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Golf Course Construction and Renovation
Published in L.B. (Bert) McCarty, Golf Turf Management, 2018
Zeolite/clinoptilolite. Zeolites are natural minerals noted for their very high cation-exchange capacity and low bulk densities. They have found widespread use in industry to remove environmental pollutants and as filtering and purifying agents, and have been introduced to the turfgrass market. Zeolites are mixed with sand primarily to increase cation-exchange capacity to improve nutrient retention, but in some cases may also improve aeration, drainage, and water-holding capacity. Due to their ability to bind cations (especially K), zeolite-based amendments may reduce nutrient leaching from porous sand rootzones. Additionally, they may be formulated to slowly release K and/or ammonium to the turf, and thereby help control nutrition levels. Commercial sources include Clinolite, Ecolite, EcoSand, EcoSand X, Zeoponix, and Zeopro. Zeopro is a zeolite with its cation exchange sites fortified with nutrients.
Utilization of natural clay minerals in the removal of ammonia from waste waters
Published in Gülhan Özbayoğlu, Çetin Hoşten, M. Ümit Atalay, Cahit Hiçyılmaz, A. İhsan Arol, Mineral Processing on the Verge of the 21st Century, 2017
H. Çiçek, F. Arslan, M.S. Çelik, M. Turan
There are 4.5 billion tons of natural zeolites, mainly clinoptilolite, in Turkey. In this study, ammonia adsorption capacity of Gördes clinoptilolite was investigated using bottle adsorption tests as a function of solid concentration, conditioning time, initial ammonia concentration, pH, temperature, and regeneration conditions using synthetic water containing NH4Cl. The performance of clinoptilolite is elaborated in view of industrial waste water treatment applications.
Synthesis and preliminary gas permeation properties of vitreous composite clinoptilolite membranes
Published in Chemical Engineering Communications, 2022
D. A. Kennedy, M. Mujčin, T. Omar, F. H. Tezel
Due to its extensive study with respect to adsorption based gas separation systems, the application of membranes formed of clinoptilolite is of interest in this work. Clinoptilolite is a common and abundant natural zeolite with a simplified chemical formula that is as follows: The framework structure consists of alternating eight and ten member rings formed of silica and alumina oxides (Mansouri et al. 2013). Therefore, charge balancing extra framework cations are necessary to balance the residual negative framework charge (this is represented by the X within the chemical formula which is equivalent to a + 1 charge cation) (Ackley et al. 1992; Mansouri et al. 2013). For natural clinoptilolite, this can be a variable mix of Ca2+, Mg2+ K+, and Na+ cations that is dependent on the source of the local mineral deposit (Koyama and Takéuchi 1977; Mansouri et al. 2013; Mumpton 1960). The channel pore arrangement is such that dimensions of the pore aperture may be altered by the arrangement of extra framework cations. This means that for the two parallel channels consisting of eight and ten membered rings; the effective channel window can vary in size from 3.1 to 7.5 Å and from 3.6 to 4.7 Å, respectively, whereas the effective pore size of the interesecting third channel ranges from 2.8 to 5.5 Å (Mansouri et al. 2013). The effect of different cations and alterations in the channel pore geometry induce favorable gas separation properties including molecular sieve effects (Ackley and Yang 1991a, 1991b; Aguilar-Armenta et al. 2001; Alver and Sakizci 2015; Jayaraman et al. 2004, 2005; Karousos et al. 2016; Kennedy et al. 2019a, 2019b, 2019c; Kouvelos et al. 2007; Predescu et al. 1995).