Uptake Rate of Hydrogen Getter for Effectively Removing Outgassed H2 from Microelectronic Packages

2020 ◽  
Vol 2020 (1) ◽  
pp. 000298-000301
Author(s):  
Hua Xia ◽  
Jeffrey Vriens ◽  
David DeWire

Abstract Hydrogen absorption kinetic properties of palladium foil-based getter elements have been studied by manometric method based pressure amplitude measurement. The getter H2 uptake rate can be simply converted by pressure amplitude change, and can be fairly described by a mixed gas sorption modeling analysis. It has been found that the sorption rate of Pd-based getter element has a maximum rate of 40 ppm/min at initial absorption stage but it gets slowly down to 0.5ppm/min when approaching maximum sorption capacity, determined by a getter foil thickness. Based on different H2 outgassing rates of metal and polymer based package materials, a safety factor based methodology has been proposed for down selecting an appropriate getter element that can effectively removing outgassed H2 from microelectronic packages.

Author(s):  
A. Safonov ◽  
N. Andriushchenko ◽  
N. Popova ◽  
K. Boldyrev

Проведен анализ сорбционных характеристик природных материалов (вермикулит, керамзит, перлит, цеолит Трейд ) при очистке кадмий- и хромсодержащих сточных вод с высокой нагрузкой по ХПК. Установлено, что цеолит обладает максимальными сорбционными характеристиками для Cd и Cr и наименьшим биологическим обрастанием. При использовании вермикулита и керамзита или смесей на их основе можно ожидать увеличения сорбционной емкости для Cd и Сr при микробном обрастании, неизбежно происходящем в условиях контакта с водами, загрязненными органическими соединениями и биогенами. При этом биообрастание может повысить иммобилизационную способность материалов для редоксзависимых металлов за счет ферментативных ресурсов бактериальных клеток, использующих их в качестве акцепторов электронов. Эффект микробного обрастания разнонаправленно изменял параметры материалов: для Cr в большинстве случаев уменьшение и для Cd значительное увеличение. При этом дополнительным эффектом иммобилизации Cr является его биологическое восстановление биопленками. Варьируя состав сорбционного материала, можно подбирать смеси, оптимально подходящие для очистки вод инфильтратов с полигонов твердых бытовых отходов с высокой нагрузкой по ХПК и биогенным элементам как при использовании in situ, так и в системах на поверхности.The analysis of the sorption characteristics of natural materials (vermiculite, expanded clay, perlite, Trade zeolite) during the purification of cadmium and chromium-containing leachate with a high COD load was carried out. It was determined that zeolite had the maximum sorption capacity for Cd and Cr and the lowest biological fouling. When using vermiculite and expanded clay or mixtures on their basis, one can expect an increase in the sorption capacity for Cd and Cr during microbial fouling that inevitably occurs during contacting with water polluted with organic compounds and nutrients. In this case biofouling can increase the immobilization properties of materials for redox-dependent metals due to the enzymatic resources of bacterial cells that use them as electron acceptors. The effect of microbial fouling changed the parameters of materials in different directions: for Cr, in most cases, downward, and for Cd, significantly upward. Moreover, chromium biological recovery by biofilms is an additional effect of immobilization. Varying the composition of the sorption material provides for selecting mixtures that are optimally suitable for the purification of leachates from solid waste landfills with high COD and nutrients load, both when used in situ and in surface systems.


2021 ◽  
Vol 13 (3) ◽  
pp. 1502
Author(s):  
Maria Xanthopoulou ◽  
Dimitrios Giliopoulos ◽  
Nikolaos Tzollas ◽  
Konstantinos S. Triantafyllidis ◽  
Margaritis Kostoglou ◽  
...  

In water and wastewater, phosphate anions are considered critical contaminants because they cause algae blooms and eutrophication. The present work aims at studying the removal of phosphate anions from aqueous solutions using silica particles functionalized with polyethylenimine. The parameters affecting the adsorption process such as pH, initial concentration, adsorbent dose, and the presence of competitive anions, such as carbonate, nitrate, sulfate and chromate ions, were studied. Equilibrium studies were carried out to determine their sorption capacity and the rate of phosphate ions uptake. The adsorption isotherm data fitted well with the Langmuir and Sips model. The maximum sorption capacity was 41.1 mg/g at pH 5, which decreased slightly at pH 7. The efficiency of phosphate removal adsorption increased at lower pH values and by increasing the adsorbent dose. The maximum phosphate removal was 80% for pH 5 and decreased to 75% for pH 6, to 73% for pH 7 and to 70% for pH 8, for initial phosphate concentration at about 1 mg/L and for a dose of adsorbent 100 mg/L. The removal rate was increased with the increase of the adsorbent dose. For example, for initial phosphate concentration of 4 mg/L the removal rate increased from 40% to 80% by increasing the dose from 0.1 to 2.0 g/L at pH 7. The competitive anions adversely affected phosphate removal. Though they were also found to be removed to a certain extent. Their co-removal provided an adsorbent which might be very useful for treating waters with low-level multiple contaminant occurrence in natural or engineered aquatic systems.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3541
Author(s):  
Ion Ion ◽  
Daniela Bogdan ◽  
Monica Maria Mincu ◽  
Alina Catrinel Ion

