Synthesis of zeolites and their applications as Ion exchange to remove water hardness

The minimal contact time in removal of ammonia ions by ion-exchange with zeolite, Na-form, is determined using the method of differential element. The relationship between the contact time, the water velocity, the effect of removal and the initial ammonia concentration is investigated. The obtained data serve as a basis for mathematical modeling of the ion exchange kinetics and give valuable information about some design parameters of ion-exchange facilities. Some basic analyses, concerning the desorption of ammonia from zeolite, induced mainly from the cations naturally present in surface waters are made. The influence of water velocity and water hardness on such desorption is investigated. These experimental data and analyses are an essential part of a study, the purpose of which is to investigate the possibilities for ammonia removal and biological regeneration of zeolite in a combined facility, using the processes: ion-exchange, desorption induced by small concentrations of cations and biological nitrification.

Download Full-text

Sorption and Membrane Technologies for Mine Water Purification

Materials Science Forum ◽

10.4028/www.scientific.net/msf.946.621 ◽

2019 ◽

Vol 946 ◽

pp. 621-627

Author(s):

Konstantin L. Timofeev ◽

Vasilii Kurdiumov ◽

Gennady Maltsev

Keyword(s):

Ion Exchange ◽

Reverse Osmosis ◽

Water Purification ◽

Mine Water ◽

Large Scale ◽

Potable Water ◽

Water Hardness ◽

Membrane Technologies ◽

Large Scale Tests

The importance of the research is due to the lack of potable water (~1.6 million m3 per year) in a rapidly developing city in the Urals. One way to solve this problem is to purify water from the spent copper mine with a debit of ~4.4 million m3 of water per year. The most advanced techniques recently used for obtaining drinking water of a high quality are based on ion exchange and reverse osmosis, which can ensure an obtainment of water with initial contents of impurities much below the maximum permissible values. Based on the real experience the article compares sorption and membrane technologies in terms of water purification efficiency and cost of potable water production. The large-scale tests of mine water purification were carried out at sorption and reverse osmosis pilot plants with the capacity of 1 m3 per hour for the incoming flow. The source water had the following composition, mg/dm3: 0.5–0.9 Mn; 1.0–1.7 Ni; 80-140 Ca; 30-40 Na; 40-70 Mg; 0.2–0.6 Cu; 8.1–9.5 Si; 0.01–0.03 Zn; 0.01–1.70 Fe; <0.01 Al; < 0.005 As; < 0.005 Pb. At the same time the salinity was 640–680 mg/dm3, the water hardness was 9.5–11.5 mmol/dm3 and pH was 7.0-7.5. The content of non-mentioned impurities was below the detection limit. The resulting treated water met the requirements for the quality of potable water for both purification techniques. It was concluded, that the best option for treatment of mine water is ion exchange.

Download Full-text

Food Soils, Water Hardness, and Alkaline Cleaner Formulations

Journal of Milk and Food Technology ◽

10.4315/0022-2747-38.3.163 ◽

1975 ◽

Vol 38 (3) ◽

pp. 163-165 ◽

Cited By ~ 3

Author(s):

G. H. WATROUS

Keyword(s):

Ion Exchange ◽

Food Processing ◽

Soil Removal ◽

Water Solution ◽

Water Hardness ◽

Hard Water ◽

Processing Equipment ◽

Commercial Detergents ◽

Specific Food

Cleaning of food processing equipment involves the proper interrelationship between ingredients in cleaners formulated for specific food soils and the detergent solvent, usually water. Solution temperatures and times are critical for efficient soil removal. Many commercial detergents contain large amounts of phosphorus, usually as polyphosphates, so they can be used with very hard water. Ion exchange units to remove objectionable cations from water will permit use of cheaper cleaners that contribute less phosphorus to the environment.

Download Full-text

Influence of water hardness on removal of copper ions by ion-exchange-assisted electrodialysis

Desalination ◽

10.1016/s0011-9164(04)00048-7 ◽

2004 ◽

Vol 162 ◽

pp. 249-254 ◽

Cited By ~ 20

Author(s):

S.L Vasilyuk ◽

T.V Maltseva ◽

V.N Belyakov

Keyword(s):

Ion Exchange ◽

Copper Ions ◽

Water Hardness ◽

Influence Of Water

Download Full-text

Embedding Procedure for Water Swollen Samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006951x ◽

1970 ◽

Vol 28 ◽

pp. 504-505

Author(s):

Ann M. Thomas ◽

Virginia Shemeley

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Ion Exchange ◽

Structural Changes ◽

Cross Linking ◽

Ion Exchange Resins ◽

Transmission Electron ◽

First Pass ◽

Exchange Resins

Those samples which swell rapidly when exposed to water are, at best, difficult to section for transmission electron microscopy. Some materials literally burst out of the embedding block with the first pass by the knife, and even the most rapid cutting cycle produces sections of limited value. Many ion exchange resins swell in water; some undergo irreversible structural changes when dried. We developed our embedding procedure to handle this type of sample, but it should be applicable to many materials that present similar sectioning difficulties.The purpose of our embedding procedure is to build up a cross-linking network throughout the sample, while it is in a water swollen state. Our procedure was suggested to us by the work of Rosenberg, where he mentioned the formation of a tridimensional structure by the polymerization of the GMA biproduct, triglycol dimethacrylate.

Download Full-text