The Influence of Particle Size and Calcium Content on Performance Characteristics of Metakaolin- and Fly-Ash-Based Geopolymer Gels.

This research systematically investigates the influence of raw material particle size and calcium content on the geopolymerization process to gain insight into the physical and mechanical properties of geopolymer gels, including setting time, fluidity, pore structure, compressive strength, and leaching characteristics of encapsulated Cr heavy metal ions. Utilizing a diverse range of particle sizes of metakaolin (MK; 3.75, 7.

Predictive modeling of pH on the transport of Co(II) Ions from aqueous solutions through supported ceramic polymer membrane.

Optimal pH is essential for efficient cobalt extraction from polymeric membrane systems, with DEHPA used as an extractant for Co(II) at pH < 7, achieving 47% efficiency. The pH of piperazine as a stripping agent increases to a concentration of 0.48 M, and the extraction efficiency of Co(II) > 80%.

Efficient uptake of Sr and Co using fabricated inorganic sorbent for reducing radiation doses of simulated low-level waste.

The present study investigated the sorption behavior of Sr and Co radionuclides from aqueous solutions onto tin molybdate (SnMo) sorbent. SnMo has been synthesized using the precipitation method and was characterized using four analytical techniques including FT-IR, XRD, SEM, and XRF. The sorption studies applied on Sr and Co include the effect of shaking time, pH, concentration, and saturation capacity.

Modeling of liquid-liquid hollow fiber supported membrane equilibrium including the non-ideality of the aqueous and organic phases in the recovery systems of radionuclides in sulphate-halide/aliquat-336 in O-xylene.

Study of modeling of L/LHFSLM equilibrium based on the Non-ideality of the Aqueous and Organic Phases in the Recovery of Eu in HSO-Halides/Aliquat-336 in 20% kerosene as feeding phase at pH 3.78-4.55, by the ratio 89.

Utilization of carbon-coated ZrO/Mn-Mg-Zn ferrites nanostructures for the adsorption of Cs (I) and Sr (II) from the binary system: kinetic and equilibrium studies.

Carbon-coated ZrO/Mn-Mg-Zn ferrites nanostructures (CZ-FN) have been prepared as a new inorganic sorbent to remove Cs (I) and Sr (II) from a waste stream. Adsorption of Cs (I) and Sr (II) has been implemented considering different noteworthy parameters, for example, shaking time and the optimum time achieved high adsorption capacity of both ions [103 and 41 mg/g for Sr (II) and Cs (I)] was found 30 min. Also, the impact of pH values was studied; the best pH value for the adsorption process is pH 6.

Fabrication of magnesium oxide-calcium alginate hydrogel for scaffolding yttrium and neodymium from aqueous solutions.

In this research, the possibility of using sustainable nano-MgO/Ca-alginate beads for efficient sorption of some rare earth metal ions such as neodymium(III) and yttrium(III) from an aqueous acidic solution was explored. The nano-MgO/Ca-alginate beads adsorbent was characterized before and after sorption of Nd(III) and Y(III) using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), energy dispersive X-ray analysis (EDX), and X-ray diffraction (XRD) techniques. Batch sorption parameters were investigated, such as contact time, initial metal ion concentration, and adsorbent dose (V/m).

Chemically Activated Carbon Based on Biomass for Adsorption of Fe(III) and Mn(II) Ions from Aqueous Solution.

Rice husk was converted into activated carbon (AC) as a byproduct of agricultural waste in an electric furnace at 700 °C and chemically activated using three distinct processes: NaOH AC(C), acetic acid AC(C-1), phosphoric acid AC(C-2), and carbonization AC(C-3) without any chemical activation. To characterize the activated carbon and the removal efficiencies of Fe(III) and Mn(II) from aqueous solutions, various analytical tools were used. The results revealed that the capacities of the four adsorbents to adsorb Fe(III) or Mn(II) from an aqueous solution differ significantly.

Bentonite phosphate modified with nickel: Preparation, characterization, and application in the removal of Cs and Eu.

The present study concerns the sorption of Cs and Eu from low-level radioactive waste (LLW) by bentonite phosphate modified with nickel (BPN) sorbent material. BPN was synthesized using the precipitation method and characterized using various analytical techniques such as Fourier transform infrared (FT-IR), scanning electron microscope (SEM), X-ray fluorescence (XRF), and X-ray diffraction (XRD). The sorption data show that 90 min is enough time to reach equilibrium.

Removal of Cs and Sr from simulated low-level radioactive waste using tin(IV) vanadate sorbent and its potential hazardous parameters.

This study is concerned with the sorption of Cs and/or Sr from low-level radioactive waste using tin(IV) vanadate (SnV) sorbent fabricated by the precipitation technique. The structure and properties of SnV were studied using different analytical tools such as X-ray diffraction, X-ray fluorescence, Fourier-transform infrared, and scanning electron microscopy. Batch technique was used to investigate the sorption behavior of SnV towards Cs and/or Sr considering the influence of independent parameters including pH of the solution, contact time, and initial metal ions concentrations in simulation studies using the γ emitting isotopes Cs and Sr as representatives of Cs and Sr, respectively.

Ni-alginate hydrogel beads for establishing breakthrough curves of lead ions removal from aqueous solutions.

The scientific impact of this work is the protection of the environment from hazardous pollutants using a column technique. Besides its higher stability at working pH and its time persisting, Ni-alginate has a higher ability to remove lead ions compared to the other prepared beads (Sr-alginate, Co-alginate, and Ca-alginate). Also, Ni-alginate possessed a higher removal percent, 93.

