Correction to: Evaluation of hydroxyapatite/poly(acrylamide-acrylic acid) for sorptive removal of strontium ions from aqueous solution.

The original publication of this paper contains a mistake.

Evaluation of hydroxyapatite/poly(acrylamide-acrylic acid) for sorptive removal of strontium ions from aqueous solution.

A composite polymer, hydroxyapatite/poly(acrylamide-acrylic acid), was synthesized by gamma-induced polymerization. The factors affecting the sorption process were evaluated. The removal increased with time and achieved equilibrium after 1 h for all initial concentration ranges (10-50 mg/L).

Facile conversion of kaolinite into clay nanotubes (KNTs) of enhanced adsorption properties for toxic heavy metals (Zn, Cd, Pb, and Cr) from water.

Kaolinite nanotubes (KNTs) were synthesized from kaolinite by ultrasonic scrolling and characterized using X-ray diffractometer, scanning and transmission electron microscopes; and FTIR-FT Raman spectrometer. The synthetic KNTs appear as multi-walled scrolls of 12 nm average pore diameter and 50-600 nm particle length; and exhibit surface area of 105 m/g. KNTs were used as adsorbents for Zn, Cd, Pb, and Cr with uptake capacities of 103 mg/g, 116 mg/g, 89 mg/g, and 91 mg/g, respectively.

Retention behavior of cesium radioisotope on poly (acrylamido-sulfonic acid) synthesized by chain polymerization.

Poly (acrylamido-sulfonic acid) polymers have been synthesized using the technique of radical chain polymerization utilizing acrylamide and ammonium persulphate. The polymerization was triggered and controlled using radiation from 1.1 μCi radium source.

Hazardous parameters associated with natural radioactivity exposure from black sand.

Black sand samples collected from Baltim beaches (Kafr El-Sheikh governorate) in Egypt on the Mediterranean Sea shore were analyzed radiometrically and evaluated using a nondestructive gamma ray spectroscopic techniques. The natural radionuclides of Ra, Th and K in the black sand samples were identified and quantified. It is found that the activity concentrations for Ra, Th and K in different eleven sites (S1S11) were found within the ranges of 28-322, 91-308 and 81-339 Bq/kg, respectively.

Baseline evaluation for natural radioactivity level and radiological hazardous parameters associated with processing of high grade monazite.

Egyptian monazite is a promising resource and investment attractive for production of valuable metals of industrial or nuclear interest such as rare earth elements (REEs), thorium (Th) and uranium (U). The study was focused to establish a baseline framework in viewpoint of radiation protection for the workers in production of REEs from high-grade monazite treated by sodium hydroxide (NaOH) solutions. Radiological hazard indices (cancer, gonadal and other risks) were evaluated, due to emissions (α-, β- and γ-radiations) of radium-isotopes (Ra, Ra, Ra) and lead (Pb).

Preparation of activated carbon from doum stone and its application on adsorption of Co and Eu: Equilibrium, kinetic and thermodynamic studies.

Removal of radionuclides from wastewater before discharging to environment is necessary for the safety of living beings. Activated carbon prepared from doum stone (DS), an agricultural waste by-product, has been used for the sorption of Co and Eu radionuclides from aqueous solutions. DS has been characterized by different analytical tools.

Chemical distribution of hazardous natural radionuclides during monazite mineral processing.

It is very important to calculate the radioactivity concentration for low-grade monazite ore (50%) and different other materials produced as results of chemical processing stages to avoid the risk to workers. Chemical processing of low-grade monazite pass through different stages, washing by hydrochloric acid and digested with sulfuric acid and influence of pH on the precipitation of rare earth elements has been studied. The radioactivity concentrations of U(Ra) and Th as well as K were calculated in crude low-grade ore and found to be 54,435 ± 3138, 442,105 ± 29,200 and 5841 ± 345 Bq/kg, respectively.

Utilization of natural hematite as reactive barrier for immobilization of radionuclides from radioactive liquid waste.

Potential utilization of hematite as a natural material for immobilization of long-lived radionuclides from radioactive liquid waste was investigated. Hematite ore has been characterized by different analytical tools such as Fourier transformer infrared (FTIR), X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal (DT) analysis, scanning electron microscopy (SEM) and BET-surface area. In this study, europium was used as REEs(III) and as a homolog of Am(III)-isotopes (such as (241)Am of 432.

Investigation of some factors affecting on release of radon-222 from phosphogypsum waste associated with phosphate ore processing.

The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5 ± 0.

Synthesis, characterization and application of titanium oxide nanocomposites for removal of radioactive cesium, cobalt and europium ions.

New nanocomposite material containing TiO2/Poly (acrylamide-styrene sodium sulfonate) [TiO2/(P (AAm-SSS)] was prepared by in-situ intercalative polymerization of poly acrylamide (PAAm) and styrene sodium sulfonate (SSS) in the presence of TiO2 nanoparticles as inorganic filler. N, N-methylene bis acrylamide (MBA) was used as a cross linker. The polymerization process was performed using γ-radiation as reaction initiator.

