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, revitalize, and add value to buildings/structures through adaptive reuse and renovation. The underlying idea is to restore the identity of the city of Prishtina, which has been alienated and imposed upon for various reasons, by preserving the

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. Oron, G., DeMalach, Y., Hoffman, Z., Manor, Y. (1991): Effluent reuse by trickle irrigation. Water Science Technol. , 24 , 103–108. Manor Y. Effluent reuse by trickle

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of Lewis acids due to coordination of Lewis acids to the imine nitrogen, tedious workup and lack of reusability for the catalyst. The use of solid acid catalysts in organic transformations has attracted considerable attention because of their

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Abstract  

The effect of various temperature treatments on TL response characteristics of CaSO4: Dy has been investigated for its reusability when the phosphor has been previously irradiated to increasingly higher gamma doses. In practice, annealing at a standard temperature, namely 400 °C, usually precedes the use or reuse of the phosphor. However, the study demonstrates that the phosphor with a previous history of high accumulated doses does not completely retain its original TL response characteristics with 400 °C treatment unless the phosphor is treated at an elevated temperature, namely 650 °C.

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Abstract  

In the present study, non-conventional solid acid catalysts such as NaY, metal ion exchanged zeolite NaY (Zn2+, Fe3+, Ce3+, La3+ and Nd3+), H-mordenite, H-β and HZSM-5 were used in order to overcome the disadvantages of conventional Friedel-Crafts catalysts for the acylation of anisole with acetic anhydride. Among the various zeolites studied, the HY zeolite shows an intermediate activity. Zeolite containing transition metal ions (Zn2+ and Fe3+) are less active and zeolite NaY is nearly inactive. The catalysts exhibit the activity in the order H-β>transition metal ions (Zn2+ and Fe3+)>HY>NaY zeolite. The highest catalytic activity of H-β could be due to its larger pore size. The type of acidity and the acid strength in zeolite Y were determined by FTIR and differential scanning calorimetric (DSC) studies on the pyridine adsorbed catalysts. The correlation of catalytic activity with acidity reveals that Brönsted acid sites in zeolite promote the acylation of anisole.

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The adsorption of Eu(III) on multiwalled carbon nanotubes (MWCNTs) as a function of pH, ionic strength and solid contents are studied by batch technique. The results indicate that the adsorption of Eu(III) on MWCNTs is strongly dependent on pH values, dependent on ionic strength at low pH values and independent of ionic strength at high pH values. Strong surface complexation and ion exchange contribute to the adsorption of Eu(III) on MWCNTs at low pH values, whereas surface complexation and surface precipitation are the main adsorption mechanism of Eu(III) on MWCNTs. The desorption of adsorbed Eu(III) from MWCNTs by adding HCl is also studied and the recycling use of MWCNTs in the removal of Eu(III) is investigated after the desorption of Eu(III) at low pH values. The results indicate that adsorbed Eu(III) can be easily desorbed from MWCNTs at low pH values, and MWCNTs can be repeatedly used to remove Eu(III) from aqueous solutions. MWCNTs are suitable material in the preconcentration and solidification of radionuclides from large volumes of aqueous solutions in nuclear waste management.

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Abstract  

The Henry reaction between nitromethane and benzaldehydes, which yields (E)-nitrostyrenes, was for the first time conducted by using a commercially available sepiolite calcined at 400 °C as catalyst. The process is environmentally benign as it is performed in an aqueous medium and using a nitromethane/benzaldehydes ratio of only 3. A reaction mechanism accounting for the results is proposed.

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Abstract  

When chemical reactions are performed in semi-batch mode and the reaction rate is relatively low, the reactant added may be accumulated. The resulting thermal accumulation is of major concern regarding process safety, as a fault in the cooling system may lead to a run-away reaction. The feed rate in semi-batch processes is usually constant, but this paper discusses methods of optimizing the feed rate interactively, based on the measured heat flow and the calculated amount of compound that has actually reacted. The prerequisite of such procedures is to run the experiments in a reaction calorimeter in which the heat flows can be measured accurately and continuously. For this purpose a ChemiSens reaction calorimeter CPA202, which is calibration free and gives stable, flat ‘zero-line-type’ baselines, was employed.

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alcohols with hydrogen peroxide, such as Na 12 [WZnZn 2 (H 2 O) 2 (ZnW 9 O 34 ) 2 ] [ 13 , 14 ], Na 6 [SiW 11 ZnH 2 O 40 ]·12H 2 O [ 15 ], K 8 [BW 11 O 39 H]·13H 2 O [ 16 ] and K 8 [γ-SiW 10 O 36 ]·13H 2 O [ 17 ]. The catalysts could be reused without

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. Feweks 1999 Guidelines for greywater re-use: health issues Water and Environment Journal 13 322 – 326 . [5

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