Assessing the effect of grain-scale sorption rate limitations on the fate of hydrophobic organic groundwater pollutants

2012 ◽  
Vol 129-130 ◽  
pp. 70-79 ◽  
Author(s):  
David Werner ◽  
Hrissi K. Karapanagioti ◽  
David A. Sabatini
Keyword(s):  
Sorption Rate ◽  
Groundwater Pollutants

Investigation of Oxygen Sorption Rate by Self-Igniting Sulfide Ores

2020 ◽  
pp. 57-62
Author(s):  
V.A. Portola ◽  
◽  
A.A. Bobrovnikova ◽  
D.Yu. Paleev ◽  
A.A. Eremenko ◽  
...  
Keyword(s):  
Sulfide Ores ◽  
Sorption Rate ◽  
Oxygen Sorption

DRIED MILK POWDER: II. FACTORS AFFECTING THE SORPTION OF CARBON DIOXIDE

1945 ◽  
Vol 23f (6) ◽  
pp. 327-333 ◽  
Author(s):  
Jesse A. Pearce
Keyword(s):  
Carbon Dioxide ◽  
Milk Powder ◽  
Sorption Rate ◽  
High Fat ◽  
Time Intervals ◽  
Sorption Behaviour ◽  
Factors Affecting ◽  
Whole Milk ◽  
Identical Manner ◽  
Whole Milk Powder

Sorption of carbon dioxide by milk powder in a closed system at 35 °C. and at approximately 74 cm. of mercury was observed to be greater than 0.4 cc. per gm. after 150 hr., while only 0.012 cc. of nitrogen was absorbed per gm. after 70 hr. The initial sorption of carbon dioxide varied with time according to the equation:[Formula: see text]where s is 100 times the amount sorbed in cc. per gm. at any time, t (min.), and k and m are constants peculiar to the system under investigation. The logarithmic form of this equation was used. Powders with 26, 28, and 30% fat did not differ in behaviour, but sorption curves for powders with only 1% fat had lower [Formula: see text] values and lower [Formula: see text] values than the curves for the high fat levels. Powders with 1% fat sorbed carbon dioxide in an identical manner when exposed to either 100% carbon dioxide or a mixture of 20% carbon dioxide and 80% nitrogen. For whole milk powder, dilution to 80% nitrogen content was effective in reducing the initial sorption rate of carbon dioxide. Great variation was observed in the sorption behaviour of powders from different plants and in powders produced at different time intervals in the same plant. Temperature differences within the range 25° to 40 °C. had no effect on sorption. Palatability and [Formula: see text] correlated to the extent of r =.61.

Adsorption of Groundwater Pollutants by Iron Nanomaterials

2018 ◽  
pp. 37-63
Author(s):  
Dimitris Dermatas ◽  
Thanasis Mpouras ◽  
Nymphodora Papassiopi ◽  
Christiana Mystrioti ◽  
Aikaterini Toli ◽  
...  
Keyword(s):  
Groundwater Pollutants

Comparison of the Efficacy and Phytotoxicity of Phosphine and Ethyl Formate for Controlling Pseudococcus longispinus (Hemiptera: Pseudococcidae) and Pseudococcus orchidicola on Imported Foliage Nursery Plants

2019 ◽  
Vol 112 (5) ◽  
pp. 2149-2156 ◽  
Author(s):  
Yejin Kyung ◽  
Hyun Kyung Kim ◽  
Sung Woo Cho ◽  
Bong-Su Kim ◽  
Jeong-Oh Yang ◽  
...  
Keyword(s):  
Plant Species ◽  
Methyl Bromide ◽  
Reduction Rate ◽  
Ethyl Formate ◽  
Sorption Rate ◽  
Pseudococcus Longispinus ◽  
High Sorption ◽  
Fumigation Chamber ◽  
Nursery Plant ◽  
Schefflera Arboricola

Abstract The fumigation activity of phosphine (PH3) and ethyl formate (EF) and their phytotoxicity to 13 imported foliage nursery plant species were evaluated. The lethal concentration and time (LCT99) values of the PH3 indicated that the susceptibility of the nymphs (3.95 and <0.45 mg·h/liter, respectively) was higher than that of the adults (5.29 and 3.66 mg·h/liter, respectively) of two mealybugs [Pseudococcus longispinus (Targioni-Tozzetti) and P. orchidicola Takahashi]. The highest concentration reduction rate of PH3 and EF on the 13 foliage nursery plants in the 12-liter desiccator was 41.5% for Heteropanax fragrans and 71.7% for Schefflera arboricola, respectively, which indicates that PH3 has a lower sorption rate than EF. The phytotoxicities of PH3-treated foliage nursery plants did not significantly differ from those of the nontreated plants, but EF caused phytotoxicity in 11 foliage nursery plants a week after treatment. When the exposure time of PH3 increased to 24 h, the adults and nymphs of both mealybug species showed 100% mortality in the 0.5 m3 fumigation chamber. In the 10 m3 fumigation container used in the field, there was 100% mortality of both mealybugs after treatment with 2 g/m3 PH3 for 24 h at 16°C. These results indicate that EF is not a suitable mealybug fumigant due to its high sorption and phytotoxicity to foliage nursery plants, despite fumigation activity against the two species. However, PH3 seems to be suitable for mealybug fumigation in foliage nursery plants and can be used as a substitute for methyl bromide.

