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The Study of the Effect of UV-C Radiation on the Current–Voltage Characteristics of Chitosan Membranes
Published in Pandit B. Vidyasagar, Sagar S. Jagtap, Omprakash Yemul, Radiation in Medicine and Biology, 2017
Ni Nyoman Rupiasih, Made Sumadiyasa, Putu Erika Winasri
The numerous membranes have been developed for use in reverse osmosis, nanofiltration, ultrafiltration, microfiltration, pervaporation separation, and electrodialysis and in medical use such as artificial kidney [6]. Among these membranes, ion-exchange membranes are one of the advanced separation membranes. It has been used not only as electrodialysis concentration or desalting of solutions, diffusion dialysis to recover acids and electrolysis of sodium chloride solution but also in various fields as a polymeric film having ionic groups [7].
Chemical hazards *
Published in Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse, Routledge Handbook of Water and Health, 2015
Lisa Smeester, Andrew E. Yosim, Rebecca C. Fry
A number of technologies can be used to ensure the selenium content of drinking water is minimized, including membrane filtration, electrodialysis, ion exchange and adsorbents such as activated alumina (Kapoor et al., 1995; WHO, 2011c). Other options include using alternative sources, and blending low-selenium sources with high-selenium sources.
Impact of pH conditions and the characteristics of two electrodialysis membranes on biofilm development under semi-realistic conditions
Published in Biofouling, 2021
Jörg Böllmann, Marion Martienssen
To investigate the impact of different and partially extreme pH conditions and the influence of different membrane characteristics on biofilm development, two different electrodialysis membranes, a strongly alkaline anion exchange membrane (AEM) and a strongly acidic cation exchange membrane (CEM), were incubated in real treated wastewater at a pH range from 4 to 11. This could generate complex biofilms at semi-realistic and more relevant conditions in contrast with many previous studies, which investigated biofilms of defined bacteria consortia on more standardized surfaces (Christensen et al. 1985; Daniels et al. 2013; Van den Driessche et al. 2014; Ommen et al. 2017) or studied membrane fouling with synthetic organic foulants (Lee et al. 2009). These studies are necessary to test measurement methods and gain further understanding of biofilm development, but might not reflect the challenges of biofilm characterization and membrane fouling under more realistic conditions with complex bacterial consortia. The results of this study can help to predict the long-term performance of the membranes during the electrodialysis process with respect to biofilm development, and the need for maintenance and cleaning, and can support process optimization.
The effects of heavy metals on human metabolism
Published in Toxicology Mechanisms and Methods, 2020
This article discusses the various hazards associated with heavy metal exposure on human metabolism. However, it is important to understand the methods by which the public come into contact with heavy metals, in order to avoid further contact. Based on previous research results, for many people regulatory limits have been exceeded and they are at the threshold of developing major organ toxicity. Governments must therefore take important steps to protect the population from this potential hazard to people’s health by advising people to avoid fish species that contain high levels of arsenic and mercury(Salnikow and Zhitkovich 2008). Therefore, contaminated water must be treated before it can be released into the environment to ensure that safe drinking water is available to the public. In terms of agricultural safety, arsenic-containing herbicides should be replaced by safer alternatives. Unlike Amalgam fillings, dental composite fillings should always be used. Removal of heavy metals from water can be done through ion exchange (Tariq et al. 2008), adsorption, membrane filtration and electrodialysis (Chen 2004). Therefore, we need to establish a defense mechanism to prevent exposure to heavy metals, which increases the content of reactive oxygen species (Ros) in the human body and eventually induces a series of oxidative damage processes. In future, more research is needed to ensure that human health is protected and is safe from the effects and hazards of heavy metals.
Optimum isotherm by linear and nonlinear regression methods for lead (II) ions adsorption from aqueous solutions using synthesized coconut shell–activated carbon (SCSAC)
Published in Toxin Reviews, 2021
Onyedikachi Godwin Okpara, Osareme Mercy Ogbeide, Ozoemena Christain Ike, Kosoluchi Chisom Menechukwu, Eric Chidozie Ejike
Many methods have been developed for the treatment and removal of heavy metals concentrations. These methods are expensive, time-consuming, differ in their efficiency, some can generate toxic sludge, while some requires higher energy. The methods includes; filtration, ultra-filtration, electrodialysis, chemical precipitation, ion exchange, reverse osmosis, sedimentation, solvent extraction, electrochemical deposition, coagulation and adsorption (Samiey et al. 2014, Masindi and Muedi 2018). However, the above conventional methods are not economically viable for small and medium size industries due to huge capital required (Eruola and Ogunyemi 2014). It is therefore necessary to search for low-cost alternative techniques that may be effective, economical and sludge free (Mandina 2013). Adsorption using activated carbon, a phase transfer process is suitable and has been widely used in practice to remove organic and inorganic contaminants from fluid phases (Rashed 2013), it had proven economically viable, effective and simple to design. Different adsorbents had been used to adsorbed Pb(II) from aqueous solutions as reported by different authors (Gueu et al. 2007, Dwivedi et al. 2008, Giraldo and Moreno-Pirajan 2008, Calero et al. 2009, Kumar et al. 2010, Nuithitikul et al. 2020). And different works have been also published on adsorption efficiency of unsynthesized activated carbon produced from coconut shell (Goel et al. 2004, Sekhar 2008, Sartape et al. 2012, Bernard et al. 2013, Song et al. 2013, Sharaf El-Deen and Sharaf El-Deen 2016, Saputro et al. 2019). Moreover, the global interest in adsorption technology has broadened to the extent of considering various synthetic adsorbents (both carbonaceous and polymeric adsorbents) (Kyriakopoulos and Doulia 2006) as potential alternatives to compliment the activated carbon. The purpose of this synthesis is to increase more the durability, strength, selectivity, functional groups, surface area and pore parameters of the activated carbon to the required standard. On the other hand, the efficiency of adsorption depends on these properties mentioned. The carbonaceous synthetic adsorbents have been reported to be most widely used for removal of inorganic pollutants, low-molecular-weight halogenated hydrocarbon (van Vliet and Weber 1981) and to reduce the emission of organic pollutants from incinerated plants (Inoue and Kawamoto 2005), while the synthetic polymeric adsorbents made from materials similar to plastic such as; polyethylene, polypropylene, polyurethane foam, polyester foam, nylon fibers, polystyrene and polysiloxane (Ndimele et al.2018) are capable of binding the targeted metallic molecules, thereby removing unwanted heavy metals from contaminated water with a high affinity and selectivity.