In the United States and in most of the world food dyes are exceedingly common. In addition to this, they have been brought into question as being dangerous for human and environmental health. From general observation and knowledge about this topic I knew that Red #40 dye (Allura Red AC) is at the height of this controversy. After some initial research, I discovered more information on Azo dyes, their effect on the environment, as well as wastewater treatment used to decontaminate water containing these dyes. This led to my interest on the topic of Electrochemical Advanced Oxidation Processes (EAOPs) as a fairly recent solution to environmental issues regarding contaminants in water. I was curious to see how these processes work, as well as
Background and Objective: the human activities generate a variety of contaminants. One of these contaminants is the pesticides which are used to exterminate the agricultural pest. Organophosphates are a class of pesticides which, were replaced with the organochlorines from a few decades ago, due to their less resistance. diazinon is one of Organophosphate insecticide which is classified as a relatively hazardous materials (Class II by the World Health Organization). Diazinon has many adverse effects such as disruption of the immune system (Immunotoxic), cytotoxicity and Genotoxicity. The insecticide is relatively soluble in water and the maximum remaining level in water is 1 mg/L. The release of diazinon into surface and groundwater resources is one of important worries. Several methods such as ultrasonic waves, biodegradation, optical degradation, ozonation, gamma rays, Fenton, UV / H2O2 and Photocatalytic degradation have been used to remove the diazinon. The complexity of the process, high cost and high consumption of chemicals are of the problems with these methods. Nano-photocatalytic methods are new developing methods to remove environmental pollutants. TiO2 has found more attention due to high photocatalytic activity, stability against the light corrosion, economic acceptability and lack of
A fuel cell is a device that produces an electrical current through a chemical reaction. All fuel cells contain a cathode and an anode, which are positive and negative electrodes, respectively. The chemical reactions which produce electricity occur at the electrodes. Fuel cells also contain an electrolyte, which carries electrically charged particles between the electrodes. A catalyst also aids to speed up the chemical reaction at the electrodes. In fuel cells, an impurity must serve as the electrolyte; if one uses distilled water for this experiment, it could serve only as the control, because purified water does not contain any substances that react at the electrodes. Some examples of impurities used as electrolytes in various types of fuel cells include
The technology behind hydrogen fuel cells is rather unremarkable, however, the difficulties and dangers created by the fuel cells will require extraordinary engineering. Today’s fuel cells use the same reverse electrolysis phenomena that Grove’s battery did over a century ago (Lampton). Hydrogen is ionized and passed through a membrane that separates the electrons from the hydrogen ions. The electrons are formed into an electrical current while the hydrogen ions react with the oxygen in the air to form water vapor, the heat generated by the reaction typically boils the water (Lampton). The catalyst and membrane can be tweaked and optimized by engineers to improve the technology but the basic principle will remain the same.
They are used extensively in the dye and printing industries, and 5-10% of the dyestuffs are lost in the industrial effluents (Sanroman et al., 2005). As for textile industries billions of littles of aqueous waste streams are generated every day. These effluents usually posses colour, high electrolyte concentration and a substantial amount of residual dyes that can produce environmental issues and problems. Colour is usually the first contaminant to be recognized in wastewater; a very small amount of dye in water (10-20 mg/l) is also highly visible and affects water transfarency and gas solubility of water bodies (Cameselle et al.,2005). These contaminated wastewater must first and foremost be treated before being released into the environment to avoid pollution and adverse impact. The treated wastewater must comply with the environmental regulatory standards set by the
Since the pre-historic era, natural dyes are common for their use in coloring of food substrate, leather, wool, silk and cotton. The use of this eco-friendly, non-toxic and non-allergic natural dyes have become important in order to avoid some hazardous synthetic dyes. However, given that the synthetic dyes are easier to use, cheap and widely produced and available, the usage of natural dyes continues on decreasing since the 19th century (Samanta, 2009).
For better results and increase the solubility, dispersion stability, levelling and fastness properties of the dyes additional dispersing agents added. These dispersing agents have a reducing effect on the dye during dyeing process and after dyeing they add to the COD and BOD of the efﬂuent. To overcome these types of environmental concerns, DyStar introduced a range of ‘Green’ disperse dyes under its econﬁdence program which have ecofriendly chemicals. The issues caused by the use of dispersing agents is being settled with the invention of disperse dyes having temporarily solubilizing groups. Another way of eliminating the use of dispersing agents during dyeing process, is dyeing with microencapsulated
The rapid growth of human population and industrialization has lead to the environmental pollution and the world is facing problems with a wide variety of pollution (Kshirsagar, 2013). The release of wastewater poses serious environmental challenges to the receiving water bodies (De-Bashan et al., 2002). Today, the demand for clean water is increasing worldwide and the main challenge of wastewater treatment is not only to produce clean water but it also support new developments (Velan and Saravanane, 2013). The process of bioremediation depends on the metabolic potential of microorganisms to detoxify or transform the pollutant, which is further dependent on accessibility and bioavailability (Bhatnagar and Kumari, 2013). Remediation can be enhanced by the addition of various microorganisms, called seeding or inoculation, to a polluted environment to promote increased rate of biodegradation (Antizar-Ladislao et al., 2008).
