Quantitative Analysis Of Total Sulfur In CO₂ By Gas Chromatography With Flame Photometric

Beverage industry was a big market of our country's carbon dioxide, In China beverage consumption gradually increased with the increase of living standard. Domestic food preservation has been adopts mechanical refrigeration method, but in the process of storage for air drying, water shortage,etc,make food isn't fresh. Currently,international food storage widely using liquid carbon dioxide, dry ice freezing as a whole,it can prolong the shelf life. We use carbon dioxide to feed storehouse fumigation for 24 hours, and brake rate can reach 99%.Therefore, Food preservatives, carbonated drinks, food storehouse fumigation will be a huge potential market of carbon dioxide. So the control of food with carbon dioxide impurities will be more important.For food with total sulfur impurities in carbon dioxide detection. In the practical work found big drawbacks of the current detection method, in order to find a is more accurate and convenient detection method. In the original detection method based on improved screened agent suitable for removing sulfur dioxide and carbon dioxide in the total sulfur (except sulfur dioxide) impurities in the gas phase chromatography direct detection. The experiments of the paper are these conclusions.1. Adopt targeted SO2 removal column, in the effective removal of sulfur dioxide at the same time, has no sulphur damage except dioxide sulfur. Combined with the column without the separation of matrix determination of total sulfur FPD technology, can realize to the sulfur dioxide direct determination of total sulfur.2. In the range of the total sulfur control of food additives carbon dioxide and sulphur separation under tested without carbon matrix, a linear relationship between total sulfur content and the response values square roots, response regularity and GB/T28727-2012 [1] consistent standards; Under the given experimental condition, the total sulfur minimum values of 0.01×10-6 (V/V).3. Under the given experimental condition, with the same concentration (1.82 ×10-6 V/V) sulfide standard gas, adopting the method of this paper, the expanded uncertainty is 0.00566×10-6 (V/V). using the micro-coulomb method for testing, the expanded uncertainty is 0.072×10-6 (V/V), The uncertainty of measurement is much better than the micro-coulomb method.High chemical activity and physical adsorption of sulfur dioxide, which made the accurate determination of the low concentration range became an enduring problem. This research solved by two large value difference reduction to problem of big error of small quantity results, at the same time to avoid the loss in the process of sulfur dioxide in chromatographic separation affect the results. Accurate determination of the total sulfur execept sulfur dioxide, and it can quickly and accurately give the calculation results of sulfur dioxide.And through the comparison experiment and through testing the certified standard gas,it was concluded that this method was more accurate, reliable and convenient.