Nanotechnology is one of the extensively high advanced technologies of the world and emerging in haste with its entire span and has a diversified use. Titanium dioxide (TiO2) has been extensively studied as a photocatalyst in nanotechnology for different applications such as water and air remedy, because of its relatively high photocatalytic activity, robust chemical stability, relatively low production costs, and non toxicity. Nano-structured TiO2 was synthesized using sol-gel method with and without presence of nano porous polymer . Photocatalytic efficiency of the samples have been characterized by several techniques (SEM, EDS, UV Spectroscopy and XRD). This photocatalytic process might be effective to remove this color and minimize the cost of an effluent treatment plant.
The organic dyes are toxic to water, soil and plant. The conventional methods for dye effluent treatment are not able to classify the soil polluting, plant toxic and water polluting organic dyes. In this book, water polluting, soil polluting and plant toxic organic dyes are classified. The soil and plant materials are having oxygen atom in its chemical structure. The lone pair of electron present in the oxygen atom plays a chemical force to attract the cationic dyes. Hence, cationic dyes chemisorbed on soil and plant materials. Therefore cationic dyes are soil and plant toxic. The anionic dyes are repelled by the lone pair of electrons present in the oxygen atom. Hence, the anionic dyes are not able to chemisorb on soil and plant material. Then the anionic dyes are being in water and so it is water polluting. The cationic dyes chemisorbed on soil and plant are loss its chemical properties and it may biodegradable slowly. So the water polluting organic dyes directly affect the human health through drinking water. A new nano porous solid acid material is synthesised and applied to remove the organic dyes from aqueous solution. The material is green material and reusable.
Nuclear Magnetic Resonance (NMR) has become a well-established method in many different areas of research. The scope of the disciplines involved is extremely broad, but the power of NMR, lies in its ability to combine and extend the available techniques for a more thorough solution of problems which cannot be assigned to one of the popular categories.In the world of chemical engineering, every chemical process is designed to produce economically a desired product from a variety of starting materials through a succession of treatment steps. Frequently, the chemical treatment step (typically areaction taking place inside a reactor) is the hearth of the process, that makes or breaks the process economically. Heterogeneous Catalytic reactions play an important role in many industrial processes. It is estimated that well over 50 % of all the chemieals produced today are made with the use of catalysts. The rate constants of the heterogeneous catalytic reactions, and therefore the efficiency of the reaction, depends on several parameters. Therefore, the development and optimization of the catalyst becomes an important part of the design of a chemical process, and much effort and money are invested in that direction.The work presented here consists in a combination of different aspects of Nuclear Magnetic Resonance, focused on providing a reliable tool for the optimization of chemical processes, via the on-line monitoring of catalytic reactions. For that purpose, the following decomposition, was studied as a model reaction: 2H202 (liquid) -> + 2H20 + O2 (gas). The election of the decomposition of aqueous hydrogen peroxide solutions relies on two main reasons. Firstly, the fact that the reaction can be carried out in a simple laboratory glass tube, under room temperature and atmospheric pressure with occurrence of the gas phase in form of bubbles, makes it an excellent example of a simple liquid-gas reaction. Secondly, hydrogen peroxide has itself a huge importance as a chemical compound. It is one of the most versatile and environmentally desirable chemieals available today, used in a wide variety of industrial applications, from chemical synthesis to the treatment of pollutants, also including the synthesis of conjugated polymers and its use as a green propellant for space propulsion.The results presented along this work include: the feasibility of using the time dependence of the effective diffusion coefficient in the vicinity of the catalysts to monitor the decomposition with relatively high temporal resolution for several hours, the possibility of making use of the influence of two-site chemical exchange between protons in water and hydrogen peroxide on the transverse relaxation time, together with pH, to obtain a quantification of the H202 concentration during the reaction, in the liquid surrounding the catalyst, the use of the chemical exchange as a source of contrast in NMR Imaging, providing a tool for monitoring the reaction with spatial resolution inside a porous particle.
