The potential usage of zeolites as adsorbents for the removal of organic molecules from water was investigated in a series of experiments with aqueous solutions of lower alcohols. This could represent a simple solution to the problem of cleaning up industrial wastewater as well as recovering valuable chemicals at relatively low costs. Adsorption isotherms of the Langmuir type were applied, and calculations showed that the amount of propanol adsorbed on silicalite corresponded to approximately 70% of the pore volume. The adsorption process is simple, and recovery of the more concentrated products is easily done by heat treatment and/or at lowered pressures. Adsorption experiments with aqueous acetone showed that silicalite had approximately the same adsorption capacity for acetone as for n-propanol. Heats of adsorption were determined calorimetrically
The first experimental works for adsorption of gases on zeolites and the influence of molecular-sieve properties was made on natural materials by F. Gradian who studied adsorption of gases on dehydratited zeolites. The ability of adsorption properties of the zeolites is determined by two factors, character of the porous structure and the heteropolar character of the polar centers. In our research adsorption is determined with water vapor by a static-gravimetric method. The results are presented in tables and graphic dependence is represented by adsorption isotherms in Langmuir 's coordinates.
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Many of the sweeteners are randomly discovered and have virtually nothing to do with the sugar molecule, but they can bind to the same receptors that are responsible for the taste and the population to create a sense of sweetness. Increased use of sweeteners can create an excessive amount of sweet foods, or unconsciously increase the intake of carbohydrates in the body. Aspartame is one of the most used sweeteners. Aspartame is a methyl ester dipeptide consisting of aspartic acid and phenyalanine. It is encountered in two shapes a and shape b, of which the shape a is sweet. Aspartame is about 200 times more sweetened than sucrose. The use of aspartame is widely approved in foodstuffs. Aspartame is the subject of numerous scientific research both in terms of its structure and its carcinogenicity. In this paper, the structure of aspartame will be described in detail, its properties, and its application as a food additive.
Zeolites are sodium alumino silicates which in in their composition contain zeolite water. They have a three-dimensional structure. Spatial structure defined by a strictly defined geometry of pores and cavities. For ionic еchange is used magnesium salt (MgCl 2 *6H 2 O) whose aqueous solutions were with the following concentrations (MgCl 2 *6H 2 O) = 2,5; 3.5; 4,5 mol / dm 3 , and other parameters of the ion exchange: time t = 20, 30, 40 and temperature of 298 and 330 K. Ionian capacity is calculated as mmgMgO / 1g zeolite.
Radioactive hazardous solid waste occurs with the use of radioisotopes in medical centers and industry, and there are certain amounts of radioactive lightning rods in our country, but more specific knowledge about the quantities of this waste is not known. There are no official collection systems for radioactive waste and there are no disposal facilities. Radioactive waste is small and consists of radioactive materials, usually subject to several legal provisions such as: collection, disposal and finally disposal of radioactive materials in human environment, regulations for the circulation and use of radioactive materials through a certain limit, X-ray devices and other devices that generate ionizing rays and protective measures from these rays. Priorities regarding radioactive waste management are: development of capacity for permanent storage of low and intermediate level radioactive emissions sources in accordance with the existing legal provisions for control and management of radioactive emissions and exposure of the public to them. This paper will describe in detail the radioactivity, radioactive waste, the increase in water temperature as a result of the use of nuclear reactors, the impact of nuclear reactors on water, as well as the way of storing and delaying radioactive waste, as well as the negative consequences caused by the radioactive waste.
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