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Anaerobic Biotransformation of Reactive Textile Dyes
Published in Gregory D. Boardman, Hazardous and Industrial Wastes, 2022
M. Inan Beydilli, Spyros G. Pavlostathis, Wayne C. Tincher
The single most pressing environmental problem facing the textile industry is related to reactive dyes. The increased use of cotton has led to substantial growth in the usage of reactive dyes. As a result, the management of the spent reactive dyebaths has become a challenging and pressing problem. The textile industry is confronted with the problem of color removal and effluent salt content reduction. As regulations are becoming ever more stringent, the need for more technically and economically efficient means of both color and salt reduction from the plant effluent grows more acute. At the present time, there are no economically attractive means to achieve the reduction of these two parameters. Existing physical/chemical technologies for color removal are very expensive and commercially unattractive.
Dyeing and Recent Developments
Published in Asis Patnaik, Sweta Patnaik, Fibres to Smart Textiles, 2019
Prithwiraj Mal, Debojyoti Ganguly
These dyes are the youngest class of dyestuff for cellulosic material. Other classes of dyes are attached with the textile material either by ionic bond or physical attraction. Reactive dyes attach with the cellulosic material by covalent bond formation. The reactive dyes have a wide range of shades, good fastness properties, high brilliancy, easy application method and high reproducibility (Shore 1995; Shenai 2000). The structure of reactive dyes has a reactive group and a chromophore, which contains the colour. The reactive group of the dyes reacts and forms covalent bond with the fibre. During dyeing process, soda ash is required to maintain alkaline pH to fix the dyestuff with fibre. Reactive dyes are divided into two main categories, namely cold brand and hot brand. Cold brand reactive dyes are applied in cold temperature (45°C–50°C), whereas hot brand reactive dyes require high temperature (95°C–100°C) for dyeing. Reactive dyes can also be applied on wool, silk and nylon fibres. Although these dyes have very high fixation ratio, proper soaping and washing are required after dyeing to remove all unfixed and hydrolyzed dyes from the fibre surface. Perspiration fastness of reactive dyes is very poor.
Fabric Dyeing and Printing
Published in Tom Cassidy, Parikshit Goswami, Textile and Clothing Design Technology, 2017
The batches of light delicate and heavy structurally stable fabrics can be dyed in winches and jiggers, respectively. The general principle in exhaust dyeing of reactive dyes is to exhaust as much dye as possible onto the fiber using salt under neutral or very slightly acidic conditions. Under the conditions in which the dye does not react or react negligibly, leveling takes place. The pH of the bath is then raised by the addition of alkali and the reaction is allowed to undergo for a particular time at a particular temperature dictated by the reactive group present in the reactive dyes. Dyes having different reactive groups are advisable not to be mixed as the reaction conditions differ.
Insight into the adsorptive mechanisms of methyl violet and reactive orange from water—a short review
Published in Particulate Science and Technology, 2023
Azrul Nurfaiz Mohd Faizal, Nicky Rahmana Putra, Muhammad Abbas Ahmad Zaini
Reactive orange 16 (RO16), often known as Remazol brilliant orange 3R, is an anionic azo reactive dye that is made up of azo –N=N– (chromophore) along with hydroxyl (solubilizing), and amine and substituted amine (auxochrome) (Pal 2017). The sodium salt of sulfonic acid that solubilizes in water consists of chlorotriazine or vinyl sulfone reactive groups (Teli 2015). Reactive dye exhibits favorable characteristics of bright color and water-fastness (Ahmad and Rahman 2011). Like MV, RO16 is also applied in textile, paint, pharmaceutical, leather, printing, paper, and wood (Kim, Lee, and Cho 2015; Abdulhameed, Jawad, and Mohammad 2019). The azo compound renders RO16 to be biologically impenetrable (Fathi et al. 2020). Thus, it bears similar drawbacks to other synthetic dyes. Excessive contact with RO16 can result in skin and eyes irritation, allergy, asthma, genetic mutation, dermatitis, jaundice, and cancer (Naushad et al. 2016; Abdulhameed, Jawad, and Mohammad 2019; Tanhaei, Ayati, and Sillanpää 2019). In the aquatic ecosystem, the disruption of photosynthetic activity indirectly endows a toxic environment to organisms therein due to the presence of aromatic compounds (Abdulhameed, Jawad, and Mohammad 2019; Ma et al. 2019).
Preparation and characterization of ultrafiltration membranes from PPSU-PES polymer blend for dye removal
Published in Chemical Engineering Communications, 2021
Dalia Muthana Al-Ani, Faris H. Al-Ani, Qusay F. Alsalhy, Salah S. Ibrahim
Industrial wastewater treatment is one of the most important means of protecting the water environment from chemical and physical pollution. Most industrial wastewater contains various chemical compounds, which varies by industry. Dyes are utilized to a large extent in many industries, including plastic, rubber, paper, textile, and cosmetic industries. There are more than 10,000 commercial pigments and dyes available and more than 700,000 tons are manufactured every year worldwide (Garg et al. 2004). The dyes are commonly used to color cellulosic fibers (e.g.cotton). However, coloring with reactive dyes generally causes environmental problems (Jiraratananon et al. 2000). The strict environmental laws restrict the discharge of these effluents into rivers, streams, or any receiver without proper treatment. Many chemical and physical processes have been utilized for the decolorization and refinement of dyeing from wastewater, such as coagulation, adsorption, chemical degradation, and biodegradation (Al-Degs et al. 2008). Toxic and nonbiodegradable dyes discharged into stream water can lead to increasing pollutant concentrations and environmental risks. Moreover, under anaerobic conditions, dyes can degrade to more dangerous elements. As a result, the pollutant concentration will be higher and water quality will be degraded permanently (Damardji et al. 2009).
Synergistic effect of CTAB on Reactive Black 5 removal performance of Candida tropicalis
Published in Bioremediation Journal, 2023
Ekin Demiray, Hande Günan Yücel, Hatice Elçin Özkuzucu, Sevgi Ertuğrul Karatay, Zümriye Aksu, Gönül Dönmez
Dyes are important products for the textile, plastic, pharmaceutical and cosmetic industries. It is estimated that more than 7 × 105 tons of synthetic dyes are produced annually in the world (Yang et al. 2011). Due to their complex aromatic nature, these dyes are highly stable and non-biodegradable, making their waste undesirable for the environment (Vijayaraghavan and Yun 2007; Bounaas et al. 2019). On the other hand, the toxic, carcinogenic, mutagenic and allergic properties of synthetic dyes have negative effects on humans, animals and plants. Moreover, they can inhibit photosynthesis and light penetration in aquatic systems. For these reasons, reactive dyes in effluents should be removed from the environment and wastewater.