Comparison of microscale sealed vessel pyrolysis (MSSVpy) and hydropyrolysis (Hypy) for the characterisation of extant and sedimentary organic matter
Comparison of microscale sealed vessel pyrolysis (MSSVpy) and hydropyrolysis (Hypy) for the characterisation of extant and sedimentary organic matter
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DOI：
10.1016/j.jaap.2009.10.009
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发表时间：
2010
影响因子：
6
通讯作者：
Lyndon Berwick;P. Greenwood;W. Meredith;C. Snape;H. Talbot
中科院分区：
文献类型：
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作者：
Lyndon Berwick;P. Greenwood;W. Meredith;C. Snape;H. Talbot
微型密闭容器裂解(MSSVpy)和催化加氢裂解(HHY)与气相色谱-质谱联用(HHY)是近年来出现的一种实用、通用的有机分析和表征方法。这两种热解方法现在都可以商业化，它们是对传统闪速热解分析的补充，传统的闪速热解分析可能会受到高结构极性热解产物过度降解或层析分辨率不足的限制。为了评估这两种热解方法的通用性和优点，将它们分别应用于几个反映不同热成熟度的有机样品。这一比较揭示了许多产品的相似之处，但也揭示了每个产品独有的几个重要特征。两者都是从细菌分离物和水过滤系统的膜生物絮凝剂中生产C27-C33Hopane产品。HHPY检测到的较高分子量和ββ立体异构体的浓度增加，反映了通过相应的LC-MS分析建立的主要C35(ββ-)细菌环多元醇前体的更多选择性键断裂，这归因于相对较短的停留时间和催化剂辅助的挥发温度的降低。当应用于生物降解原油的沥青质馏分时，两种热解方法都能够再生类似的液体正构烷烃分布，并通过生物降解从石油的游离相中去除诊断正构烷烃和甾烷生物标志物。只有MSSVpy程序的在线GC-MS分析才支持检测低分子量(<；C8)产品。这一优势在从富含S的克默里奇粘土中检测到低分子量烷基(<；C2)噻吩类化合物的MSSVpy中再次得到明显体现。用MSSVpy直接检测到高相对分子质量的烷基苯并噻吩类化合物和烷基二苯并噻吩类化合物的分布相似，并对海藻抽提物的极性组分进行了衍生化，这与先前用这两种方法对其他杂原子结合结构单元的灵敏检测一致。
Microscale sealed vessel pyrolysis (MSSVpy) and catalytic hydropyrolysis (Hypy) combined with gas chromatography–mass spectrometry have emerged in recent years as useful and versatile organic analytical and characterisation methods. Both now commercially available, these pyrolysis methods complement traditional flash pyrolysis analysis which can be limited by excessive degradation or inadequate chromatographic resolution of pyrolysates of high structural polarity. To assess the versatility and merits of these two pyrolysis methods they were separately applied to several organic samples reflecting different thermal maturities. This comparison revealed many product similarities, but also several important features unique to each. Both produced C27–C33hopane products from a bacterial isolate and a membrane biofoulant from a water filtration system. Increased concentrations of higher MW and ββ-stereoisomeric hopanes detected by Hypy reflect more selective bond cleavage, attributed to a relatively short residence time and catalyst assisted reduction of volatilisation temperatures, of the mostly C35(ββ-) bacteriohopanepolyol precursors established by corresponding LC–MS analysis. When applied to the asphaltene fraction of a biodegraded oil both pyrolysis methods were able to regenerate similar distributions of liquid n-alkanes and source diagnostic hopane and sterane biomarkers removed from the free phase of oil by the biodegradation. The detection of low MW (<C8) products was only supported with the online GC–MS analysis of the MSSVpy procedure. This advantage was again evident in the MSSVpy detection of low MW alkyl (<C2) thiophenes from the S-rich Kimmeridge clay. Similar distributions of higher MW alkyl benzothiophenes and alkyl dibenzothiophenes were detected directly by MSSVpy, and after derivatisation of the polar fraction of the Hypy extract, consistent with the sensitive detection of other heteroatom bound structural units previously demonstrated by both methods.