生物质锅炉氯腐蚀的密度泛函理论研究

doi:10.11949/0438-1157.20190487

摘要/Abstract

摘要：

氯气的活化氧化腐蚀是生物质锅炉过热器腐蚀的主要原因之一。为探究活化氧化腐蚀循环中FeCl₂与O₂的反应机理，本文利用Material Studio中的DMOl³模块，基于密度泛函和过渡态理论，优化了各反应物、产物、中间体和过渡态的几何构型。通过频率分析证实了中间体和过渡态的真实性。结果表明，FeCl₂与O₂反应生成Fe₃O₄的过程中逐次生成3个Cl₂分子，其中第三个Cl₂逸出生成Fe₃O₄需要吸收高达300.4 kJ/mol的能量，为反应路径的速率决定步骤。

关键词: 生物质燃料, 过热器, Cl₂, 活化氧化, 腐蚀, 分子模拟, 密度泛函理论

Abstract:

Activated oxidative corrosion of chlorine is one of the main causes of corrosion in biomass boiler superheaters. To investigate the reaction mechanism of FeCl₂ and O₂in the activated oxidation corrosion cycle, the DMOl³ module in Material Studio was used to optimize the geometry of each reactant, product, intermediate and transition state based on density functional theory and transition state theory. The authenticity of the intermediates and transition states was confirmed by frequency analysis. The results show that three Cl₂ molecules are successively formed during the reaction of FeCl₂ with O₂ to form Fe₃O₄. The third Cl₂ escaping to form Fe₃O₄needs to absorb up to 300.4 kJ/mol, which is the rate determining step of the reaction pathway.

Key words: biofuel, superheater, chlorine, activated oxidation, corrosion, molecular simulation, density functional theory

中图分类号:

TK 6

吕泽康, 龙慎伟, 李冠兵, 牛胜利, 路春美, 韩奎华, 王永征. 生物质锅炉氯腐蚀的密度泛函理论研究[J]. 化工学报, 2019, 70(11): 4370-4376.

Zekang LYU, Shenwei LONG, Guanbing LI, Shengli NIU, Chunmei LU, Kuihua HAN, Yongzheng WANG. Density functional theory study on chlorine corrosion of biomass furnace[J]. CIESC Journal, 2019, 70(11): 4370-4376.

图/表 8

表1 反应路径中各驻点的能量及过渡态的振动虚频

Table 1 Energies of various compounds and imaginary frequency of transition states

Species	E/Ha	Frequency/cm^-1	Species	E/Ha	Frequency/ cm^-1
O₂	-150.39	—	IM11	-1508.00	—
Cl₂	-920.42	—	IM12	-587.58	—
FeCl₂	-1063.80	—	IM13	-587.52	—
Fe₃O₄	-730.92	—	IM14	-1651.46	—
IM1	-1214.22	—	IM15	-1651.46	—
IM2	-1214.26	—	IM16	-1651.34	—
IM3	-2278.09	—	TS1	-1214.19	-869.50
IM4	-2278.16	—	TS2	-2278.08	-390.80
IM5	-2278.13	—	TS3	-2278.13	-119.00
IM6	-2278.03	—	TS4	-2278.03	-86.00
IM7	-1357.61	—	TS5	-1508.03	-817.10
IM8	-1508.06	—	TS6	-1508.02	-316.66
IM9	-1508.10	—	TS7	-1507.99	-22.66
IM10	-1508.04	—	TS8	-1651.43	-85.00

表2 反应物、生成物平均键长的计算值和文献值对比

Table 2 Average bond length of calculated values and literature values for reactant and product

Species	Bond type	Bond length/nm
Species	Bond type	Calculated	Literature
O₂	r(O—O)	0.1237	0.1220^[26]
Cl₂	r(Cl—Cl)	0.2076	0.2053^[27]
FeCl₂	r(Fe—Cl)	0.2156	0.2200^[28]
Fe₃O₄	r(Fe—O)	0.1843	0.1860^[29]

图1 中间体Cl2Fe2O2形成过程中各中间体和过渡态的几何构型（O:红色，Cl:绿色，Fe:蓝色；键长单位：nm)

Fig.1 Geometries of the intermediates and transition states involved in Cl2Fe2O2 formation(O: red, Cl: green, Fe: blue, bond length unit:nm)

图2 中间体Cl2Fe2O2形成过程的能量分布

Fig.2 Energy profiles of formation of Cl2Fe2O2

图3 Fe2O4形成过程中各中间体和过渡态的几何构型(键长单位：nm)

Fig.3 Geometries of the intermediates and transition states involved in Fe2O4 formation(bond length unit: nm)

图4 Fe2O4与Fe3O4形成过程中的能量分布

Fig.4 Energy profiles of formation of Fe2O4 and Fe3O4

图5 Fe3O4形成过程中各中间体和过渡态的几何构型(键长单位：nm)

