent process is used from researchers to selectively recognize and adsorb/bind target molecules (pollutants) from effluents. It is of great interest to prepare/design materials, which only selectively remove carcinogenic pollutants from wastewaters, as ions, dyes and other typical and potential target molecules. The ability to selectively recognize a target molecule in a vast pool of similar molecules is essential to biological and chemical processes. This process is called molecular recognition and it is an event that occurs everywhere in nature. It occurs when two molecules are both geometrically and chemically complementary; that is, when they can both fit together spatially as well as bind to each other using non-covalent forces, including hydrogen bonds, electrostatic interactions, hydrophobic interactions and weak metal coordination (Chen et al., 2002). Examples of this process include the binding of an enzyme to a substrate, a drug to a biological target (Britschgi et al., 2003), antigen/antibody recognition in the immune system (Sundberg and Mariuzza, 2002), and the formation of messenger RNA from DNA templates (Hofstadler and Griffey, 2001). The h molecular recognition is central to how biological systems work, especially at the cellular level. The observation of the various systems where processes of recognition occur (enzyme substrate complexes, antibody-antigen systems, DNA replication, membrane receptors, etc) has indicated a certain number of directions for the preparation of synthetic systems capable of molecular recognition. Molecular imprinting is not a new science. The earliest reports of imprinting go back to the early 1930s when a Soviet chemist M.V. Polyakov Sorption processes and pollution edited by Grégorio Crini and Pierre-Marie Badot Presses universitaires de Franche-Comté

2 Chapter 7 Decolorization of Dyeing Wastewater Using Polymeric Absorbents - An Overview George Z. Kyzas, Margaritis Kostoglou, Nikolaos K. Lazaridis and Dimitrios N. Bikiaris Additional information is available at the end of the chapter 1. Introduction The exact amount of dyes produced in the world is not known. Exact data on the quantity of dyes discharged in the environment are also not available. It is assumed that a loss of 1-2% in production and 1-10% loss in use (after being garment) are a fair estimate [1]. For reactive dyes, this figure can be about 10-20% due to low fixation. Due to large-scale production and extensive application, synthetic dyes can cause considerable environmental pollution and are serious health-risk factors. Although, the growing impact of environmental protection on industrial development promotes the development of eco-friendly technologies, reduced consumption of freshwater and lower output of wastewater [1], the release of important amounts of synthetic dyes to the environment causes public concern, legislation problems and is a serious challenge to environmental scientists. Globally, accessing to freshwater is becoming more acute every day. In the dyeing of textile materials, water is used firstly in the form of steam to heat the treatment baths, and secondly to enable the transfer of dyes to the fibers. Cotton, which is the world s most widely used fiber, is also the substrate that requires the most water in its processing [2]. The dyeing and rinsing of 1 kg of cotton with reactive dyes demands from 70 to 150 L water, 0.6 to 0.8 kg NaCl and anywhere from 30 to 60 g dyestuff. More than 80,000 tn of reactive dyes are produced and consumed each year, making it possible to estimate the total pollution caused by their use. After the dyeing is completed, the various treatment baths are drained out, including the first dye bath, which has a very high salt concentration, is heavily coloured and contains a substantial load of organic substances [2]. One solution to this problem consists in mixing together all the different aqueous effluents, then concentrating the pollution and reusing the water either as rinsing water or as processing water, depending on the treatment 2013 Kyzas et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

