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Ankit Beeyani, Kailash Singh, Raj Vyas, Shashi Kumar and Surendra Kumar

). Comparison of the adsorption dynamics of air on zeolite 5A and carbon molecular sieve beds. Korean Journal of Chemical Engineering 21(6), 1183-1192. DOI: 10.1007/BF02719492. Todd, R. S. & Webley, P. A. (2006). Mass-transfer models for rapid pressure swing adsorption simulation. AIChE Journal 52(9), 3126-3145. DOI: 10.1002/aic.10948. Ahari, J. S., Pakseresht, S., Mahdyarfar, M., Shokri, S., Zamani, Y., pour, A. N. & Naderi, F. (2006). Predictive Dynamic Model of Air Separation by Pressure Swing Adsorption. Chemical

Open access

Mária Valičková, Ján Derco and Katarína Šimovičová

Abstract

The paper is focused on the removal of selected priority hazardous substances. Five chlorinated pesticides, i.e. hexachlorobenzene (HCHB), hexachlorobutadiene (HCHBD), lindane (LIN), pentachlorobenzene (PCHB) and heptachlor (HCH) were selected as model pollutants. Higher volatility is characteristic for these substances. Adsorption of these pollutants on granular activated carbon (GAC), zeolite (Zeo) and activated sludge (AS) was investigated. The effect of contact time on the removal efficiency of studied substances was investigated. From results of the work it follows that the highest removal efficiency of studied substances was achieved by the adsorption on activated sludge. This was followed by adsorption efficiency on zeolite. The lowest removal efficiency was measured for adsorption on granular activated carbon.

Open access

Milena Kosiorek and Mirosław Wyszkowski

). Biology and Fertility of Soils 31(6): 522–524. Jayasinghe G.Y., Tokashiki Y., Kinjo K., Liyana-Arachchi I.D., 2010. Evaluation of the use of Synthetic Red Soil Aggregates (SRA) and zeolite as substrate for ornamental plant production. Journal of Plant Nutrition 33(14): 2120–2134. Kabata-Pendias A., Pendias H., 2001. Trace elements in soils and plants. 3 rd ed. CRC Press: Boca Raton, FL: 413 pp. Kosiorek M., Wyszkowski W., 2016a. Effect of neutralising substances on selected properties of soil contaminated with cobalt. Journal of Ecological Engineering

Open access

Jinghong Ma, Yuhong Kang, Ning Ma, Wenming Hao, Yan Wang and Ruifeng Li

Abstract

A high-acidity HUSY zeolite with mesoporous structure was prepared by alumination with a dilute aqueous NaAlO2 solution and characterized by XRD, N2 adsorption, IR framework vibration and 29Si MAS NMR methods. The results indicated the extra-framework aluminum was reinserted into the tetrahedral framework through isomorphic substitution of framework Si (0Al) sites by Al ions, whereas the crystal and micropore structure were unaltered. FTIR spectra of hydroxyl vibrations and pyridine adsorbed on realuminated zeolites showed that the number of Brønsted acid sites and strong Lewis acid sites increased whereas weak Lewis acid sites decreased twice. The mesoporous structure composed of inter-and intra-crystalline pores in the aluminated HUSY increased the external surface area of the zeolite, improving accessibility of molecules to the active sites and enhancing its catalytic ability. The realuminated HUSY zeolite supported with Ru catalyst exhibited a higher catalytic activity for benzene hydrogenation than the parent HUSY zeolite; the reaction rate in comparison to the mesozeolite increased by 5.5 times.

Open access

Agnieszka Marcewicz-Kuba and Danuta Olszewska

The influence of a hard coal type on the degree of sulphur dioxide removal

In this paper the authors have studied the properties of zeolite and montmorillonite doped with the nickel and cobalt cations in the removal of SO2 from the combustion gases process based on the DESONOX method. Burning coal from the hard coal from the Silesian Coal Basin mine "Julian" and the Lubelskie Coal Basin mine "Bogdanka" with supports only - did not show any reduction of the SO2 emission in the combustion gases.