Fig.5 Geometries of the intermediates and transition states involved in Fe3O4 formation(bond length unit: nm)

图6 FeCl2与O2反应机理示意图

Fig.6 Schematic illustration of reaction mechanism of FeCl2 and O2

参考文献 32

1	Khan A A , Jong W D , Jansens P J , et al . Biomass combustion in fluidized bed boilers: potential problems and remedies[J]. Fuel Processing Technology, 2009, 90(1): 21-50.
2	Tillman D A . Biomass cofiring: the technology, the experience, the combustion consequences[J]. Biomass & Bioenergy, 2000, 19(6): 365-384.
3	Dincer I . Renewable energy and sustainable development: a crucial review[J]. Renewable and Sustainable Energy Reviews, 2000, 4(2): 157-175.
4	Vassilev S V , Baxter D , Andersen L K , et al . An overview of the chemical composition of biomass[J]. Fuel, 2010, 89(5): 913-933.
5	Yu C , Qin J , Nie H , et al . Experimental research on agglomeration in straw-fired fluidized beds [J]. Applied Energy, 2011, 88(12): 4534-4543.
6	Nielsen H P , Frandsen F J , Dam-Johansen K , et al . The implications of chlorine-associated corrosion on the operation of biomass-fired boilers[J]. Progress in Energy and Combustion Science, 2000, 26(3): 283-298.
7	徐婧 . 生物质燃烧过程中碱金属析出的实验研究[D]. 杭州: 浙江大学, 2006.
	Xu J . Experimental study on alkali metal precipitation during biomass combustion [D]. Hangzhou: Zhejiang University, 2006.
8	Jensen P A , Frandsen F J , Dam-Johansen K , et al . Experimental investigation of the transformation and release to gas phase of potassium and chlorine during straw pyrolysis[J]. Energy&Fuel, 2000, 14(6): 1280-1285.
9	Nielsen H P . The implications of chlorine-associated corrosion on the operation of biomass-fired boilers[J]. Progress in Energy & Combustion Science, 2000, 26(3): 283-298.
10	岳茂振 . 秸秆类生物质与煤混燃过程中氯腐蚀规律研究[D]. 济南: 山东大学, 2011.
	Yue M Z . Study on the corrosion law of chlorine in the process of straw-based biomass and coal co-firing[D]. Jinan: Shandong University, 2011.
11	李至 . 生物质与煤混燃灰熔融特性及其影响研究[D]. 武汉: 华中科技大学, 2015.
	Li Z . Study on melting characteristics and effects of biomass and coal mixed combustion ash [D]. Wuhan: Huazhong University of Science and Technology, 2015.
12	Uusitalo M A , Vuoristo P M J , Mantyla T A . High temperature corrosion of coatings and boiler steels below chlorine-containing salt deposits[J]. Corrosion Science, 2004, 46(6): 1311–1331.
13	Grahke H J . Reese E, Spiegel M. The effect of chlorides, hydrogen chloride, and sulthr dioxide in the oxidation of steels below deposits[J]. Corrosion Science, 1995, 37(7): 1023-1043.
14	Berlanga C , Ruiz J A . Study of corrosion in a biomass boiler[J]. Journal of Chemistry, 2013, 2013(4): 1-8.
15	Zahs A , Spiegel M , Grabke H J . Chloridation and oxidation of iron, chromium, nickel and their alloys in chloridizing and oxidizing atmospheres at 400–700℃[J]. Corrosion Science, 2000, 42(6): 1093-1122.
16	邹潺, 王春波, 邢佳颖 . 煤燃烧过程中砷与氮氧化物的反应机理[J].燃料化学学报, 2019, 47(2): 138-143.
	Zou C , Wang C B , Xing J Y . Reaction mechanism of arsenic and nitrogen oxides in coal combustion process[J]. Journal of Fuel Chemistry and Technology, 2019, 47(2): 138-143.
17	贾建波, 曾凡桂, 李美芬, 等 . 用密度泛函理论研究煤中甲基苯生成甲烷的反应机理[J]. 化工学报, 2010, 61(12): 3235-3242.
	Jia J B , Zeng F G , Li M F , et al . Study on the reaction mechanism of methylbenzene to methane in coal by density functional theory[J]. CIESC Journal, 2010, 61(12): 3235-3242.
18	王荣杰, 沈本贤, 马健, 等 . 基于密度泛函的硫黄S8开环裂解机理[J]. 化工学报, 2015, 66(10): 3919-3924.
