固体核磁碳结构参数的修正及其在煤结构分析中的应用

陈丽诗; 王岚岚; 潘铁英; 周扬; 张媛媛; 张德祥

固体核磁碳结构参数的修正及其在煤结构分析中的应用

1.
华东理工大学能源化工系煤气化及能源化工教育部重点实验室, 上海 200237
2.
华东理工大学分析测试中心, 上海 200237

基金项目:

国家重点研发计划项目 2016YFB0600303

详细信息

通讯作者:
张德祥, Tel:021-64252367, E-mail:zdx@ecust.edu.cn

本文的英文电子版由Elsevier出版社在ScienceDirect上出版(http://www.sciencedirect.com/science/journal/18725813).
中图分类号: TQ53
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- 被引次数: 0
出版历程
- 收稿日期: 2017-04-05
- 修回日期: 2017-06-20
- 网络出版日期: 2021-01-23
- 刊出日期: 2017-10-10

Calibration of solid state NMR carbon structural parameters and application in coal structure analysis

1.
Department of Chemical Engineering for Energy Resources, East China University of Science & Technology, Key Laboratory of Coal Gasification and Energy Chemical Engineering of Ministry of Education, Shanghai 200237, China
2.
Analysis and Research Center, East China University of Science and Technology, Shanghai 200237, China

Funds:

the National Key Research and Development Program of China 2016YFB0600303

摘要

摘要: 为消除¹³C CP/MAS/TOSS NMR测试中碳核NOE效应，获得相对准确的碳结构参数，考察了不同模型化合物的碳核NOE效应强度。结果表明，不同模型化合物碳谱分峰拟合的测试值与样品碳结构参数的理论值之间存在明显误差，其中，脂肪碳在25%-125%、芳香碳为4%-50%，NOE效应在固体核磁碳谱测试中影响显著。为此，将模型化合物脂肪碳和芳香碳的实测值和理论值进行回归分析，得到非线性回归方程。用该方程对9，10-二甲基蒽进行碳结构修正，发现修正后脂肪碳实测值与理论值之间误差由不修正时的119.60%减小至7.84%，芳香碳误差为由不修正时的-17.10%到1.11%，修正后误差均在10%以内；同时用该回归方程修正了不同煤的碳结构参数，发现不同煤未修正的H/C原子比与其元素分析H/C原子比误差在45%-53%，修正后误差只有4%-13%，与元素分析结果具有一致性，表明非线性回归方程能够方便、准确地消除固体核磁NOE效应，为煤中碳结构分析提供新的技术支撑。
- 煤结构 /
- 模型化合物 /
- NOE效应 /
- 固体核磁 /
- 碳结构参数
Abstract: Carbon structure parameters were obtained accurately, if the NOE effect of carbon nucleus has been eliminated in¹³C CP/MAS/TOSS NMR test. This study has investigated different model compounds NOE effect intensity. And the results show that there is an obvious carbon structure error between the fitting test value and theoretical value in the different model compounds. The aliphatic carbon error is 25%-125%, and the aromatic carbon is 4%-50%, the NOE effect has great influence in solid state NMR. Therefore, the nonlinear regression equation was obtained by regression analysis of the measured and theoretical values of the model compound aliphatic and aromatic carbon. And this equation was used to calibrate the carbon structure of 9, 10-dimethylanthracene. It is found that after calibration the error between the measured value and the theoretical value of the modified aliphatic is reduced from 119.60% to 7.84%. The error of the aromatic carbon is reduced from -17.10% to 1.11%. And the error is within 10%. Then, the carbon structural parameters of different coal are calibrated by the regression equation. It is found that the H/C error of different coal is 45%-53% compared with elements analysis, and the calibration error is only 4%-13%, which is consistent with the results of elemental analysis. It indicated that the nonlinear regression equation could easily and precisely correct the solid state NMR carbon nuclear NOE effects and also provides new technical support for analysis of carbon structure in coal.
- coal structure /
- model compounds /
- NOE /
- NMR /
- carbon structural parameters
注释:

1) 本文的英文电子版由Elsevier出版社在ScienceDirect上出版(http://www.sciencedirect.com/science/journal/18725813).

