Adsorption Characteristics of Natural Zeolite on Ammonia Nitrogen

2012 ◽  
Vol 599 ◽  
pp. 501-504 ◽  
Author(s):  
Wei Ping Wang ◽  
Wei Wang ◽  
Ya Qun Zhou

The experiments of ammonia nitrogen adsorption isotherm and adsorption kinetics were conducted with natural zeolite, particle size of 1~1.5 mm and 2~4 mm separately. The results show that adsorption isotherm of zeolite on ammonia nitrogen accorded with Freundlich type. The maximum adsorption of crude zeolite and fine zeolite on ammonia nitrogen are 5.83 (mg /g) and 18.38 (mg /g) respectively, which indicated that absorption effect of fine zeolite is better than crude zeolite. The adsorption process of crude zeolite on ammonia nitrogen is first-order reaction with rate constant of 0.02( g•m-2•h-1).

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Qing Chen ◽  
Yuanyuan Tian ◽  
Peng Li ◽  
Changhui Yan ◽  
Yu Pang ◽  
...  

Shale gas is an effective gas resource all over the world. The evaluation of pore structure plays a critical role in exploring shale gas efficiently. Nitrogen adsorption experiment is one of the significant approaches to analyze pore size structure of shale. Shale is extremely heterogeneous due to component diversity and structure complexity. Therefore, adsorption isotherms for homogeneous adsorbents and empirical isotherms may not apply to shale. The shape of adsorption-desorption curve indicates that nitrogen adsorption on shale includes monolayer adsorption, multilayer adsorption, and capillary condensation. Usually, Langmuir isotherm is a monolayer adsorption model for ideal interfaces; BET (Brunauer, Emmett, Teller) adsorption isotherm is a multilayer adsorption model based on specific assumptions; Freundlich isotherm is an empirical equation widely applied in liquid phase adsorption. In this study, a new nitrogen adsorption isotherm is applied to simultaneously depict monolayer adsorption, multilayer adsorption, and capillary condensation, which provides more real and accurate representation of nitrogen adsorption on shale. In addition, parameters are discussed in relation to heat of adsorption which is relevant to the shape of the adsorption isotherm curve. The curve fitting results indicate that our new nitrogen adsorption isotherm can appropriately describe the whole process of nitrogen adsorption on shale.


2012 ◽  
Vol 602-604 ◽  
pp. 1211-1214
Author(s):  
Zhi Wen Luo ◽  
Zhong Chen ◽  
Su Hong Liu

Diatomite was modified by microwave treatment to increase their utilization value, using modified diatomite to treat ammonia-nitrogen wastewater. The experiment indicated that adsorption process of modification of the modified time by microwaves and microwave power is the impact of ammonia adsorption of the main factors. Through modification experiments by raising the capacity of diatomite adsorption ammonia nitrogen, adsorption of ammonia nitrogen increase over one time. Langmuir and Freundlich isotherms were used to fit and the experimental results show that the modified diatomite adsorption onto ammonia nitrogen accords with Langmuir and Freundlich isotherm. The maximum theoretical adsorption capacities are 5.81083mg/g.


2020 ◽  
Vol 1 (2) ◽  
pp. 54-62
Author(s):  
Naser Al Amery ◽  
Hussein Rasool Abid ◽  
Shaobin Wang ◽  
Shaomin Liu

In this study, two improved versions of UiO-66 were successfully synthesised. Modified UiO-66 and UiO-66-Ce were characterised to confirm the integrity of the structure, the stability of functional groups on the surface and the thermal stability. Activated samples were used for removal harmful anionic dye (methyl orange) (MO) from wastewater. Batch adsorption process was relied to investigate the competition between those MOFs for removing MO from aqueous solution. Based on the results, at a higher initial concentration, the maximum MO uptake was achieved by UiO-66-Ce which was better than modified-UiO-66. They adsorbed 71.5 and 62.5 mg g-1 respectively. Langmuir and Freundlich isotherms were employed to simulate the experimental data. In addition, Pseudo first order and Pseudo second order equations were used to describe the dynamic behaviour of MO through the adsorption process. The high adsorption capacities on these adsorbents can make them promised adsorbents in industrial areas.


2014 ◽  
Vol 511-512 ◽  
pp. 55-58
Author(s):  
Zhe Qin ◽  
Qian Wang ◽  
Zheng Liu

This paper regarded the sediments of Lake Baiyangdian as the object of study, researched and analyzed ammonia nitrogen adsorption characteristics of sediment samples. The results showed that: the sediments adsorption to ammonia nitrogen reached a state of equilibrium after 2.5h, The ammonia nitrogen adsorption rate was maximum in 0~10min. Sediment adsorption of ammonia nitrogen was higher as ammonia nitrogen liquid balance concentration increased. The adsorption isotherm curve of ammonia nitreogen can be fitted well by the Langmuir adsorption isotherm model. The total maximum adsorption quantity of ammonia nitrogen by the sediments of Lake Baiyangdian is between 54.12mg/kg to 240.12mg/kg.


2010 ◽  
Vol 129-131 ◽  
pp. 1376-1380 ◽  
Author(s):  
Ming Zhang ◽  
Zhu Ding ◽  
Peng Liu ◽  
Ming Ke Wang ◽  
Feng Xing

Phosphoaluminate cement (PAC) sets quickly and develops high early strength. As a novel cementitious material, its hydration mechanism and microstructure are more complex than ordinary cement. Based on nitrogen adsorption isotherm method, investigated characteristic of adsorption isotherm of PAC paste, adsorption loop and pore distribution at different hydration period with various W/C ratio, results show that adsorption and desorption isotherm are tight relate to pore structure and pore distribution. In addition, the study analyzed the scope of application of nitrogen adsorption isotherm method on investigating pore structure of cement paste.


1959 ◽  
Vol 37 (10) ◽  
pp. 1105-1113 ◽  
Author(s):  
J. P. Hobson

A measure of the nitrogen adsorption isotherm on pyrex (Corning 7740) at 77.4° K has been made for pressures above the adsorbed layer ranging from 10−3 to 10−9 mm Hg. Ultrahigh-vacuum techniques were used. Geometric adsorbing areas were 60 and 32 cm2. Coverages ranged approximately from 0.001 to 0.3 monolayer. Full equilibrium was probably not achieved but the data could be represented by the Dubinin–Radushkevich equation,[Formula: see text]for P/P0 from 10−6 to 10−11, where σ is the amount adsorbed.


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