S. A. Kreek

Gas phase chromatography of halides of elements 104 and 105

On-line isothermal gas phase chromatography was used to study halides of261104 (T1/2=65 s) and262,263105 (T1/2=34 s and 27 s) produced an atom-at-a time via the reactions248Cm(18O, 5n) and249Bk(18O, 5n, 4n), respectively. Using HBr and HCl gas as halogenating agents, we were able to produce volatile bromides and chlorides of the above mentioned elements and study their behavior compared to their lighter homologs in Groups 4 or 5 of the periodic table. Element 104 formed more volatile bromide than its homolog Hf. In contrast, element 105 bromides were found to be less volatile than the bromides of the group 5 elements Nb and Ta. Both 104 and Hf chlorides were observed to be more volatile than their respective bromides.

Solution Chemistry of Element 104: Part I. Liquid-Liquid Extractions with Triisooctylamine

Liquid-liquid extractions of element 104 (Rf), Zr, Nb, Th, and Eu were conducted using triisooctylamine (ΠΟΑ), an organic soluble high molecular weight amine. Initial studies were conducted studying the extraction of Zr, Nb, Th and Eu from 12 M HCl in an organic phase of TIOA in benzene. Tracer loss due to thin sample formation was examined using Zr. Based on the tracer extraction results, Rf extractions were conducted with an aqueous phase of 12 M HCl and an organic phase of 1.0 M and 0.1 M TIOA in benzene. The Rf extraction results showed that 0.1 M TIOA in benzene extracts Rf to a greater extent than 1.0 M TIOA in benzene. This difference is attributed to Rf loss during thin sample formation. The extraction of Rf by ΤΊΟΑ is further evidence that Rf behaves similar to the group 4 elements.

Solution Chemistry of Element 104: Part II. Liquid-Liquid Extractions with Tributylphosphate

Liquid-liquid extractions of element 104 (Rf), Zr, Nb, Hf, Th, and Pu(IV) were conducted using tributylphosphate (TBP) in benzene. Initial studies were conducted using Zr and Nb. The effect of TBP, HCl, chloride, and hydrogen ion concentrations on Zr and Nb extraction was examined. Based on the results from these experiments, it was decided to examine Rf extraction into 0.25 M TBP in benzene as a function of HCl, chloride, and hydrogen ion concentrations between 8 and 12 M. Studies of these extraction conditions were carried out using Zr, Hf, Th, Pu, and Rf. The 65-second Rf was produced via the Cm(0,5n) reaction at the 88-Inch Cyclotron at Lawrence Berkeley Laboratory. The results show that extraction for these elements increases or remains high as a function of HCl concentration. However, in the experiments in which the chloride and hydrogen ion were varied, Rf extraction differed from that of the group 4 elements and behaved more like Pu(IV).

An automated, on-line rapid chemistry system

Abstract We have developed an automated chromatographic chemical element separation system (ACCESS) and an automated injection system (AIS) for rapid and reproducible ion-exchange separations of various chemical species. The system is modular to allow for many different separation configurations. Two high precision chromatography pumps, LDCs, provide constant solvent pressure throughout the system. An additional pump, and a six-way valve, permit the use of a total of up to eight different eluants in succession. The system is controlled by an IBM PC running a BASIC program. Chemical yield with the system has been determined to be 80±9%.