𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Evaluation of the sealed-tube low-temperature combustion method for the 13C/12C and 2H/1H ratio determinations of cellulose nitrate

✍ Scribed by Fa-Xiang Tao; A.-M. Aucour; S. M. F. Sheppard; Cong-Qiang Liu; Xue-Tian Leng; Shi-Lu Wang; Guang-Shen Liu; Wen-Bir Xu


Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
571 KB
Volume
19
Category
Article
ISSN
0256-7660

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

Traditionally‐suggested combustion time of 1 h at 550°C) with the sealed‐tube combustion method for determining the ^13^C/ ^12^C ratio of cellulose nitrate or other nitrogen‐containing components could produce large negative deviation up to 1°. Three types of cellulose are used to ascertain possible causes. The presence of nitrous oxide (N~2~O) formed during combustion is most likely responsible for this deviation. Prolongation of the combustion time (at least 5 h at 550°C) and intimate contact between copper oxide and organic matter can greatly improve the analysis precision and effectively reduce this deviation to an acceptable level. Regardless of scattered carbon isotope data, hydrogen isotope data are all reproducible within 2° when this method is coupled with the high temperature uranium reduction method. Thus, care should be taken for determining carbon and nitrogen isotope compositions of nitrogen‐containing substances using the low temperature sealed‐tube combustion method.