⁹⁹Mo Sorption by Thermally Treated Hydrotalcites

Abstract

MoO4 2- ions were sorbed in calcined hydrotalcite contained in a column. It was found that 98% of 99mTc formed by 99Mo decay was eluted through the column in the form of pertechnetate. The content of radionuclides was determined by γ-spectrometry, and natural molybdenum was measured by neutron activation analysis. Solids were characterized by thermal analysis, X-ray diffraction, and infrared spectroscopy. Through batch experiments, the hydrotalcite capacity toward molybdate ions (1.12 × 10-3 M) was found to be 3.2 mequiv g-1. It was found that the high molybdate adsorbing capacity of calcined hydrotalcite could be utilized in designing a 99mTc generator made with low specific activity 99Mo-molybdate samples.

Combustion treatment of Co2+ and Cs+ exchanged zeolites

“…It was, then, washed several times with distilled water until the solution was free of chloride ions i.e. when AgCl did not precipitate when in contact with AgNO 3 solution [11]. Analytical reagents were used for both analyses and ion-exchange processes.…”

Synthesis and characterization of arsenate-intercalated layered double hydroxides (LDHs): Prospects for arsenic mineralization

“…Layered double hydroxides (LDHs) are widely used for catalysis and sorption and are sinks for the mineralization of insidious anions such as chromates [2,3], selenates [4], fluorides [5], radioactive anions [6], and various organic pollutants [7]. LDHs exhibit anion exchange properties, which make them candidate materials for the immobilization of arsenate in the interlayer region of the LDHs.…”

Sorption of99MoO42-ions on commercial hydrotalcites

“…This last description corresponds to well known devices called technetium generators [1][2][3] which are widely used in nuclear medicine as a diagnosis tool. Looking for other materials to bear the 99 Mo, Serrano et al [4] investigated the use of hydrotalcite (HT) as 99 Mo support to develop a new technetium generator. The most popular 99m Tc generator is the one in which alumina is the sorbent material.…”

“…The most popular 99m Tc generator is the one in which alumina is the sorbent material. However, since alumina's capacity to sorb molybdate is very low (37 mg/g), only high specific activity 99 Mo (as 99 MoO 4 2− ) obtained from fission products of 235 U can be utilized in this kind of 99m Tc generator. Besides, the fission 99 Mo production process involves the handling of fission products in a high radiation field.…”

“…The positive electrical charge is neutralized commonly by carbonate ions located in the interlayer space [5][6][7][8][9]. However, other compensating anions such as MoO 4 2− have also been used [4]. According to Cavani et al [7] pure hydrotalcite can be obtained only when 0.17 ≤ x ≤ 0.33, where x = Al 3+ /(Al 3+ + Mg 2+ ).…”