Zeolites, a group of minerals with unique properties, have been known for more than 250 years. However, it was the development of methods for hydrothermal synthesis of zeolites and their large-scale industrial applications (oil processing, agriculture, production of detergents and building materials, water treatment processes, etc.) that made them one of the most important materials of the 20th century, with great practical and research significance. The orderly, homogeneous crystalline and porous structure of zeolites, their susceptibility to various modifications, and their useful physicochemical properties contribute to the continuous expansion of their practical applications in both large-volume processes (ion exchange, adsorption, separation of mixture components, catalysis) and specialized ones (sensors). The following review of the knowledge available in the literature on zeolites aims to present the most important information on the properties, synthesis methods, and selected applications of this group of aluminosilicates. Special attention is given to the use of zeolites in agriculture and environmental protection.

The pretreatment of lignocellulosic material performed to improve substrate’s susceptibility to enzymatic hydrolysis is usually accompanied by reactions leading to the synthesis of compounds that inhibit the metabolic activity of microorganisms. Their toxicity is the main obstacle to the successful bioconversion of lignocellulosic hydrolysates. The identification of these inhibitors and the choice of the optimal detoxication method are crucial for the improving the efficiency of fermentation processes. Material rinsing with water after processing is a common detoxication practice. However, it generates material losses, thus affecting contents of saccharides in the fermentation medium, which may in turn trigger higher costs of lignocellulose conversion to ethanol and other products with a higher added value. A study was undertaken to determine the effect of selected methods for the detoxication of an enzymatic hydrolysate from Miscanthus giganteus on the fermentation efficiency of saccharide derivatives. The experiment conducted with Mucor rouxii DSM 1191 demonstrated the usability of the detoxication method based on the activated carbon. After 96-h fermentation of Miscanthus hydrolysates, the alcohol content in the post-reaction medium was higher by 14% than in the control experiment wherein the material was rinsed with water after pretreatment. The experiment carried out with Saccharomyces cerevisiae 7, NRRL 978 showed no positive impact of the alternative detoxication methods replacing material rinsing on the efficiency of ethanol synthesis. The highest concentration of this metabolite (2.04% (v/v)) was obtained in the experimental variant in which the mentioned operation was coupled with detoxication of hydrolysates using calcium hydroxide.

The aim of the study was to determine the effect of soil contamination with diesel oil (0, 5, 10 and 15 mL/kg d.m. of soil) on the macroelement content (nitrogen, phosphorus, potassium, sodium, magnesium and calcium) in the above-ground parts of oats (Avena sativa L.). A remediation effect of sludge as a substance which reduces the negative impact of this petroleum product on its element content in oats was also evaluated. Sewage sludge was applied in doses 0, 4, 8 and 12 g/kg of soil. The macroelement content in the above-ground parts of oats depended on the soil contamination with diesel oil and on the addition of sewage sludge to the soil. Soil contamination with diesel oil caused significant changes in the content of all macroelements in the above-ground biomass of oats. Increasing doses of the petroleum product in the series without sewage sludge decreased the content of all macroelements, except phosphorus and calcium. The highest effect was observed for the content of sodium in oats. The addition of sewage sludge to the soil alleviated the negative impact of diesel oil on the chemical composition of the plants. The application of sewage sludge to soil resulted in an increase in average content of nitrogen, sodium and magnesium (as opposed to phosphorus and partly calcium) in the above-ground parts of oats, compared to the series without sewage sludge.