A Study Of Organic Sulfur Role On The Petroleum Hydrocarbon Generation

Due to the similarity between the hydrocarbon products from the hydrous pyrolysis of source rocks and the hydrocarbon in the crude oil, Hydrous pyrolysis (HyPy) is widely used in the assessment of petroleum hydrocarbon potential and petroleum resource of source rocks. Organic sulfur as an integrated part of organic matter in the source rocks, it certainly will experience the same maturation process as that of organic matter, although the mechanism(s) may be different. Therefore, it is possible to used hydrous pyrolysis approach to study the organic sulfur role on the petroleum hydrocarbon generation under a certain condition. This thesis has carried out a parall hydrous pyrolysis experiments with a sulfur depressor (Cadmium acetate, CdOAc) and without it on five careful chosen sample, i.e. Maoming brown coal, Maoming oil shale, Kunming Xianfeng brown coal, Taiyuan coal, and peat. By comparing the soluble organic matter and their hydrocarbon components produced from the parallel hydrous pyrolysis experiments, we aimed to asses the effect of organic sulfur on the generation of petroleum-like hydrocarbons. The following points could be concluded from this study:1. The sulfur depressor's effects on the different sediment samples is different and suggests that the organic sulfur role is somehow depended on the organic sulfur content and organic matter types. In general, sulfur depressor has no regular effect on the amount of hydrocarbon generation. However, as to the low organic sulfur sediments, when the sulfur depressor was added, the yield of petroleum hydrocarbon is somehow decreased while the distribution pattern of n-alkanes is unimodal or bimodal back-peak in the chromatograms of aliphatic hydrocarbons is also changed.2. In the most hydrous pyrolysates from the sediment samples when sulfur depressor were added, the soluble organic matter yields and their components show regular variation as the hydrous pyrolysis temperature change, compared to that of pyrolysates from the hydrous pyrolysis of their original samples without sulfur depressor;3. The addition of elemental sulfur into the hydrous pyrolysis of peat does not have clear effect on the yields of soluble pyrolysate, but it clearly imprint on the distribution of petroleum hydrocarbon such as shifts of dominant carbon number on the chromatograms of aliphatic hydrocarbons.