A new detection system consisted of a flame ionization detector（FID） and a sulfur chemiluminescence detector（SCD） was developed for sensitive and interference free determination of total sulfur in natural gas by n...A new detection system consisted of a flame ionization detector（FID） and a sulfur chemiluminescence detector（SCD） was developed for sensitive and interference free determination of total sulfur in natural gas by non-separation gas chromatography. In this system, sulfur containing compounds and hydrocarbons were firstly burned in the FID using oxygen rich flame and converted to SO_2, CO_2 and H_2O, respectively. The products from FID were transported into the SCD with hydrogen rich atmosphere wherein only SO_2 could be reduced to SO and reacted with O_3 to produce characteristic chemiluminescence. Therefore, the chemiluminescence of CO found in conventional SCD were eliminated because CO_2 could not be reduced to CO under these conditions. The experimental parameters were systematically investigated. Limit of detection obtained by the proposed system is better than 0.5 mmol/mol for total sulfur and superior to those previously reported. The proposed method not only retains the advantages of the conventional SCD but also provides several unique advantages including no hydrocarbon interference, better stability, and easier calculation. The utility of this technique was demonstrated by the determination of total sulfur in real samples and two certified reference materials（GBW 06332 and GBW（E） 061320）.展开更多
Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative byproducts.However,sulfur compounds(SCs)ev...Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative byproducts.However,sulfur compounds(SCs)even at trace level(nmol/mol)are usually involved in cell construction and further H_(2)production,which would cause degradation of the catalysts and shorten the lifetime of the fuel cells.Moreover,the highly reactive SCs could cause varied species and concentrations of them in complex matrices,so online rather than offline analysis of SCs in H_(2)would be preferred.In this context,we developed a new system combining online cryogenic preconcentration of nine SCs and subsequent determination by GC-SCD(sulfur chemiluminescent detector),with the correlation coefficients of the calibration curves higher than 0.999,calculated limits of detection no higher than 0.050 nmol/mol,analytical time around 30 min per sample,and satisfactory precision and accuracy(RSD<5%and SD<15%).The analytical performance was much better than or at least comparable to the previously reported and the developed system was successfully applied for real sample analysis.展开更多
基金the National Science and Technology Supporting Plan(No.2013BAK12B04)for financial support
文摘A new detection system consisted of a flame ionization detector（FID） and a sulfur chemiluminescence detector（SCD） was developed for sensitive and interference free determination of total sulfur in natural gas by non-separation gas chromatography. In this system, sulfur containing compounds and hydrocarbons were firstly burned in the FID using oxygen rich flame and converted to SO_2, CO_2 and H_2O, respectively. The products from FID were transported into the SCD with hydrogen rich atmosphere wherein only SO_2 could be reduced to SO and reacted with O_3 to produce characteristic chemiluminescence. Therefore, the chemiluminescence of CO found in conventional SCD were eliminated because CO_2 could not be reduced to CO under these conditions. The experimental parameters were systematically investigated. Limit of detection obtained by the proposed system is better than 0.5 mmol/mol for total sulfur and superior to those previously reported. The proposed method not only retains the advantages of the conventional SCD but also provides several unique advantages including no hydrocarbon interference, better stability, and easier calculation. The utility of this technique was demonstrated by the determination of total sulfur in real samples and two certified reference materials（GBW 06332 and GBW（E） 061320）.
基金the financial support to this work by Sichuan Science and Technology,China(Nos.2019ZDZX0035&2018TZDZX0008)the Ministry of Education through the 111 Project(No.B17030).
文摘Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative byproducts.However,sulfur compounds(SCs)even at trace level(nmol/mol)are usually involved in cell construction and further H_(2)production,which would cause degradation of the catalysts and shorten the lifetime of the fuel cells.Moreover,the highly reactive SCs could cause varied species and concentrations of them in complex matrices,so online rather than offline analysis of SCs in H_(2)would be preferred.In this context,we developed a new system combining online cryogenic preconcentration of nine SCs and subsequent determination by GC-SCD(sulfur chemiluminescent detector),with the correlation coefficients of the calibration curves higher than 0.999,calculated limits of detection no higher than 0.050 nmol/mol,analytical time around 30 min per sample,and satisfactory precision and accuracy(RSD<5%and SD<15%).The analytical performance was much better than or at least comparable to the previously reported and the developed system was successfully applied for real sample analysis.
