ION EXCHANGE RESIN
Ion exchange resin works by removing ionized species from water by exchanging these species for H+ and OH- ions. These resins have minute pore size of around 1 mm with large sites for ionic groups to exchange in the resins. The method on how the ion exchange resin works and regenerated is as illustrated in Figure 1.1.
Figure1.1: working cycle of ion exchange resin
Currently, there are two methods for ion exchange to work where one is a batch and the other is a column method. For the batch method, the resin and solution is mixed and then stirred in a vessel where the ionic exchange is allowed to take place until equilibrium. Once equilibrium is reached, the resin is removed from the solution and the degree of exchange is determined by the selectivity of the resin itself towards the ions in the solution. Thus, the capacity of the resin is limited by the selectivity which is as illustrated in Table 1.1 below. A batch processing is not favoured due to the low efficiency in the regeneration process.
Table 1.1: Types of Ion Exchange Resins with Decreasing Preferences.
Strong Acid Cation Exchanger Strong Base Anion Exchanger
Barium Iodide
Lead Nitrate
Calcium Bisulfite
Nickel Chloride
Cadmium Cyanide
Copper Bicarbonate
Zinc Hydroxide
Magnesium Fluoride
Potassium Sulfate
Ammonia Sodium
Hydrogen
On the other hand, a column process works similar to a plug flow reactor where it is like treating the solution through infinite numbers of batch tank. Column process is much preferred due to the high efficiency and lower reactor size to achieve the same conversion as compared to a batch process. Even using a resin with low selectivity for the ions in the solution, desired degree of separation is still possible.
Selecti...
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...pposite of the recycle method since this process goes from strong brine to weak brine regeneration. Whenever high concentration of iron or manganese is present in the ion exchange fluid, this process is not practical due to the valence electron charges of iron and manganese to that of brine.
References
1) Sharon O’ Skipton. (2008). Drinking Water Treatment: Water Softening (Ion Exchange). University of Nebraska Institute of Agriculture and Natural Resources.
2) International Atomic Energy Agency. (2002). Application of Ion Exchange Processes for the Treatment of Radioactive Waste and Management of Spent Ion Exchangers: Technical Reports Series 408. VIC Library ISSN 0074-1914
3) Remco Engineering. (n.d.). Ion Exchange: Basic Concepts. Available on www.remco.com/ix.htm
4) ELGA. (2012). How does an Ion Exchanger Work. Available on www.elgawater.com/ion-exchanger-en
As shown in Fig. 5, the final pH of the NaClO-NH3 solution after simultaneous removal are 5.4, 6.9, 7.2, 7.5, 8.5, 9.6, 10.7, 11.5 and 12.8 with respect to the initial pH of 5, 6, 7, 8, 9, 10, 11, 12 and 13, from which, an interesting law can be concluded as that if the initial pH is an acidic, the final pH is slightly increased; but if the initial pH is an alkaline, the final pH is declined. NaClO-NH3 is macromolecule compounds with a large inter surface area. It contains abundant functional groups such as hydroxyl (OH), carboxyl (COO), quinone, amino (–NH2), etc, which determines that NaClO-NH3 is a salt of strong base and weak acid, as well the ionization equilibrium and hydrolytic equilibrium would be complicated. When the pH of the NaClO-NH3 solution was acidic, the functional groups such as OH, COO and NH2- would react with H+ to generate the NH3 sediment, resulting in a decrease of inter surface area owing to the block and a great loss of NaClO-NH3, then the NOx removal as well as the duration time was decreased. As for the increase of the final pH in the acidic conditions, this was a result of the consumption of H+ by NaClO. The decrease of the
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
In the first part of this project, two cation elimination tests and one cation confirmation test were performed. 10 drops of 4 cation solutions: potassium, zinc(II), copper(II)
Ionic liquids (ILs) are liquids composed entirely of ions. Molten salt is the term normally reserved for those systems that are liquid at high temperatures, for example NaCl (table salt is a liquid at ≈ 800 0C). Room-temperature ILs are liquid below 100˚C, have received considerable attention as substitutes for volatile organic solvents. Due to their remarkable properties, such as negligible vapour pressure, large liquidous range, high thermal stability, good ionic conductivity, high electrochemical stability, they are considered favourable medium candidates for chemical syntheses. ILs are usually categorized into four types based on their cation segment: 1) alkylammonium-, 2) dialkylimidazolium-, 3) phosphonium- and 4) N-alkylpyridiniumbased ILs (Figure 1). Ionic liquids are generally composed of a bulky organic cation, such 1-butyl-3 methylimidazolium and typically an inorganic anion such as a halide. Below are the chemical structures of some common cations and anions used to make ILs.
