Zhang Zhiming, Yang Jiantao, Li Limei, Qian Jianqiang, Zhao Yong, Wang Tengfei
College of Forestry, Henan Agricultural University, Zhengzhou, China.
College of Forestry, Henan Agricultural University, Zhengzhou, China; Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China.
Bioresour Technol. 2021 Dec;342:125980. doi: 10.1016/j.biortech.2021.125980. Epub 2021 Sep 20.
In this study, persulfate was used during hydrothermal processing of spirulina (160℃-220℃) for enhancement of nitrogen conversion. The nitrogen distribution in aqueous phase, hydrochar and biocrude-oil was evaluated, and the elemental composition and chemical forms of hydrochar were investigated. Results suggested that the addition of persulfate during hydrothermal processing of spirulina increased the atomic N/O of hydrochar for 1.2%-2.4%, whereas the NH-N concentration in liquid phase increased by approximately 67-155 mg/L regardless of temperature, suggesting that the persulfate could facilitate the organic nitrogen degradation and protein deamination. The N1s XPS analysis indicated that the protein-N, pyrrole-N, and inorganic-N ratio in spirulina were decreased, while more pyridine-N in hydrochar was formed, suggesting that more stable N forms were generated. In addition, the elementary composition also showed that more N was formed on the surface of hydrochar instead of the core.
在本研究中，在螺旋藻水热加工过程（160℃ - 220℃）中使用过硫酸盐以提高氮转化率。评估了水相、水炭和生物原油中氮的分布，并研究了水炭的元素组成和化学形态。结果表明，在螺旋藻水热加工过程中添加过硫酸盐可使水炭的原子N/O增加1.2% - 2.4%，而液相中的NH-N浓度无论温度如何均增加约67 - 155 mg/L，这表明过硫酸盐可促进有机氮降解和蛋白质脱氨。N1s XPS分析表明，螺旋藻中的蛋白质-N、吡咯-N和无机-N比例降低，而水炭中形成了更多的吡啶-N，这表明生成了更稳定的氮形态。此外，元素组成还表明，水炭表面形成了更多的氮而非核心部位。