In this manuscript an improved sorbent based on modified exfoliated carbon nanoplatelets, applied in the removal of ammonium from aqueous samples, is presented. This sorbent showed better efficiency in comparison with the previous one obtained in our group for ammonium removal, the values of the maximum sorption capacity being improved from 10 to 12.04 mg/g. In terms of kinetics and sorption characteristic parameters, their values were also improved. Based on these results, a sorption mechanism was proposed, taking into account ion-exchange and chemisorption processes at the surface of the oxidized exfoliated carbon nanoplatelets. Future applications for simultaneous removal of other positive charged contaminants from natural waters might be possible.


2011 ◽  
Vol 356-360 ◽  
pp. 537-546
Author(s):  
Yow Loo Au Yoong ◽  
Pei Lay Yap ◽  
Muralithran G. Kutty ◽  
Olaf Timpe ◽  
Malte Behrens ◽  
...  

The use of surface oxidized covellite (CuS), namely mixed phase copper sulphide (CuS and CuSO4) was studied for the removal of mercury from aqueous solution under the effect of various reaction parameters (pH, time, Hg(II) concentration). From batch sorption studies, the equilibrium data revealed that the sorption behaviour of Hg(II) onto mixed phase copper sulphide follows well with Langmuir isotherm and the maximum sorption capacity (Qmax) determined ≈ 400mg Hg(II) /g of sorbent. Meanwhile, all the unreacted and reacted mixed phase copper sulphides were also characterized by Powder XRD, SEM and XPS techniques. The results indicated that the sorption of Hg(II) onto mixed phase copper sulphide occurs initially through the dissolution of surface oxidized CuSO4layer. After that, the surface complexation product formed and sorbed onto the surface of CuS. These outcomes suggest the potential ability of CuS in removing Hg(II) even if the CuS layer is being surrounded by oxidized layer of CuSO4.


Soil Research ◽  
2007 ◽  
Vol 45 (8) ◽  
pp. 618 ◽  
Author(s):  
Wanting Ling ◽  
Qing Shen ◽  
Yanzheng Gao ◽  
Xiaohong Gu ◽  
Zhipeng Yang

A decrease in release and availability of heavy metals in soil has been of worldwide interest in recent years. Bentonite is a type of expandable montmorillonite clay, and has strong sorption for heavy metals. In this work, the control of amended bentonite on the release of copper (Cu2+) from spiked soils was investigated using a batch equilibrium technique. Sorption of Cu by bentonite was pH-dependent, and could be well described using the Langmiur model. Maximum sorption capacity of the bentonite used in this study was 5.4 mg/g, which was much greater than soils reported in the literature. The extent of Cu2+ release from spiked soils was correlated with slurry concentrations, pH, and soil ageing process. In all cases, the amendment of bentonite was observed to effectively decrease the release of Cu2+ from soils. The apparent aqueous concentrations of Cu2+ released from soils devoid of bentonite treatment were 113–1160% higher than those from the soils amended with bentonite. Moreover, the magnitude of Cu2+ release decreased with increasing amount of bentonite added to soils. The bentonite added was more effective in retaining Cu2+ in sorbents for aged contaminated soils. Such enhanced retention resulting from the presence of bentonite was observed within a wide pH range from 2.5 to 7.0. Bentonite, as one of the most abundant minerals in soils, is regarded to improve the soil overall quality. The results obtained from this work provide useful information on utilisation of bentonite to control the release of heavy metals from contaminated soils.


RSC Advances ◽  
2014 ◽  
Vol 4 (76) ◽  
pp. 40580-40587 ◽  
Author(s):  
Prasanta Kumar Raul ◽  
Samarpita Senapati ◽  
Ashish K. Sahoo ◽  
Iohborlang M. Umlong ◽  
Rashmi R. Devi ◽  
...  

CuO nanorods can remove Pb(ii) from aqueous solution with a maximum sorption capacity of 3.31 mg g−1at 298 K.


