麦秸秆与黑龙江褐煤共热氧化法制备腐植酸及其结构分析

李艳玲; 陈曦; 张翠清; 李晓峰; 刘鹏; 陈文轩; 任素霞; 雷廷宙

doi:10.1016/S1872-5813(22)60033-1

麦秸秆与黑龙江褐煤共热氧化法制备腐植酸及其结构分析

doi: 10.1016/S1872-5813(22)60033-1

李艳玲^1,,
陈曦¹,
张翠清²,
李晓峰²,
刘鹏^1, ,,
陈文轩¹,
任素霞¹,
雷廷宙^1, ,

1.
常州大学城乡矿山研究院, 江苏常州 213164
2.
北京低碳清洁能源研究院, 北京 102211

基金项目: 国家重点研发计划（2021YFC2101604），常州市重点研发计划（农业科技支撑）（CE20212043) ，国家自然科学基金（51906021）和国家能源投资集团科技创新项目（GJNY-21-95）资助

详细信息

通讯作者:
E-mail: liupeng@cczu.edu.cn

china_newenergy@163.com

中图分类号: TQ536.1
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出版历程
- 收稿日期: 2022-03-20
- 修回日期: 2022-05-06
- 录用日期: 2022-05-09
- 网络出版日期: 2022-06-09
- 刊出日期: 2023-01-18

Preparation and structural analysis of humic acid by co-thermal oxidation of wheat straw and Heilongjiang lignite

1.
Institute of Urban and Rural Mines, Changzhou University, Changzhou 213164, China
2.
National Institute of Clean-and-low-carbon Energy, Beijing 102211, China

Funds: The project was supported by the National Key Research and Development Program of China (2021YFC2101604), Changzhou Key Research and Development Project (Agricultural Science and Technology support) (CE20212043), National Natural Science Foundation of China (51906021), and Technology Innovation Project of CHN ENERGY (GJNY-21-95).

摘要

摘要: 结合矿源腐植酸（HA）产率高及生化HA活性高的特点，本研究提出将低阶煤与生物质共热氧化制备复合型HA（MIXHA）的想法。将黑龙江褐煤（HL）及麦秸秆（WS）的混合物（MIX）在10%的HNO₃溶液中进行了共热氧化，制备了MIXHA。通过SEM、FT-IR、¹³C NMR等分析，重点从HA的宏观形貌及微观结构对比了MIXHA与HL、WS分别单独制备的矿源HA、生化HA，分析HL与WS在共热氧化过程的协同作用。结果表明，MIXHA含量高于理论值， HNO₃分子的分解产生的活性氧原子、氮氧化物进攻HL与WS的分子结构，由于氢键重排、糖苷键断裂、交联等作用，WS纤维素与半纤维素产生的大量烷基自由基结合在HL缩合芳环上被氧化产生的醌基、羧基的邻对位，从而将芳香环上的质子碳转化为脂肪取代碳。得到的MIXHA含氧官能团丰富、活性高，FT-IR谱图具有明显的特征峰。本研究为低阶煤与农林废弃物的分级、资源化利用提供了一种新思路。
- 腐植酸 /
- 生物质 /
- 褐煤 /
- 共热氧化 /
- 固体碳核磁
Abstract: Combining with the characteristics of high yield of mineral humic acid (HA) and high activity of biochemical HA, co-thermal oxidation of low rank coal and biomass to produce complex HA (MIXHA) was newly proposed. The mixture (MIX) of Heilongjiang lignite (HL) and wheat straw (WS) was co-thermally oxidized in 10% HNO₃ solution to prepare MIXHA. This work focused on comparison of the macro morphology and microstructure of MIXHA between HLHA and WSHA by SEM, FT-IR and ¹³C NMR analyses, and explored the synergistic effect between HL and WS during the co-thermal oxidation process. The results show that MIXHA content is higher than the theoretical value. Decomposition of HNO₃ molecular produces active oxygen atoms and nitrogen oxides to attack the molecular structure of WS and HL. Due to hydrogen bond rearrangement, glycosidic bond rupture, and crosslinking, plenty of alkyl radicals generated in WS are combined with the condensation aromatic ring in HL. Thus, the protonated aromatic carbon is changed into aliphatic substituted aromatic carbon. The obtained MIXHA is rich in oxygen-containing functional groups, and has high activity. Obvious characteristic peaks are observed in FTIR spectra of MIXHA. This work would provide a new idea for classification and resource utilization of low-rank coal and agricultural and forestry wastes.
- humic acid /
- biomass /
- lignite /
- co-thermal oxidation /
- ¹³C NMR

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FIG. 2090. FIG. 2090.

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图 1 原料、OR、ER的SEM照片

Figure 1 SEM images of raw materials, OR, and ER

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图 2 HA产品示意图

Figure 2 HA product image

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图 3 不同HA的M值

Figure 3 M values of different HAs

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图 4 不同HA的FT-IR光谱谱图

Figure 4 FT-IR spectra of different HAs

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图 5 不同HA的 FT-IR光谱的拟合曲线

Figure 5 Fitting curves of FT-IR spectra of different HAs

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图 6 不同HA的 ¹³C NMR分峰拟合模拟

Figure 6 Peak fitting simulation of ¹³C NMR spectra of different HA

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表 1 原料的工业分析及元素分析

Table 1 Proximate and ultimate analyses of raw materials

Sample	Proximate analysis w/%				Ultimate analysis w_daf/%
Sample	M_ad	A_d	V_daf	FC_daf	C	H	N	S	O^a
HL	24.82	21.10	49.75	50.25	72.39	5.50	0.70	0.62	26.29
WS	10.55	10.43	79.63	20.37	50.05	7.30	0.57	0.02	42.06