	Wang R J , Shen B X , Ma J , et al . Mechanism of open-loop cracking of sulfur S8 based on density functional theory[J]. CIESC Journal, 2015, 66(10): 3919-3924.
19	朱正和, 阎世英, 马美仲 . B₂H₆分子的几何构型[J]. 物理学报, 2005, 54(7): 3106-3110.
	Zhu Z H , Yan S Y , Ma M Z . Geometrical configuration of B₂H₆ molecule[J]. Acta Physica Sinica, 2005, 54(7): 3106-3110.
20	冯晓娜, 杨冬花, 武正簧, 等 . B、Al、La 同晶取代 EU-1 分子筛酸性的密度泛函理论计算[J]. 石油学报, 2013, 29(4): 647-654.
	Feng X N , Yang D H , Wu Z H , et al . Density functional theory calculation of the acidity of B, Al and La isomorphous substituted EU-1 molecular sieves[J]. Acta Petrolei Sinica, 2013, 29(4): 647-654.
21	田继权, 王伯初, 陈双扣, 等 . HClO对TYR氧化的理论研究[J]. 计算机与应用化学, 2011, 28(2): 217-221.
	Tian J Q , Wang B C , Chen S K , et al . Theoretical study on oxidation of TYR by HClO[J]. Computers and Applied Chemistry, 2011, 28(2): 217-221.
22	Zhang M , Wang W , Chen Y . Theoretical investigation of selective catalytic reduction of NO on MIL-100-Fe[J]. Physical Chemistry Chemical Physics, 2018, 20(4): 2211-2219.
23	黄金保, 刘朝, 魏顺安 . 纤维素热解形成左旋葡聚糖机理的理论研究[J]. 燃料化学学报, 2011, 39(8): 590-594.
	Huang J B , Liu C , Wei S A . Theoretical study on the mechanism of cellulose pyrolysis to form L-glucan[J]. Journal of Fuel Chemistry and Technology, 2011, 39(8): 590-594.
24	王小曼, 苏亚欣, 周皞, 等 . Fe₂与SO₂反应的密度泛函理论研究[J]. 原子与分子物理学报, 2017, 34(4): 625-629.
	Wang X M , Su Y X , Zhou H , et al . Density functional theory study on the reaction of Fe₂ with SO₂ [J]. Journal of Atomic and Molecular Physics, 2017, 34(4): 625-629.
25	侯封, 金晶, 王永贞, 等 . 污泥热解中 HCN 与 CaO 的反应机理: 密度泛函理论研究[J]. 燃料化学学报, 2017, 45(1): 123-128.
	Hou F , Jin J , Wang Y Z , et al . Reaction mechanism of HCN and CaO in sludge pyrolysis: density functional theory study[J]. Journal of Fuel Chemistry and Technology, 2017, 45(1): 123-128.
26	Reddy B V , Rasouli F , Hajaligol M R , et al . Novel pathway for CO oxidation on a Fe₂O₃ cluster[J]. Chemical Physics Letters, 2004, 384(4/5/6): 242-245.
27	迟绍明, 王宁, 马丽英, 等 . NO₃ ^-+Cl₂→ClONO₂+Cl^-反应势能面和势能阱[J]. 高等学校化学学报, 2008, 29(6): 1228-1233.
	Chi S M , Wang N , Ma L Y , et al . Potential energy surface and potential energy well of NO₃ ^-+Cl₂→ClONO₂+Cl^- [J]. Chemical Journal of Chinese Universities, 2008, 29(6): 1228-1233.
28	Bojana G P , Camaioni D M , Michel D . About the barriers to reaction of CCl₄ with HFeOH and FeCl₂ [J]. Journal of Physical Chemistry A, 2011, 115(31): 8713-8720.
29	Mejia-Olvera R , Reveles J U , Pacheco-Ortín S M , et al . Molecular dynamics and electronic structure study of neutral, cationic and anionic (Fe₃O₄) 1–5, clusters[J]. Chemical Physics Letters, 2018, 706(3): 494-500.
30	凌丽霞, 赵俐娟, 章日光, 等 . 苯甲酸和苯甲醛热解机理的量子化学研究[J]. 化工学报, 2009, 60(5): 1224-1230.
	Ling L X , Zhao L J , Zhang R G , et al . Quantum chemistry study on the pyrolysis mechanism of benzoic acid and benzaldehyde[J]. CIESC Journal, 2009, 60(5): 1224-1230.
31	徐建华, 胡常伟 . FeCH₂+H₂→Fe+CH₄反应机理的密度泛函理论研究[J]. 原子与分子物理学报, 2008, 25(2): 274-280.
	Xu J H , Hu C W . Density functional theory study on the reaction mechanism of FeCH₂+H₂→Fe+CH₄ [J]. Journal of Atomic and Molecular Physics, 2008, 25(2): 274-280.
32	Qin W , Chen Q L , Wang Y , et al . Theoretical study of oxidation-reduction reaction of Fe₂O₃ supported on MgO during chemical looping combustion[J]. Applied Surface Science, 2013, 266(2): 350-354.

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