为了明确海藻热解生物油的主要成分及热解工况对成分的影响，对海藻生物质（条浒苔、马尾藻）不同工况下热解制得的生物油进行气相色谱质谱联用分析。海藻类生物油成分除了含氮化合物外，主要是一些烃类、酮类、醛类、醇类和酚类化合物，以及较大分子量的羧酸及其衍生物，并包含了少量呋喃、吡喃、吡啶等衍生物的杂环化合物。条浒苔油中羧酸及其衍生物（37.85%）和烃类物质（16.61%）较多，而马尾藻生物油中甾族（30.16%）和醇类化合物（24.81%）较多，也检测出油酸、棕榈酸酯和花生酸。不同工况下产生的生物油在组成成分上非常相似，只是相对含量有所不同。热解温度对海藻油组分分布起了重要作用，而载气流量对热解海藻油组分分布的影响不明显。试验结果还表明海藻油中含氮化合物的形成主要与蛋白质的分解有关。海藻生物油相对于陆上植物热解生物油优点为高含烃量，低含氧量。海藻热解制油工艺中温度应控制在500～600℃之间，能达到较佳产油率和油品。%Though the work of pyrolysis of biomass for bio-oil has attained many achievements, the research on seaweed for bio-oil has been proceeding slowly. In this paper, fast pyrolysis experiments of algae biomass (Enteromorpha clathrata and Sargassum natans) were studied. Two kinds of algal bio-oil (Enteromorpha clathrata and Sargassum natans) obtained under different work conditions (400, 500, 600℃ and carried gas) were analyzed by using GC-MS analysis. Besides nitrogen-containing compounds, the major constituents of algal bio-oil were hydrocarbon, alcohols, ketones, aldehydes, and phenolic compounds, as well as large molecular weight carboxylic acids and their derivatives. The algal bio-oil also included a small amount of heterocyclic compounds (derivatives of furan, pyridine, pyran, etc.). It was seen from the comparison between two bio-oils that Enteromorpha clathrata bio-oil had lots of hydrocarbons, carboxylic acids and their derivatives, while Sargassum natans bio-oil contained many alcohols compounds and steroids. In addition, in Sargassum natans bio-oil, palmitate, oleic acid, and peanut acid were also detected. Furthermore, the pyrolysis mechanism of seaweed biomass was studied preliminarily. The GC-MS method was also applied to analyze the collected oil pyrolyzed from pure protein. It was shown that nitrogen-containing compounds occupied 50%in the product, and phenols and aldehydes accounted for a part of oil, while alcohols, ketones and ethers were not found. The results also indicated that aromatic hydrocarbons did not exist in oil of protein. Most nitrogen-containing compounds in algae pyrolytic bio-oil were in accordance with the decomposition of protein. It was found in the result that the nitrogen content in bio-oil of Enteromorpha clathrata was apparently higher than that of Sargassum natans, which was closely due to their protein content. In this paper, the effects of temperature and carrier gas on the behavior of seaweed fast pyolysis were analyzed. The oil, gas and coke production rates were obtained, respectively. The bio-oils pyrolyzed under different work conditions were very similar in composition, but the relative contents of the components were different. Significant difference analysis was used to analyze the results. Pyrolysis temperature played an important role on the distribution of algal bio-oil composition, while the influence of the carrier gas flow rate was not obvious. The carrier gas only had the effect on the contents of C11∼C15, nitrogen-containing compounds, and carboxylic acids and derivatives. The optimum temperature for algal pyrolytic bio-oil was determined to be from 500 to 600℃. Comparing bio-oil pyrolyzed from seaweed with that from terrestrial lignocelluloses biomass, it was obvious to find that the content of hydrocarbons in Enteromorpha clathrata and Sargassum natans bio-oil (obtained at the temperature of 500℃) was approximately 16.61% and 5.04%, respectively, while the content of hydrocarbons in lignocelluloses biomass was very low. Therefore, it can also be seen that the advantage of algal bio-oil is the high content of hydrocarbons. At the same time, the oxygen content of algal bio-oil is also lower than that of terrestrial biomass. However, seaweed also has disadvantages in that the content of nitrogen in algal bio-oil is higher than that in lignocelluloses biomass.
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