Open access

F. Tutti, S. Kamyab, M. Barghi and A. Badiei

Abstract

In the present study, edingtonite has been extracted from natural zeolite clinoptilolite by simulating the natural hydrothermal conditions in the laboratory, under the influence of solutions with different concentrations of Ba+2 and Na+, varying from 0.5 to 2.8 mol/L, at 150 °C. In this work, the essential hydrothermal conditions have been provided by hydrothermal autoclaves. The natural and laboratory prepared samples were characterized by XRD, XRF and SEM methods.

Open access

Milutin Djordjević, Milorad Mirilović, Novica Stajković, Ljiljana Janković, Branislav Pešić, Dubravko Bokonjić and Spomenka Djurić

Abstract

Diflubezuron is increasingly used in areas where mosquito larvae developed resistance to other insecticides. In our community diflubenzuron is not used to control mosquito larvae. Two formulations of 1% diflubenzuron (on corn-cob EF-1, and zeolite EF-2) were tested on Culex pipiens L (larvae) on one canal in the Belgrade suburb area. The effect was followed for seven weeks after application of the formulations. Formulation EF1 achieved a reduction in mosquito L1L2 larvae between 23.9% and 89.4%. The change was statistically significant the 21st and 28th day (p<0.001), 35th and 42nd day (p<0.01) and 49th day (p<0.05). The maximal reduction obtained by formulation EF2 was 69.1%. The accomplished reduction was significant on the 28th and 42nd day (p<0.001), 35th day (p<0.01) and 21st (p<0.05). Both formulations have maintained a good residual effect on the lower developmental larval stages. Maximum reduction achieved by EF1 on L3L4 larvae was 97.4%. Reduction of larvae was high between the 7th and 42nd day (66.4 - 97%). Statistically significant values were recorded on the 21st, 28th and 35th day. Formulation EF2 achieved a reduction of 99.5%. A statistically significant reduction in the value of mosquito larvae was obtained on the 14th, 21st, 28th, 35th and 42nd day.

Between the two used formulations there was no significant difference in the number reduction of lower larval stages, but for the higher larval stages EF1 proved to be more efficient.

Open access

Anita Tarbuk, Ana Marija Grancarić and Mirna Šitum

(Serbian Soc. Chem. Ind. J.) 59(9-10), 230-234. [22] Grancarić, A. M., Tarbuk, A. (2009). EDA Modified PET Fabric Treated with Activated Natural Zeolite Nanoparticles, Materials Technology: Advan. Performance Materials, 24 (1); 58-63. [23] Cox Crews P., Zhou Y. (2004). The effect of wetness on the UVR transmission of woven fabrics. AATCC Review, 4(8), 41-43. [24] Riva, A., Algaba, I., Prieto, R. (2007). Optical Brightening Agents Based on Stilbene and Distyryl Biphenyl for the Improvement of Ultraviolet Protection of Cotton Fabrics, Tekstil 56 (1), 1

Open access

Selvakumar Dineshkumar, Ganesamoorthi Thirunarayanan, Perumal Mayavel and Inbasekaran Muthuvel

Abstract

Zeolite Y clay modified copper nitrate catalyst was prepared. The obtained catalyst was analyzed by SEM, EDS, and powder XRD techniques. The zeolite Y clay modified copper nitrate catalyst was used for the synthesis of various substituted mesalazine by sulfonylation. The synthesized sulfonamides have been characterized by GC-MS, IR, 1H, 13C and HSQC NMR techniques. The yield percentages of sulfonamides are more than 85%.

Open access

Kinga Kowalska and Bogdan Ambrożek

Abstract

The dynamic performance of cylindrical double-tube adsorption heat pump is numerically analysed using a non-equilibrium model, which takes into account both heat and mass transfer processes. The model includes conservation equations for: heat transfer in heating/cooling fluids, heat transfer in the metal tube, and heat and mass transfer in the adsorbent. The mathematical model is numerically solved using the method of lines. Numerical simulations are performed for the system water-zeolite 13X, chosen as the working pair. The effect of the evaporator and condenser temperatures on the adsorption and desorption kinetics is examined. The results of the numerical investigation show that both of these parameters have a significant effect on the adsorption heat pump performance. Based on computer simulation results, the values of the coefficients of performance for heating and cooling are calculated. The results show that adsorption heat pumps have relatively low efficiency compared to other heat pumps. The value of the coefficient of performance for heating is higher than for cooling