Removal of 226Ra and 228Ra from TENORM sludge waste using surfactants solutions.

The feasibility of using surfactants as extracting agent for the removal of radium species from TENORM sludge produced from petroleum industry is evaluated. In this investigation cationic and nonionic surfactants were used as extracting agents for the removal of radium radionuclides from the sludge waste. Two surfactants namely cetyltrimethylammonium bromide (CTAB) and Triton X-100 (TX100) were investigated as the extracting agents.

Evaluation of radiation hazard potential of TENORM waste from oil and natural gas production.

In this study, a potential radiation hazard from TENORM sludge wastes generated during exploration and extraction processes of oil and gas was evaluated. The activity concentration of natural radionuclides (238)U, (226)Ra and (232)Th were determined in TENORM sludge waste. It was found that sludge waste from oil and gas industry is one of the major sources of (226)Ra in the environment.

Treatment of industrial wastewater containing Congo Red and Naphthol Green B using low-cost adsorbent.

The present work investigates the potential use of metal hydroxides sludge (MHS) generated from hot dipping galvanizing plant for adsorption of Congo Red and Naphthol Green B dyes from aqueous solutions. Characterization of MHS included infrared and X-ray fluorescence analysis. The effect of shaking time, initial dye concentration, temperature, adsorbent dosage and pH has been investigated.

Utilization of different crown ethers impregnated polymeric resin for treatment of low level liquid radioactive waste by column chromatography.

The main goal of this study was to find a novel impregnated resin as an alternative for the conventional resin (KY-2 and AN-31) used for low and intermediate level liquid radioactive waste treatment. Novel impregnated ion exchangers namely, poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenedi-acrylamide-4,4'(5')di-t-butylbenzo 18 crown 6 [P(AM-AA-AN)-DAM/DtBB18C6], poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenediacrylamide-dibenzo 18 crown 6 [P(AM-AA-AN)-DAM/DB18C6], and poly (acrylamide-acrylic acid-acrylonitril)-N,N'-methylenediacrylamide-18 crown 6 [P(AM-AA-AN)-DAM/18C6] were prepared and their removal efficiency of some radionuclides was investigated. Preliminary batch experiments were performed in order to study the influence of the different derivatives of 18 crown 6 on the characteristic removal performance.

Sorption reaction mechanism of some hazardous radionuclides from mixed waste by impregnated crown ether onto polymeric resin.

A novel impregnated polymeric resin was practically tested as adsorbent material for removal of some hazardous radionuclides from radioactive liquid waste. The applicability for the treatment of low-level liquid radioactive waste was investigated. The material was prepared by loading 4,4'(5')di-t-butylbenzo 18 crown 6 (DtBB18C6) onto poly(acrylamide-acrylic acid-acrylonitril)-N, N'-methylenediacrylamide (P(AM-AA-AN)-DAM).

Efficient removal of cesium from low-level radioactive liquid waste using natural and impregnated zeolite minerals.

The objective of the proposed work was focused to provide promising solid-phase materials that combine relatively inexpensive and high removal capacity of some radionuclides from low-level radioactive liquid waste (LLRLW). Four various zeolite minerals including natural clinoptilolite (NaNCl), natural chabazite (NaNCh), natural mordenite (NaNM) and synthetic mordenite (NaSM) were investigated. The effective key parameters on the sorption behavior of cesium (Cs-134) were investigated using batch equilibrium technique with respect to the waste solution pH, contacting time, potassium ion concentration, waste solution volume/sorbent weight ratio and Cs ion concentration.

Characterization of phosphogypsum wastes associated with phosphoric acid and fertilizers production.

The present work is directed to characterize the phosphogypsum (PG) wastes associated with phosphoric acid produced by the wet process in industrial facility for the production of fertilizers and chemicals in Egypt. The PG waste samples were characterized in terms of spectroscopic analysis (X-ray diffraction, X-ray fluorescence, IR spectra) and radiometric analysis (gamma- and alpha-measurements). The gamma-ray measurements showed that the average activity concentrations are 140+/-12.

Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production.

This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions.

Performance characteristics of sequential separation and quantification of lead-210 and polonium-210 by ion exchange chromatography and nuclear spectrometric measurements.

A selective separation and quantitative determination procedure for 210Pb and 210Po in various environmental matrices from different sources such as IAEA-326 soil, phosphate rocks (PR), and phosphogypsum (PG) was developed. The tested samples were digested sequentially using concentrated mineral acids (HF, HNO3) by a programmable high-pressure microwave digestion system. The sample solution was loaded onto a preconditioned ion exchange column (Sr-resin) for chromatographic separation.