Softening of Hard Water by Bentonite Mineral
The paper reports and discusses the results of removal of hardness by Bentonite minerals. Hybridised IXfibres that contain dispersed hydrated ferric oxide (HFO) nano particles have also been reported for removal of hardness. Locally available bentonite minerals generally consist of montmorillonite. Besides useful adsorbent of ions in solution, bentonite is known for ion exchange. Bentonite is mixed well with water sample and time is allowed for ion exchange to take place. As a result calcium ion is exchanged. This ion exchange process here has been recognized for softening of water or benign removal of hardness. The particle size is of 0.3 m prepared in the laboratory. The main constituents of bentonite minerals are alumina, silica, iron oxide and oxides of sodium, potassium, calcium and magnesium. The bentonites have been found to be a natural exchanger. The cation exchange capacity of bentonite minerals may be attributed to the lattice structure as the clay minerals contain anions and cations in the exchangeable state. The bentonite minerals of 0.3 m size has been studied with different doses up to a certain interval of time and with fixed dose to different interval of time. The experiments were done by simple titration with N/50 HCl using methyl orange as an indicator.
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