The drawing demonstrates a film design with exchanging cation-particular (1) and anion-specific (2) layers. A cation-specific film (cation-trade layer) allows just positive particles to move through it. An anion-particular film (anion-trade layer) allows just entry to adversely charged particles. At every end of the layer stack, terminals (a cathode (3) and an anode (4)) are put, supplying an all-around circulated electrical field of direct current over the film stack. Between each film, spacers are set. Spacers ensure that there is room between films for the fluid procedure streams to stream along the layer surfaces.
The contraction moulding method can be used to process an acrylic denture base. In this method, bite blocks are fabricated in the lab and sent to the clinic for patient trial. These are then received from the clinic and teeth are mounted onto the bite blocks. The wax is eliminated and teeth are pressurized and attached onto a gypsum mould. (McCabe and Walls. 2008.) Sodium alginate is applied onto the mould to act as a separator to prevent any monomer from the acrylic base seeping into the base and the mould. Acrylic PMMA is applied onto the mould and either heat-cured or auto-polymerized. Both of these curing methods form the...
The use and management of radioactive materials is not a topic that is generally discussed in abundance to everyday citizens. Many people do not know what radioactive waste is or even the effect that it can have on the human body. Radioactive waste is a type of waste that has some type of radioactive material inside of it. The managing of this radioactive waste is extremely important because it can cause damage to living tissue. Without a place to properly dispose of or contain, the radioactive waste can contaminate our water, food, air, or even our land. If this happened it would be detrimental to all human’s health, causing many different problems throughout the world not only with the health of the population, but problems with the environment as well. Therefore it is vital that we have somewhere to put these radioactive wastes.
...For olivine, a method of chemical and thermal extraction is commonly used. First, the ore is combined with concentrated sulfuric acid to a certain ratio that depends on the concentration of olivine. Secondly, the mixture obtained is heated up to 250 degrees Celsius for approximately 7.5 hours, these number can vary in large amount depending on the concentration of magnesium and iron in olivine. Finally, to finish the process, the mixture is dissolved in water and the olivine precipitates as a solid and is removed from the solution by filtration.
The impurity can be minimized by extracting an ionic liquid into an organic solvent and washing with small amounts of deionized water. Which is removed in a rotary evaporator. The liquid is later dried with a heating vacuum. This does not work with all types of ionic liquids.
Firstly, a burette was taken and rinsed with distilled water. Then it was rinsed using the provided NaOH solution.
The bacteria and wastewater is mixed in an aeration tank and therefore the contaminants are removed by action of sorption and series of breakdown by the bacteria.
On repeating this experiment more care should be taken when purifying to remove the solvent impurities and minimise loss of crude product.
Ion exchange chromatography is a unique technique for effective separation of ions, amino acids, peptides, nucleotide and nucleic acids etc. This technique is widely used in the pre-fractionation or purification of a target protein from crude biological samples.
Abstract: Using Ion Exchange Chromatography, cellulase was purified. After purification, it was analyzed using a DNS test. The purified protein did not respond to the DNS the way it was expected to.
Clean water is needed for good human and animal health, but as DoSomething.org states, over 1 billion people worldwide don’t have a means of getting clean drinking water, an...