3 In: Dyeing: Processes, Techniques and Applications ISBN: Editor: Jie Fu 2014 Nova Science Publishers, Inc. Chapter 9 ADSORPTION AS THE MOST PROMISING DECOLORIZATION TECHNIQUE IN THE FINAL STEP OF TEXTILE EFFLUENTS TREATMENT George Z. Kyzas 1,2, 1 Department of Petroleum and Natural Gas Technology, Technological Educational Institute of Kavala, Kavala, Greece 2 Laboratory of General & Inorganic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Wastewater discharged from the dye houses can be one of the biggest contributors to aquatic pollution. The most studied dye classes, in the dye bearing effluent treatment, are reactive and basic. The dye loss from the dyeing process to the effluent is estimated 10 50% for reactive dyes and 0 5% for basic ones. Given that reactive and basic dyes could simultaneously exist in the equalization tank of a dye house, it is of fundamental importance to remove both of them. The dyeing process of cotton textiles using reactive dyes (cotton fibers makes up about half of the worldwide consumption of fibers) involves unit operations such as (i) desizing, (ii) scouring, (iii) bleaching, (iv) dyeing, and (v) finishing. The waste streams from each individual sub operation are collected to an equalization tank, where they are mixed and homogenized. So, the large volume of colorized effluents after the dyeing process has to be treated in some manner. A typical effluent treatment is broadly classified into preliminary, primary, secondary, and tertiary stages. The preliminary stage includes equalization and neutralization. The primary stage involves screening, sedimentation, flotation, and flocculation. The secondary stage reduces the organic load and facilitates the physical/chemical separation (biological oxidation). The tertiary stage is focused on decolorization, which is the main problem. In the latter, adsorption is characterized as a promising decolorization technique. Adsorption onto activated carbon is broadly used to limit the concentration of color in effluents. Adsorption has been applied either in a single mode, mainly for dyes removal from Corresponding author: St. Lucas University Campus, Technological Educational Institute of Kavala, Kavala 65404, Greece. georgekyzas@gmail.com; drkyzas@chem.auth.gr; kyzas@teikav.edu.gr. Complimentary Contributor Copy

4 In: Layered Double Hydroxides (LDHs) ISBN: Editor: Ian T. Sherman 2015 Nova Science Publishers, Inc. Chapter 6 LAYERED DOUBLE HYDROXIDES AND CERTAIN ENVIRONMENTAL APPLICATIONS (THE CONTRIBUTION OF LGICT) George Z. Kyzas 1,2 and Kostas A. Matis 2, 1 Department of Petroleum and Natural Gas Technology, Technological Educational Institute of Kavala, Kavala, Greece 2 Laboratory of General & Inorganic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Synthetic layered double hydroxides (LDHs) are hydrotalcite-like materials known for their ability to sorb anions from aqueous solutions, such as the chromates, arsenates, reactive azo dyes etc.; the latter will be merely used as remediation examples in the present. Their release into the environment is undesirable and their removal becomes environmentally important. The relative scientific area will be reviewed for the current developments in the literature. Synthesis and characterization aspects of the sorbents will be also commented. The influence of solution ph, conditioning duration, initial chromium concentration, sorbent concentration, sorbent particle size, and temperature was tested at sorption kinetic runs. Desorption experiments showed that the loaded material can be fully regenerated and reused. Thermodynamic analysis revealed that the sorption is spontaneous and endothermic. These materials usually exist in powder form, thereby exhibiting high surface area, especially their calcined compounds, and rapid kinetics for adsorption; but presenting often appreciable problem in the subsequent solid/liquid separation process. Keywords: Layered double hydroxides, dyes, arsenates, chromates, flotation Corresponding author address: University Campus (P.O. Box 116), Laboratory of General & Inorganic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. kamatis@chem.auth.gr.

5 11 Advanced Composite Adsorbents: Chitosan versus Graphene George Z. Kyzas* Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Department of Petroleum and Natural Gas Technology, Technological Educational Institute of Kavala, Kavala, Greece Abstract Two of the most promising, trendy but challenging adsorbent materials of the recent literature are chitosan and graphene. Numerous papers have been published reporting the synthesis of derivatives of them, presenting different properties from their origins. Chitosan is a nitrogenous polysaccharide and can be characterized as a very promising and cheap material, which can be produced in large quantities (poly-β-(1 4)-2-amino-2-deoxy-d-glucose). On the other hand, graphene and its oxide (graphene oxide) have been used as effective adsorbent toward environmental targets (pollutants). In this work, a direct comparison should be attempted regarding the major adsorption properties of chitosan- and graphene-based materials. Keywords: Chitosan, graphene, adsorption, comparison 11.1 Introduction Two of the most promising, trendy but challenging adsorbent materials of the recent literature is chitosan and graphene. Numerous papers have been published reporting the synthesis of derivatives of them presenting different properties from their origins. On the one hand, chitosan is a nitrogenous polysaccharide and can be characterized as a very promising and cheap material, which can be *Corresponding author: georgekyzas@gmail.com Ashutosh Tiwari and Lokman Uzun (eds.) Advanced Functional Materials, ( ) 2015 Scrivener Publishing LLC 463

