Kinetics for ammonium ion removal using a three-dimensional electrode system

2013 ◽  
Vol 67 (1) ◽  
pp. 168-173 ◽  
Author(s):  
Qicheng Qiao ◽  
Yuemin Zhao ◽  
Lizhang Wang

Electrochemical oxidation of ammonium ions (NH4+) by using a three-dimensional electrode (TDE) composed of IrO2–Ta2O5/Ti anode and bamboo carbon was carried out in this paper. Experimental results reveal that the NH4+ oxidation follows first-order kinetics at lower NH4+ concentration and the rate constant is highly dependent on the applied current density, dosage of chlorine ions and initial NH4+ concentration. In addition, increasing current density, more Cl− dosage and higher initial NH4+ concentration are beneficial for NH4+ removal. By inspecting the relation between rate constant and those operating factors, an overall empirical equation for estimation of the rate constant of NH4+ oxidation is presented. The estimated model is in good agreement with the experimental results and it could also be used for accurate design of the TDE system.

2011 ◽  
Vol 63 (11) ◽  
pp. 2732-2736 ◽  
Author(s):  
Xu-wen He ◽  
Li-yuan Liu ◽  
Hao Wang ◽  
Gong Zhang ◽  
Jing-wen Gong ◽  
...  

The electrochemical oxidation of the residual ammonia nitrogen contained in biologically pretreated coking wastewater using three-dimensional electrode system was studied. The results show the Ti/RuO2/IrO2 anode plates and the coke have good surface characteristics for the purpose of this study. In addition, studies also show that the three-dimensional electrode system should be able to give a satisfied solution to the residual bio-refractory ammonia nitrogen in biologically pretreated coking wastewater in comparison to conventional two-dimensional electrodes. At coke size of 10–20 mesh, electrode distance of 1.0 cm and current density of 4.5 mA/cm2, the residual ammonia nitrogen in the three-dimensional electrode system was almost completely removed in 60 min.


2013 ◽  
Vol 690-693 ◽  
pp. 1065-1068 ◽  
Author(s):  
Zhen Wang ◽  
Ze Sheng Cheng ◽  
Yu Liu ◽  
Na Na Bo ◽  
Ying Liu

Tertiary treatment wascarried out to treat pulp and paper effluent from secondary treatment processby a three-dimensional electrode system equipped with modifiedbentonites as powdery electrode. The cetyl trimethylammonium bromide modified bentonite (CTAB-bent) and hydroxy-aluminum pillaredorganic bentonite (OH-Al-CTAB-bent) were synthesized and characterized by XRDand FTIR spectroscopy analysis.The impacts such as the dosage of particle electrode, electrolysis times,current density were on the COD removal efficiency and decolorization effect ofeffluent were also investigated. The results showed that the experimentscarried out by three-dimensional electrode system with OH-Al-CTAB-bent weresufficient for the COD and color removal efficiency. A current density of 30mA/cm2, electrolysis time of 40min, and the particle electrodedosage of 1.6g/L were selected as an optimum conditions that allows fast andlow cost treatment. The effluent can achieve the discharge standard of waterpollutants for pulp and paper industry (GB3544-2008) after electrolysis.


2020 ◽  
Vol 14 (2) ◽  
pp. 88
Author(s):  
Emad Yousif

This article focus on the calculation of photodecomposition rate constant of PVC films that containing sulfadiazine tin(IV) complexes 1-3 as photostabilzers during UV radiation exposure. This constant calculated as a method for evaluating the efficiency of sulfadiazine tin(IV) complexes 1-3 when used as a PVC photostabilizers after 300 hours of irradiation. The experimental results showed that sulfadiazine tin(IV) complexes 1-3 have reduced the rate of photodecomposition constant value of PVC films significantly with comparison to PVC (blank).


Author(s):  
Yingchun Zhang ◽  
Changsheng Cao ◽  
Xintao Wu ◽  
Qi-Long Zhu

Bismuth (Bi)-based nanomaterials are considered as the promising electrocatalysts for electrocatalytic CO2 reduction reaction (CO2RR), but it is challenging to achieve high current density and selectivity in a wide potential...


