Soil Application of Zeolite Affects Inorganic Nitrogen, Water Soluble and Exchangeable Potassium

An incubation study was conducted at college of agriculture, rajendranagar, PJTSAU to evaluate the influence of zeolite application on inorganic nitrogen, water soluble and exchangeable potassium in soil. Clinoptilolite Zeolite was fully mixed with soil (7.5 t ha-1) at the start of the experiment. Nitrogen was applied to soil through urea (200 kg ha-l). The experiment was conducted for 35 days and soil was analyzed for inorganic nitrogen, water soluble and exchangeable potassium at weekly intervals i.e., 1, 7, 14, 21, 28, 35 days of incubation. The results indicated that the treatment with zeolite application showed significantly higher ammoniacal nitrogen from day 1 (136.54 mg kg-l) to day 35 (38.71 mg kg-l) as well as nitrate nitrogen (day 1 – 59.13 mg kg-l; day 35 – 130.13 mg kg-l). Similarly water soluble (day 1 – 92.21 kg ha-l; day 35 – 103.13 kg ha-l) and exchangeable potassium (day 1 – 363.69 kg ha-l; day 35 – 393.94 kg ha-l) was also significantly higher in zeolite applied treatments. Thus, mixing of zeolite into soil improves inorganic nitrogen through reducing leaching losses and also improves water soluble and exchangeable potassium.

Interzeolitic Transformation of Clinoptilolite into GIS and LTA Zeolite

A natural clinoptilolite zeolite was transformed into other zeolites of greater industrial interest, such as zeolites with GIS and LTA structures. The synthesis conditions were studied, and the interzeolitic transformation was characterized by X-ray diffraction (XRD), X-ray fluorescence (FRX), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). From the results, it was possible to observe that the GIS and LTA zeolites were successfully synthesized. Furthermore, the results revealed that a synthesis time of 4 days was enough to obtain the GIS structure, and 4 h was sufficient to obtain LTA. The interzeolitic transformation can be explained by the RBU (Ring Building Unit) approach using C4 units from the HEU topology. The use of clinoptilolite in the synthesis of other zeolites is an innovative, economically viable, and environmentally sustainable process that exploits a material that exists in large quantities and is still little explored by industry.

Laboratory investigation of arsenic removal from the aquatic environment using nano adsorbents extracted from native zeolite

The presence of arsenic in water is a major problem in communities due to its toxicity and hazard. The aim of this study was to evaluate the removal efficiency of arsenic by CTAB-modified clinoptilolite zeolite from aqueous solution. The effect of contact time, pH, ionic strength, zeolite dose and CTAB concentration on arsenic removal were investigated. Structural analysis of XRD showed that the adsorbent used in this study was composed of clinoptilolite due to three strong peaks in 9.8, 22 and 27 degrees with intervals of 8.9, 3.9 and 3.1. Optimum condition for effective adsorption were obtained at pH = 3, zeolite dose of 5 g L–1, CTAB concentration of 5 mM, ionic strength of 0.1 M sodium chloride and contact time of 10 minutes. This study suggested that, the CTAB modified zeolite can be used as an effective and inexpensive adsorbent to remove arsenic from aqueous solutions, since it is a low-cost, abundant and locally available.

Removal of Toluidine Blue and Safranin O from Single and Binary Solutions Using Zeolite

The studies on dye removal from solutions attracted great attention due to the increased use of color dyes in different fields. However, most of the studies were focused on dye removal from a single solution. In reality, wastewater from the fabric industry could contain mixed dyes. As such, evaluating different dye removal from mixed solutions may have more practical importance. In terms of sorbents evaluated for dye removal, most of them were an organic type generated from agricultural wastes. Clay minerals and zeolites were also studied extensively, because of the vast reserves, inexpensive material cost, larger specific surface area (SSA) and high cation exchange capacity (CEC). However, evaluating the factors controlling the dye removal from mixed dye solutions was limited. In this study, the removal of cationic dyes safranin O (SO) and toluidine blue (TB) by clinoptilolite zeolite (ZEO) was evaluated under single and binary systems. The results showed that removal of TB was preferred over SO by approximately a 2:1 ratio. The counterion Cl− sorption from mixed dye solution helped the formation of mixed dye aggregates on mineral surfaces. Molecular dynamic simulation confirmed the multilayer mixed dye formation on ZEO under high loading levels.

Mitigating Potassium Leaching from Muriate of Potash in a Tropical Peat Soil Using Clinoptilolite Zeolite, Forest Litter Compost, and Chicken Litter Biochar

Using muriate of potash (MOP) as a source of potassium (K) is a cost-effective method for crop production in tropical peat soils. However, exchangeable K commonly leaches from tropical peat soils because of high rainfall and a lack of clay to retain this cation. Potassium retention as exchangeable K could inhibit K loss through leaching to increase K availability. Clinoptilolite zeolite (CZ), forest litter compost (FLC), and chicken litter biochar (CLB) can be used to retain K from MOP in tropical peat soils for crop use because of the high affinity of CZ, FLC, and CLB for K ions. These approaches can be used as innovative and sustainable alternatives for the frequently used lime (CaCO3). However, information on using CZ, FLC, and CLB for MOP K retention is limited. Thus, CZ, FLC, and CLB were tested in a leaching study to determine their effects on MOP K retention in tropical peat soil. The use of CZ and FLC at rates of 100% and 75% of the recommended rate for pineapple cultivation (a commonly grown fruit crop in tropical peat soils in Malaysia) improved the K availability, pH, and CEC of the peat soil because of the high CEC of CZ and the humic substances (humic acids, fulvic acids, and humin) of FLC, which have a high affinity for K ions. The CLB did not improve K retention because of the competition between K, Ca, Mg, and Na ions, which are inherently high in this soil amendment. Instead of liming, which only replaces a few of the leached cations, such as calcium, the results of this study suggest an alternative method of retaining peat cations, such as K, that reduce peat acidity. This alternative method of retaining peat soil cations, especially K ions, is a practical and sustainable approach for improving peat soil productivity.