The effect of algal biomass on the rate of decolourization is shown in Fig. 8. The algal biomass concentrations used were 0.2 O.D- 1.0 O.D. for an initial dye concentration of 90 ppm for 6 days. The results showed that as the concentration of the algal biomass was increased, there was increase in the percent removal of dye from 88% to 100%. This may be due to an increase in the surface area of the biosorbent, which in turn increases the binding site (Ahmed El Nemr et al. 2005).
Main role of an Anion ion membrane is to conduct hydroxyl ions at very high rates from the cathode to the anode where reduction and oxidation of O2 and H2 occur. The AEM and its integration with the electrodes form the heart of the alkaline fuel cell. If the transport through the AEM is not sufficiently high and highly selective, the corresponding fuel cell will not find any practical application.
Wastewater is a broad term used to characterize the water with poor quality that have high quantity of pollutants and microorganisms.Water pollution is becoming a sever hazrd to survival of humanities. Industrial wastewater is greatly polluted that have very high amount of COD and inorganic nutrients. Untested dischager and insufficent treatment may direct to remarkable aquatic loss and consequent damage to the complete ecosystem.The textile industry is one of the rapidly developing industries and the number one polluter of clean water. It uses huge amount of water and generate high volumes of wastewater from various steps in the dyeing and finishing procedure. In excess to 80,000 tons of dyes utlize
Recently, Natural organic dyes like indigo and indigo carmine are widely imported extensively in many industrial issues like textiles, printing, dying, and food . Indigos Family are characterized by their high stability that arises from inter/intramolecular hydrogen bonding. The electronic and vibronic spectra of indigos are strongly influenced by π-domains intermo-lecular interactions . Also, Indigos are well known of their high photochromicty which enrich their potential applications in photonic, storage, and spintronic devices . Indigo carmine (IC), or 5,5′-indigodisulfonic acid sodium salt, is an organic salt derived from indigo by sulfonation, which renders the compound soluble in water. It is approved for use as a food colorant in the U.S and E.U. It has the E number E132. Indigo carmine is primarily employed as a pH indicator. It is blue at pH 11.4 and yellow at 13.0. Also, it is a redox indicator [4-6]. Indigo Carmine (IC) has a chemical formula of C16H8N2Na2O8S2, Molar mass (466.36 g/mol), and melting point (>300 °C). Moreover, Its other uses include indicating dissolved ozone through the conversion to isatin-5-sulfonic acid  and detecting superoxide, an important distinction in cell physiology  and being used as a dye in the manufacturing of capsules, and in obstetrics. Besides, the indigo carmine-based dye is used to detect
The decolorization potential of microorganism was assessed by examining its ability to degrade various textile dyes. All 10 dyes monitored showed decolorization as follows: Reactive Yellow 84 (complete decolorization in 5 h), Reactive Green 19A (95% in 24 h) , Reactive Red 120 (complete decolorization in 6 h), Reactive Blue 160 (complete decolorization in 3 h), Reactive Red 31(complete decolorization in 6 h), Solvent Red 24 (complete decolorization in 8 h), Basic Green 4 (80% in 24 h), Diamond Green 4 (complete decolorization in 24 h), Pigment Orange 31 (complete decolorization in 3 h) and RO16 (complete decolorization in 2 h), while in sterile, cell free medium decolorization did not occur up to 48 h of incubation suggesting the absence of abiotic decolorization. As RO16 showed complete decolorization in 2 h, this industrially important toxic azo dye was taken for further studies. Lysinibacillus sp. RGS could decolorize RO16 rapidly and thus was found to be better than the bacterial consortium DAS reported by Jadhav et al (2011). To confirm the decolorization, UV-Vis spectroscopic analysis was carried out. The absorption spectra of RO16 before and after treatment by Lysinibacillus sp. RGS in visible range were taken. Peak responsible for absorption maxima of parent dye (495 nm) were completely disappeared in the sample obtained after decolorization (Fig.S1) confirming the complete removal.
This has given rise to microbial electrosynthesis where chemolithoautotrophs are used to generate chemicals and biofuels are generated from electron donors. Non-carbon electron donors include H2, Fe2+, NH4 and all are produced and mobilized by electrical energy.
Pollution has been a wide problem in all over a world. In most of the industries used dyes as a coloring agent such astextile (Y.C. Wong et al., 2013), paint (King et al., 2008), leather (Sugashini S. et al., 2012), cosmetic (Suantakkamsonlian et al., 2011),paper, printing, cloth (George Z. Kyzas) andfood industries. The wastewaters discharged from dying industries which contains high biological oxygen demand (BOD),