HTML全文

图 1 不同模型化合物¹³C CP/MAS/TOSS NMR以及分峰拟合图

Figure 1 Different model compounds¹³C CP/MAS/TOSS NMR and fitted spectra

(A): 3, 4-dimethyl benzoic acid; (B): sodium dodecyl benzene sulfonic acid; (C): 2-naphthalene acetic acid; (D): 2-methyl naphthalene; (E): 9-methyl anthracene

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图 2 理论脂肪碳与实测脂肪碳的关系

Figure 2 Correlation of theory and measured aliphatic carbon

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图 3 理论芳香碳与实测芳香碳的关系

Figure 3 Correlation of theory and measured aromatic carbon

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图 4 9, 10-dimethyl anthracene¹³C CP/MAS/TOSS NMR以及分峰拟合图

Figure 4 9, 10-dimethyl anthracene¹³C CP/MAS/TOSS NMR and fitted spectra

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图 5 小龙潭、内蒙胜利原煤、神木原煤¹³C CP/MAS/TOSS NMR谱图以及分峰拟合图

Figure 5 XLT, NMSL and SM¹³C CP/MAS/TOSS NMR spectra and fitted spectra

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表 1 不同煤种的工业分析与元素分析

Table 1 Proximate and ultimate analysis of different coals

Sample	Proximate analyses w/%				Ultimate analyses w_daf/%					H/C^e	O/C^f
Sample	M_ad^a	A_d^b	V_daf^c	FC_daf	C	H	N	S	O^d	H/C^e	O/C^f
XLT	16.68	10.21	55.62	44.38	68.94	4.72	1.86	1.21	23.26	0.822	0.253
NMSL	9.58	14.41	46.48	53.52	72.99	4.65	1.16	1.40	19.80	0.764	0.203
SM	3.78	8.63	37.97	62.03	84.24	4.99	1.08	0.32	9.37	0.711	0.083
^a: ad, air dry basis;^b: d, dry basis;^c: daf, dry ash-free basis;^d: by difference;^e: atomic ratio, H/C=(H%×12)/C%;^f: atomic ratio, O/C= (O%×12)/(C%×16)

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表 2 ¹³C NMR中不同类型碳对应的化学位移

Table 2 Main characters for different structural carbons in solid-state¹³C NMR spectra

Assignment	Location	Chemical shift δ	Characters
Aliphatic methyl	R-CH₃	14-22	f_al³
Aromatic methyl		22-26	f_al^a
Methylene	-CH₂,	26-37	f_al²
Quaternery sp³ C	-CH--C	37-50	f_al¹, f_al^*
Oxygen aliphatic carbon	R-O-R,	50-95	f_al^O
Protonated aromatic carbon		95-129	f_a^H
Aromatic bridgehead carbon		129-137	f_a^B
Aliphatic substituted aromatic carbon		137-149	f_a^S
Oxygen aromatic carbon		149-164	f_a^O
Carboxyl	RCOOH	164-190	f_a^CC¹
Quinone and carbonyl carbon	RCOR	190-220	f_a^CC2
abbreviations in table 2 are as follows: f_al³: fraction of aliphatic methyl carbon; f_al^a: fraction of aromatic methyl carbon; f_al²: fraction of methylene carbon; f_al¹: fraction of methine carbon; f_al^*: fraction of carbon that is aliphatic and either quaternary, methyl, or mobile methylene; f_al^O: fraction of total carbon associated with aliphatic ethers and alcohols; f_a^H: protonated aromatic carbon; f_a^B: bridgehead aromatic carbon; f_a^S: alkyl substituted aromatic carbon; f_a^O: oxygenated aromatic carbon; f_a^CC1: fraction of carboxyl, f_a^CC2: fraction of quinone and carbonyl carbons.