2015 ◽  
Vol 16 (1) ◽  
pp. 115-127 ◽  
Author(s):  
P. Dhanasekaran ◽  
P. M. Satya Sai ◽  
C. Anand Babu ◽  
R. Krishna Prabhu ◽  
K. K. Rajan

Arsenic is a toxic element found naturally in groundwater. Due to its carcinogenicity, risk for heart diseases and diabetes, arsenic needs to be removed from groundwater for potable application. ‘Anjili’ tree sawdust was chemically modified with ferric hydroxide and activated alumina (SFAA) and used as an adsorbent for the removal of arsenic from groundwater. The adsorbent was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) to study the pore structure and surface functional groups. Effect of contact time, initial concentration, pH, particle size and temperature was studied. Arsenic adsorbed by SFAA followed Freundlich adsorption isotherm. Maximum sorption of arsenic by SFAA adsorbent occurred at pH 6.5. Arsenic sorption kinetics followed a pseudo-second-order model. The maximum sorption capacity at 303 K was found to be 54.32 mg/g for As(III) and 77.60 mg/g for As(V). Interference of other ions on the adsorption was in the order of PO43− > SO42− > HCO3− > NO3−.


2019 ◽  
Vol 17 (3) ◽  
pp. 1211-1224 ◽  
Author(s):  
T. Jóźwiak ◽  
U. Filipkowska ◽  
S. Brym ◽  
L. Kopeć

Abstract In this study, we analyzed the effectiveness of sorption of dyes popular in the textile industry (Reactive Black 5, Reactive Yellow 84, Acid Yellow 23, and Acid Red 18) on aminated and non-aminated seed hulls of common sunflower (Helianthus annuus L.). The scope of the study included: determination of the effect of pH on dye sorption effectiveness, sorption kinetics analyses (sorption equilibrium time, pseudo-first-order/pseudo-second-order model, intramolecular diffusion model), and determination of the maximum sorption capacity against dyes (Langmuir/Freundlich isotherm). The sorbent was subjected to the FTIR analysis. The sorption capacity of the aminated sunflower seed hulls against reactive dyes RB5 and RY84 accounted for 51.02 mg/g and 63.27 mg/g, respectively, and was higher by 1665% (17.6 times higher) and 1425% (15.3 times higher) compared to that of non-modified hulls. In the case of acidic dyes, Acid Yellow 23 and Acid Red 18, the sorption capacity of the aminated sunflower seed hulls reached 44.78 mg/g and 42.19 mg/g, respectively, and was higher by 1881% (19.8 times higher) and 2284% (23.8 times higher), respectively, compared to the non-modified hulls.


Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2405
Author(s):  
Alzhan Baimenov ◽  
Dmitriy Berillo ◽  
Seitkhan Azat ◽  
Talgat Nurgozhin ◽  
Vassilis Inglezakis

In this study amphoteric cryogels were synthesized by the use of free-radical co-polymerization of acrylate-based precursors (methacrylic acid and 2-acrylamido-2-methyl-1-propansulfonic acid) with allylamine at different ratios. The physico-chemical characteristics of the cryogels were examined using SEM/EDX, FT-IR, XPS and zeta potential measurements. The cryogels were tested toward Cd2+ removal from aqueous solutions at various pH and initial concentrations. Equilibrium studies revealed a maximum sorption capacity in the range of 132–249 mg/g. Leaching experiments indicated the stability of Cd2+ in the cryogel structure. Based on kinetics, equilibrium and characterization results, possible removal mechanisms are proposed, indicating a combination of ion exchange and complexation of Cd2+ with the cryogels’ surface functional groups. The cryogels were compared to commercially available adsorbents (zeolite Y and cation exchange resin) for the removal of Cd2+ from various water matrices (ultrapure water, tap water and river water) and the results showed that, under the experimental conditions used, the cryogels can be more effective adsorbents.


Gels ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 12 ◽  
Author(s):  
Mohammed F. Hamza ◽  
Amal E. Mubark ◽  
Yuezou Wei ◽  
Thierry Vincent ◽  
Eric Guibal

The necessity to recover uranium from dilute solutions (for environmental/safety and resource management) is driving research towards developing new sorbents. This study focuses on the enhancement of U(VI) sorption properties of composite algal/Polyethylenimine beads through the quaternization of the support (by reaction with glycidyltrimethylammonium chloride). The sorbent is fully characterized by FTIR, XPS for confirming the contribution of protonated amine and quaternary ammonium groups on U(VI) binding (with possible contribution of hydroxyl and carboxyl groups, depending on the pH). The sorption properties are investigated in batch with reference to pH effect (optimum value: pH 4), uptake kinetics (equilibrium: 40 min) and sorption isotherms (maximum sorption capacity: 0.86 mmol U g−1). Metal desorption (with 0.5 M NaCl/0.5 M HCl) is highly efficient and the sorbent can be reused for five cycles with limited decrease in performance. The sorbent is successfully applied to the selective recovery of U(VI) from acidic leachate of uranium ore, after pre-treatment (cementation of copper, precipitation of rare earth elements with oxalate, and precipitation of iron). A pure yellow cake is obtained after precipitation of the eluate.


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