An Experimental Investigation of Sorption Process in Fluidized Bed With Cooling Pipe

2008 ◽  
Vol 130 (11) ◽  
Author(s):  
Akihiko Horibe ◽  
Syahrul Husain ◽  
Hideo Inaba ◽  
Naoto Haruki ◽  
Ping Tu
Keyword(s):  
Experimental Investigation ◽  
Fluidized Bed ◽  
Air Conditioning ◽  
Sorption Process ◽  
Sorption Rate ◽  
Mass Ratio ◽  
Air Conditioning System ◽  
Cooling Pipe ◽  
Powder Type ◽  
Cooling Pipes

An experimental investigation of a fluidized bed with multiple cooling pipes was conducted to study adsorption characteristics of a new organic sorbent desiccant material (HU300P) for a new air conditioning system. The mass ratio of the present sorbent desiccant powder type is from 1.3 to 2.3 times greater than that of silica gel. The sorption rate of the water vapor in the sorbent bed was measured under various conditions. It was found that the sorption rate is highly dependent on the effect of cooling pipes. The sorption ratio increases and the completion time for the sorption process decreases by using multiple cooling pipes.

scholarly journals Extended Rate Constants Distribution (RCD) Model for Sorption in Heterogeneous Systems: 2. Importance of Diffusion Limitations for Sorption Kinetics on Cryogels in Batch

Gels ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 15 ◽  
Author(s):  
Irina Malakhova ◽  
Alexey Golikov ◽  
Yuliya Azarova ◽  
Svetlana Bratskaya
Keyword(s):  
Kinetic Parameters ◽  
Diffusion Model ◽  
Residence Time ◽  
Rate Constants ◽  
Heterogeneous Systems ◽  
Sorption Kinetics ◽  
Sorption Rate ◽  
Kinetic Curves ◽  
Dynamic Conditions ◽  
Diffusion Limitations

Here we address the problem of what we can expect from investigations of sorption kinetics on cryogel beads in batch. Does macroporosity of beads indeed help eliminate diffusion limitations under static sorption conditions? Are sorption rate constants calculated using phenomenological kinetic models helpful for predicting sorption properties under dynamic conditions? Applying the rate constants distribution (RCD) model to kinetic curves of Cu(II) ions sorption on polyethyleneimine (PEI) cryogel and gel beads and fines, we have shown that diffusion limitations in highly swollen beads are very important and result in at least ten-fold underestimation of the sorption rate constants. To account for intraparticle diffusion, we have developed the RCD-diffusion model, which yields “intrinsic” kinetic parameters for the sorbents, even if diffusion limitations were important in kinetic experiments. We have shown that introduction of a new variable—characteristic diffusion time—to the RCD model significantly improved the reliability of sorption kinetic parameters and allowed prediction of the minimal residence time in column required for efficient uptake of the adsorbate under dynamic conditions. The minimal residence time determined from kinetic curves simulated using the RCD-diffusion model was in good agreement with experimental data on breakthrough curves of Cu(II) ion sorption on monolith PEI cryogel at different flow rates.

Numerical Simulation of Heat and Mass Transfer in Metal Hydride Hydrogen Accumulators of Different Complex Designs

2010 ◽  
Author(s):  
Dmitriy Lazarev ◽  
Valeriy Artemov ◽  
Georgiy Yankov ◽  
Konstantin Minko
Keyword(s):  
Thermal Conductivity ◽  
Mass Transfer ◽  
Effective Thermal Conductivity ◽  
Heat And Mass Transfer ◽  
Metal Hydride ◽  
Solid Phase ◽  
Three Dimensional ◽  
Calculated Data ◽  
Sorption Rate ◽  
Gas Admixtures

A three-dimensional mathematical model of unsteady heat and mass transfer in porous hydrogen-absorbing media, accounting for presence of “passive” gas admixtures, is developed. New technique for evaluation of effective thermal conductivity of porous medium, which consists of microparticles, is suggested. Effect of “passive” gas admixtures on heat and mass transfer and sorption rate in metal hydride reactor is analyzed. It is shown that decrease of effective thermal conductivity and partial hydrogen pressure under decrease of hydrogen concentration effect on the hydrogen sorption rate considerably. It is disclosed that an intensive 3D natural convection takes place in a gas volume of reactor under certain conditions. Numerical analysis of heat and mass transfer in metal-hydride reactor of hydrogen accumulation systems was done. Sorption of hydrogen in cylindrical reactors with external cooling and central supply of hydrogen are analyzed including reactors with finned active volume and tube-shell reactor with external and internal cooling cartridge matrix. Unsteady three dimensional temperature and concentration fields in solid phase are presented. Integral curves representing the dynamic of sorption and desorption are calculated. Data on efficiency of considered reactors are presented and compared.

Sign in / Sign up

Export Citation Format

Share Document