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表 2 OR中${\varphi}_{{\rm{HA}}}$及工业分析、元素分析

Table 2 Proximate and ultimate analyses of OR

Sample	${\varphi}_{{\rm{HA}}}$	Proximate analysis w/%				Ultimate analysis w_daf/%
Sample	${\varphi}_{{\rm{HA}}}$	M_ad	A_d	V_daf	FC_daf	C	H	N	S	O^a
HLOR	51.65	4.89	49.57	72.79	27.21	71.58	6.53	5.16	0.31	16.41
WSOR	13.84	7.62	0.87	83.81	16.19	42.88	5.40	0.97	0.00	50.75
MIXOR	37.46	6.44	24.89	75.62	24.38	49.22	5.38	2.06	0.00	43.35

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表 3 三种HA的工业分析、元素分析与含氧官能团含量

Table 3 Proximate and ultimate analyses, and contents of O-containing functional groups in HA

Sample	Proximate analysis w/%				Ultimate analysis w_daf/%					O-containing functional groups w_daf/(mmol·g⁻¹)
Sample	M_ad	A_d	V_daf	FC_daf	C	H	N	S	O^a	−COOH	−ph−OH	total acidic groups
HLHA	4.78	13.63	61.23	38.77	60.40	5.90	3.54	0.18	29.98	2.50	2.91	5.41
WSHA	4.32	7.01	62.51	37.49	50.04	5.68	3.82	0.08	40.38	2.22	3.57	5.79
MIXHA	3.59	14.46	62.82	37.18	59.30	5.71	3.75	0.22	31.03	5.74	6.98	12.72

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表 4 不同HA中各含氧官能团面积百分比

Table 4 Area percentage of oxygen-containing functional groups in FT-IR spectra

Wavenumber /cm⁻¹	Assignment	Area percentage/%
Wavenumber /cm⁻¹	Assignment	HLHA	WSHA	MIXHA
1690−1720	C−O，ketone，aldehyde and −COOH	16.40	12.73	15.04
1600−1660	conjugated C=O	6.45	15.46	21.87
1450−1600	aromatic C=C	14.56	13.24	3.23
1375−1450	CH₃−Ar，CH₃ and CH₂	11.29	14.97	10.39
1300−1375	CH₂−C=O	9.95	6.28	5.83
1100−1300	C−O phenol	21.25	23.12	20.46
1000−1110	ash，alkyl ethers，Si−O and aryl ethers	20.10	14.18	23.18

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表 5 HA中不同结构的碳在¹³C NMR谱中对应的化学位移及相对含量

Table 5 Chemical shift and relative content of different types of carbons in HA

Chemical shift δ	Assignment	Area percentage/%
Chemical shift δ	Assignment	HLHA	WSHA	MIXHA
15	fat-methyl carbon	9.62	3.66	1.38
20	aromatic-methyl carbon	12.73	4.34	5.31
25	methylene carbon	9.26	6.31	7.17
31	methylene carbon	8.96	20.90	21.44
42	quaternary carbon, methine carbon	−	3.66	2.00
49	quaternary carbon, methine carbon	−	−	0.83
56	methoxy carbon	1.17	3.64	4.56
75	oxygen to methine carbon	8.59	10.36	5.57
84	oxygen to methine carbon	3.87	3.44	5.76
89	oxygen to methine carbon	−	−	2.76
107	acetal ketal carbon	3.81	6.59	1.83
111	aromatic proton carbon	2.27	−	−
116	aromatic proton carbon	4.18	6.27	4.48
122	aromatic bridgehead carbon	−	3.63	−
126	aromatic bridgehead carbon	4.90	−	4.27
132	alkyl aromatic carbon	8.68	3.88	5.93
135	alkyl aromatic carbon	−	1.77	−
139	alkyl aromatic carbon	−	−	2.23
142	alkyl aromatic carbon	−	−	1.26
151	aryl-O carbon	7.22	11.25	1.96
155	aryl-O carbon	−	−	4.34
160	carboxyl and amide carbons	−	−	1.06
167	carboxyl and amide carbons	4.45	−	0.30
176	carboxyl and amide carbons	6.36	9.61	9.19
185	aldehyde and ketone carbons	1.86	−	6.37
202	aldehyde and ketone carbons	2.05	0.69	−

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表 6 不同HA的不同类型碳的分布

Table 6 Distribution of different types of carbon in HA

Chemical shift δ	Assignment		Area percentage/%
Chemical shift δ	Assignment		HLHA	WSHA	MIXHA_E	MIXHA_T
15	f_al³	aliphatic methyl carbon	9.62	3.66	1.38	6.64
20	f_al^3a	aromatic methyl carbon	12.73	4.34	5.31	8.54
25−31	f_al²	methylene carbon	18.22	27.21	28.61	22.72
35−50	f_al¹ f_al^*	quaternary carbon, tertiary carbon	0	3.66	2.83	1.83
50−95	f_al^O	aliphatic carbon attached to O	13.64	17.44	18.65	15.54
95−110	f_al^OO	acetal ketal carbon	3.81	6.59	1.83	5.20
110−120	f_a^H	aromatic proton carbon	6.45	6.27	4.48	6.36
120−130	f_a^B	aromatic bridgehead carbon	4.90	3.63	4.27	4.27
130−150	f_a^S	alkyl aromatic carbon	8.68	5.65	9.42	7.17
150−160	f_a^O	aromatic carbon attached to O	7.22	11.25	6.30	9.24
160−180	f ^COO	carboxyl and amide carbons	10.81	9.61	10.55	10.21
180−220	f ^CO	aldehyde and ketone carbons	3.91	0.69	6.37	2.30
	f ^O	carbon in oxygen-containing functional groups	35.59	38.99	41.87	37.29

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