High efficient removal of lead(II) and cadmium(II) ions from multi-component aqueous solutions using polyacrylic acid acrylonitrile talc nanocomposite.

This study is interested in the removal of Pb(II), Cd(II), Co(II), Zn(II), and Sr(II) onto polyacrylic acid acrylonitrile talc P(AA-AN)-talc nanocomposite. P(AA-AN)-talc was fabricated using γ-irradiation-initiated polymerization at 50 kGy. Different analytical tools were used to investigate the functional groups, morphology, particle size, and structure of this composite.

NanoTafla Nanocomposite as a Novel Low-Cost and Eco-Friendly Sorbent for Strontium and Europium Ions.

Now the wide use of nanooxides is attributed to their remarkable collection of properties. Nanocomposites have an impressive variety of important applications. A thermal decomposition approach provides a more optimistic method for nanocrystal synthesis due to the low cost, high efficiency, and expectations for large-scale production.

Sorbent extraction behavior of cesium and strontium from nitric acid solutions using a new high thermal stability material.

In this study a new low-cost carbonaceous material was prepared from husks of opuntia-ficus-indica as a starting material (precursor) which was accomplished by chemical activation route using HPO impregnation. The material has been identified by different analytical tools. The sorption performance of Cs(I) and Sr(II) from HNO solutions was examined through batch system.

Sorption of some radionuclides from liquid waste solutions using anionic clay hydrotalcite sorbent.

I and Se are potentially important anionic radionuclides in safety assessments due to their high mobility, radiotoxicity, and long half life's (1.7 × 10 and 3.27 × 10 years, respectively).

Gamma radiation-induced polymerization of polyacrylic acid-dolomite composite and applications for removal of cesium, cobalt, and zirconium from aqueous solutions.

Gamma-irradiation initiated polymerization was utilized to prepare polyacrylic acid dolomite P(AA/D) nanocomposites. Different analytical techniques have been applied to investigate the structure of the new materials. XRD and TEM revealed the crystalline phase with an average particle size ranging from 2 to 4 nm.

Purification of rad-waste arising from irradiated natural tin target towards tellurium-125m/antimony-125 radioisotope generator elaboration.

The present study introduces a new approach based on an irradiated tin target's impurity to produce aSb/Te radioisotope generator. A prepared generator gel matrix of zirconium-silico-tungstate was loaded with 6660 MBq (180 mCi) activity of the separated antimony. The loading and elution method has been studied as a function of the concentration of HSO acid solution.

Performance characteristics and validation of alpha particle spectrometers for radiometric analysis of natural and anthropogenic radionuclides of environmental impacts.

Alpha spectrometry is one of the greatest nuclear techniques for identification and quantification of α-emitters in the environment due to nuclear fuel cycle operations, nuclear materials and geochemical studies or forensic medicine investigations. This study was conducted to re-evaluate and optimize the factors affecting the performance of a multi-chamber alpha spectrometer (EG&G Ortec) used in our laboratory using an aged α-source of U in equilibrium with its decay products. The results shown that the energy calibration within energy window 4-9 MeV has been done using alpha particle emissions of U (t.

Exploration of the parameters affecting the radioactive europium removal from aqueous solutions by activated carbon-epoxy composite.

Adsorption of radioactive europium from aqueous solution was achieved using activated carbon - epoxy composite. The preparation of activated carbon - epoxy composite was reported using gamma radiation. The ratio of the activated carbon: epoxy was 50:50 Wt %.

Removal of strontium radionuclides from liquid scintillation waste and environmental water samples.

Strontium-90 (t = 29 y) is one of the most concerned isotopes in both nuclear accidents and reprocessing of nuclear fuel. In this study, the removal of strontium using low cost and valuable Dowex-HCR-S/S (DHS) resin was achieved. The kinetic and equilibrium sorption studies have been investigated using batch technique.

Kinetics and mechanism of radium-isotopes dissolution in TENORM scale waste associated with petroleum production using certain organic carbon source: lactic acid solution-case study.

The present study is conducted to explore the dissolution as inferred from the kinetic mechanism for radium-isotopes (Ra, Ra, and Ra) in the TENORM scale waste deposited in oilfield pipes and equipment, Gulf of Suez, Egypt. The main efficiency factors for Ra-compound dissolution by lactic acid (LA) solution, e.g.

Porous carbon supported calcium oxide for CO adsorption and separation of CO/CH.

Calcium oxide incorporated porous carbon materials were synthesized by the impregnation method to study CO adsorption and separation of CO/CH. The X-ray diffraction, Raman analysis, N isotherms at 77 K, and SEM with EDX analysis were used to characterize synthesized materials. XRD and N isotherm results have confirmed that synthesized carbon has porosity, and EDX analysis has reported that the presence of CaO on porous carbon.

Sorption of some radionuclides from nuclear waste effluents by polyaniline/SiO composite: Characterization, thermal stability, and gamma irradiation studies.

Polyaniline/SiO composite was successfully prepared via in situ polymerization using polyvinyl alcohol as a surfactant. The prepared PAn/SiO composite was used for the removal of Zr(IV), U(VI), and Mo(VI) ions from their liquid solutions. PAn/SiO composite was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA).

Development of new organic-inorganic, hybrid bionanocomposite from cellulose and clay for enhanced removal of Drimarine Yellow HF-3GL dye.

Cellulose/clay composites were prepared and applied for the adsorption of Drimarine Yellow HF-3GL direct dye. The prepared composites were characterized by FTIR, TGA, EDX, SEM and XRD techniques. Bagasse was used as a cellulose source, while clay was obtained from local source, which was modified chemically before composite preparation.