Author(s):  
Poonam Rani ◽  
MPS Bhatia ◽  
Devendra K Tayal

The paper presents an intelligent approach for the comparison of social networks through a cone model by using the fuzzy k-medoids clustering method. It makes use of a geometrical three-dimensional conical model, which astutely represents the user experience views. It uses both the static as well as the dynamic parameters of social networks. In this, we propose an algorithm that investigates which social network is more fruitful. For the experimental results, the proposed work is employed on the data collected from students from different universities through the Google forms, where students are required to rate their experience of using different social networks on different scales.


2014 ◽  
Vol 687-691 ◽  
pp. 3-6
Author(s):  
Da Ming Wang ◽  
Ming Zhe Li ◽  
Zhong Yi Cai

3D rolling is a novel technology for three-dimensional surface parts. In this process, by controlling the gap between the upper and lower forming rolls, the sheet metal is non-uniformly thinned in thickness direction, and the longitudinal elongation of the sheet metal is different along the transverse direction, which makes the sheet metal generate three-dimensional deformation. In this paper, the transition zones of spherical surface parts in 3D rolling process are investigated. Spherical surface parts with the same widths but different lengths are simulated in condition of the same roll gap, and their experimental results are presented. The forming precision of forming parts and the causes of transition zones in the head and tail regions are analyzed through simulated results. The simulated and experimental results show that the lengths of transition zones of spherical surfaces in the head and tail regions are fixed values in condition of the same sheet width and roll gap.


2006 ◽  
Vol 71 (3) ◽  
pp. 411-422 ◽  
Author(s):  
David Havlíček ◽  
Libor Turek ◽  
Jiří Plocek ◽  
Zdeněk Mička

Solubility in the (Me4N)2SeO4-H2SeO4-H2O and (Me4N)2SeO4-Li2SeO4-H2O systems were studied. The new compounds, tetramethylammonium hydrogenselenate monohydrate ((Me4N)HSeO4·H2O) and lithium tetramethylammonium selenate tetrahydrate (Li(Me4N)SeO4·4H2O), have been found in these systems. Both substances were characterised by chemical analysis and IR molecular spectroscopy. Both of the title substances decompose under the influence of X-radiation and, thus, their structures cannot be determined. The radiolysis of both substances was studied in greater detail. Tetramethylammonium hydrogenselenate monohydrate is dehydrated by X-radiation to form the anhydrous salt. The reaction is controlled by first-order kinetics with a rate constant of 1.30(3) × 10-3 s-1.


2013 ◽  
Vol 333-335 ◽  
pp. 1145-1150 ◽  
Author(s):  
Gao Yuan Dai ◽  
Zhi Cheng Li ◽  
Jia Gu ◽  
Lei Wang ◽  
Xing Min Li ◽  
...  

This paper proposes a fast GrowCut (FGC) algorithm and applies the new algorithm in three-dimensional (3D)kidney segmentation from computed tomography (CT) volume data. Users could mark the object of interest with different labels in CT slices.FGC propagates the labels using monotonically decreasing function and color features to derive an optimal cut for a given data in space. The color features play a great role in comparing with neighborhood cells. The experimental results clearly demonstrate the superiority of FGC in accuracy and speed.


Author(s):  
Demeng Che ◽  
Jacob Smith ◽  
Kornel F. Ehmann

The unceasing improvements of polycrystalline diamond compact (PDC) cutters have pushed the limits of tool life and cutting efficiency in the oil and gas drilling industry. However, the still limited understanding of the cutting mechanics involved in rock cutting/drilling processes leads to unsatisfactory performance in the drilling of hard/abrasive rock formations. The Finite Element Method (FEM) holds the promise to advance the in-depth understanding of the interactions between rock and cutters. This paper presents a finite element (FE) model of three-dimensional face turning of rock representing one of the most frequent testing methods in the PDC cutter industry. The pressure-dependent Drucker-Prager plastic model with a plastic damage law was utilized to describe the elastic-plastic failure behavior of rock. A newly developed face turning testbed was introduced and utilized to provide experimental results for the calibration and validation of the formulated FE model. Force responses were compared between simulations and experiments. The relationship between process parameters and force responses and the mechanics of the process were discussed and a close correlation between numerical and experimental results was shown.


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