Colloids refer to particles or macromolecules with at least one dimension of 1nm~1µm. A wide range of environmental particles fall within this category including microorganisms, nanoparticles, and mineral precipitates. Understanding colloid fate and transport in porous medium not only permits more effective protection of water supplies, but also allows for the development of more effective pollutant remediation strategies. Organic matter (OM) complicates colloid behaviour. To date the influence of OM on colloid mobility in porous media has been largely qualitative. This book presents research leading to the development of multiple-pulse column techniques that may be integrated with mathematical models to quantify the effects of OM on particulate colloid attenuation in saturated porous medium. Research has investigated how two groups of environmental organic compounds, humic acids and proteins, influence particulate colloid attenuation by saturated sand. Study findings may shed light on complex colloidal behaviour in organic matter impacted environment and be useful to professionals in contaminant hydrogeology, environmental remediation, and wastewater treatment.
In the area of water purification, nanotechnology offers the possibility of an efficient removal of pollutants and germs. Globally, water scarcity is one of the foremost health and environmental challenges faced. Today nanoparticles, nanomembrane and nanopowder used for detection and removal of chemical and biological substances include metals such as copper, lead, nickel, zinc, bacteria, parasites and antibiotics. Nanomaterials reveal good result than other techniques used in water treatment because of its high surface area (surface/volume ratio). It is suggested that these may be used in future at large scale water purification. Electrospinning technique has drawn a lot of interests from many researchers these days. One of the advantages of this technique is in effectively preparing nano size fibers from various organic and inorganic materials which do not form fibers by conventional methods. Nanofibers prepared using electrospinning have been used in many applications due to their large surface area and porous structure.
Adsorption is one of the suitable, ancient and effective water treatment method. In spite of these facts, adsorption has certain limitations, such as yet it could not achieve a good status, probably, due to lack of suitable adsorbents. Moreover, adsorption process is based on the transportation and diffusion of the guest objects, reducing the pathway and resistance can facilitate molecules into the porous carbon materials. The reduced pathway depends on the porous nature of carbon materials. However, synthesis of porous carbon materials with a desired porous network, which can reduce the contact time of adsorbent and adsorbet, is still a great challenge. Thus In this book pore of carbon materials was synthetically controlled to tackle the above-stated lacuna in existing adsorbents by the choice of carbon and polymeric source and applied for the removal of highly hazardous organic water pollutants. The work presented in this book describes the importance of pore and their fabrication synthetically as well as solving the environmental problems like water purification by using synthesized hierarchical carbon materials adsorbent.
In this book, the environmental application and implication of nanoscale zerovlanet iron (NZVI) are studied. Reduction and removal of Bromate and TCE DNAPL using NZVI were evaluated for drinking water treatment and groundwater remediation. A visualization technique for TCE DNAPL removal using reactive NZVI and bimetallic nanoparticles was conducted using a glass micromodel with a view toward improved contaminant displacement. Inert/pseudo-inert gases, including argon, nitrogen, and carbon dioxide, were utilized to stabilize synthesized NZVI after lyophilization to prevent self-ignition. In addition, the aging effect was investigated for these stabilized NZVI both in humid and dry conditions. A new and simple method was proposed for encapsulating NZVI using poly (vinyl pyrrolidone) (PVP) nanofibrous membranes by an electrospinning technology to maintain catalytic activity. At last, mobilization and deposition of NZVI in a porous medium were observed using a water-saturated glass micromodel, a high-resolution microscope was utilized to visualize the transport phenomena of microscopic aggregations of NZVI inside the micromodel.
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Potassium alum or potash alum is the potassium double sulfate of aluminium. Its chemical formula is KAl(SO4)2 and it is commonly found in its dodecahydrate form as KAl(SO4)2·12(H2O). It is commonly used in water purification, leather tanning, fireproof textiles, and baking powder. It also has cosmetic uses as a deodorant and as an aftershave treatment. Potassium alum crystallizes in regular octahedra with flattened corners, and is very soluble in water. The solution reddens litmus and is an astringent. When heated to nearly a red heat it gives a porous, friable mass which is known as "burnt alum." It fuses at 92 °C in its own water of crystallization.
In this work, the experimental characterization of gas diffusion material for PEM fuel cells is carried out. Properties such as porosity, capillary pressure curves, absolute permeability, and relative permeability were obtained for carbon paper Toray-090. Experimental fixtures and procedures used to characterize the porous material are presented. The effects of PTFE treatment (wet-proofing) and compression on the porous media properties were assessed. After characterizing the porous media material, two computational models of the air-cathode of a PEM fuel cell were developed using the gas diffusion media properties obtained. The hypothesis presented in this work is that cell performance can be accurately predicted using actual water transport characteristics of the GDL material instead of empirical correlations for well-sorted sands as reported by many authors.