6 In: Cellulose and Cellulose Derivatives ISBN: Editor: Md. Ibrahim H. Mondal 2015 Nova Science Publishers, Inc. Chapter 24 TREATMENT OF WASTEWATERS WITH MODIFIED CELLULOSE DERIVATIVES George Z. Kyzas and Nikolaos K. Lazaridis Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Cellulose is an organic compound with the formula (C 6 H 10 O 5 ) n, a polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1 4) linked D- glucose units. It can be characterized as naturally abudant, because it is one of the most iportnat important structural components of the primary cell wall of green plants, algae and oomycetes. Cellulose can be easily modified to other derivatives due to the numerous hydroxyl groups of its structure. Therefore, it can be used as adsorbent material. This study collects data from published works giving emphasis on the use of cellulose-based derivatives as adsorbent materials for the treatment of different-type wastewaters. One of the most serious environmental problems is the existence of hazardous and toxic pollutants in industrial effluents. Adsorption is considered to be one of the most promising techniques for wastewater treatment over the last decades. The economic crisis of the 2000s led researchers to turn their interest in adsorbent materials with lower cost. Based on the above, cellulose derivatives can be economically modified and alternatively used as adsorbents in order to remove various environemntal pollutants from wastewaters. This study can be divided in two major sections: (i) synthesis and characterization of cellulose derivatives, and (ii) adsorption evaluation of them for removing of different pollutants (dyes, cations, anions, etc). Keywords: cellulose, adsorption, pollutants, modification, derivatives Corresponding author: University Campus (P.O. Box 116), Laboratory of General & Inorganic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. georgekyzas@gmail.com. Corresponding author: University Campus (P.O. Box 116), Laboratory of General & Inorganic Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. nlazarid@chem.auth.gr.

7 In: Agricultural Wastes ISBN: Editor: Camille N. Foster 2015 Nova Science Publishers, Inc. Chapter 9 COFFEE WASTES AS ADSORBENTS George Z. Kyzas 1,2, 1 Department of Oenology and Beverage Technology, Technological Educational Institute of Kavala, Kavala, Greece 2 Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece One of the most recent trends in environmental technology is the research turn to green chemistry. It is general accepted that one of the most promising techniques for wastewaters treatment is adsorption. In this basis, numerous adsorbent materials have been synthesized up to now. However, there is a novel concept nowadays, which promotes the use of materials with the lowest possible cost. valuation of them for removing of different pollutants (dyes, cations, anions, etc). In the last years, the instant coffee industry has experienced a constant growth as instant coffee has become one of the most popular kinds of coffee drunk by millions of people around the world. As a consequence, large amounts of coffee grounds, which are the solid residues obtained during the processing of coffee powder with hot water or steam to prepare instant coffee, have been generated worldwide (in the order of 6 millions of tons per year). This work investigates the use of coffee wastes or coffee-based materials as adsorbents for the treatment of wastewaters. Keywords: coffee wastes, effluents, adsorption, pollutants Corresponding author address: University Campus (P.O. Box 116), Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. georgekyzas@gmail.com.

8 In: Citrus Fruits ISBN: Editor: Daphne Simmons 2016 Nova Science Publishers, Inc. Chapter 5 CITRUS RESIDUES AS SUPER-ADSORBENTS Ioannis Anastopoulos 1 and George Z. Kyzas 2,3, 1 Laboratory of Soils and Agricultural Chemistry, Department of Natural Resources and Agricultural Engineering, Agricultural University of Athens, Athens, Greece 2 Department of Oenology and Beverage Technology, Technological Educational Institute of Kavala, Kavala, Greece 3 Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece Water pollution is still a serious problem for the entire world. Adsorption technology is a promising process which based on fabrication of novel, cheap, non dangerous and highly sorptive materials for application in wastewater purification processes. Citrus species generally produced for the fresh consumption or the production of fruit juice but also have lot of application in medicine, food processing and agriculture sectors. This review collects information from published works about the alternative use of Citrus residues as efficient and promising adsorbents in clean water technology. For this purpose, isotherm (Langmuir, Freundlich, etc.), kinetic (pseudo-first, - second order, etc.), thermodynamic (free energy Gibbs, enthalpy, entropy) and desorption-regeneration studies were discussed in detailed. Moreover, significant factors such as ph, agitation time, temperature, adsorbent dosage and initial dye concentration are also reported extensively. Keywords: citrus peels, isotherms, kinetics, heavy metals, thermodynamics, modeling Corresponding author: George Z. Kyzas. University Campus (P.O. Box 116), Division of Chemical Technology, Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece. georgekyzas@gmail.com.