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表 3 不同模型化合物不同类型有机碳分布

Table 3 Carbon structure distributions of the different model compounds

Sample	Structure parameter distribution /%
Sample	f_al³	f_al^a	f_al²	f_al¹, f_al^*	f_al^O	f_al	f_a^H	f_a^B+ f_a^S+ f_a^O	f_a^CC1+ f_a^CC2	f_a
3, 4-dimethyl benzoic acid	0.00	40.42	0.00	0.00	0.00	40.42	33.42	15.27	0.00	59.58
sodium dodecyl benzene sulfonic acid	7.71	0.00	75.40	0.00	0.00	83.11	8.89	8.00	0.00	16.89
2-naphthalene acetic acid	0.00	0.00	11.92	0.00	0.00	11.92	64.80	11.24	12.04	88.08
2-methyl naphthalene	0.00	20.42	0.00	0.00	0.00	20.42	62.34	27.28	0.00	79.58
9-methyl anthracene	0.00	13.60	0.00	0.00	0.00	13.60	37.83	48.57	0.00	86.40

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表 4 不同模型化合物碳结构理论值与实测值比较

Table 4 Coal structure comparison of different models compound error theory and measured values

Sample	Aliphatic(f_al)			Aromatic(f_a)
Sample	measured value	theoretical value	relativeerror /%	measured value	theoretical value	relative error /%
3, 4-dimethyl benzoic acid	40.42	22.23	+81.80	59.58	77.77	-23.41
sodium dodecyl benzene sulfonic acid	83.11	66.67	+24.70	16.89	33.33	-49.30
2-naphthalene acetic acid	11.92	8.33	+43.10	88.08	91.67	-3.90
2-methyl naphthalene	20.42	9.09	+124.60	79.58	90.91	-12.50
9-methyl anthracene	13.60	6.67	+103.90	86.40	93.33	-7.40

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表 5 9, 10-二甲基蒽不同类型有机碳分布

Table 5 Carbon structure distributions of the 9, 10-dimethyl anthracene

Sample	Structure parameter distribution /%
Sample	f_al³	f_al^a	f_al²	f_al¹, f_al^*	f_al^O	f_al	f_a^H	f_a^B+ f_a^S+ f_a^O	f_a^CC1+ f_a^CC2	f_a
9, 10-methyl anthracene	0.00	27.45	0.00	0.00	0.00	27.45	35.85	36.70	0.00	72.55

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表 6 9, 10-二甲基蒽中碳结构实测值和理论值误差

Table 6 9, 10-dimethyl anthracene error theory and measured value

Sample	Aliphatic(f_al)			Aromatic(f_a)
Sample	measured value	theoretical value	relative error /%	measured value	theoretical value	relative error /%
9, 10-methyl anthracene	27.45	12.50	+119.60	72.55	87.50	-17.10

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表 7 9, 10-二甲基蒽修正后实测值和理论值误差

Table 7 9, 10-dimethyl anthracene error theory and calibrated values

Sample	Aliphatic(f_al)			Aromatic(f_a)
Sample	calibrated value	theoretical value	relative error /%	calibrated value	theoretical value	relative error /%
9, 10-methyl anthracene	13.48	12.50	7.84	86.53	87.50	-1.11

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表 8 修正后9, 10-二甲基蒽不同类型有机碳分布

Table 8 Carbon structure distributions of the 9, 10-dimethyl anthracene after calibration

Sample	Structure parameter distribution /%
Sample	f_al³	f_al^a	f_al²	f_al¹, f_al^*	f_al^O	f_al	f_a^H	f_a^B+ f_a^S+ f_a^O	f_a^CC1+ f_a^CC2	f_a
9, 10-methyl anthracene	0.00	13.48	0.00	0.00	0.00	13.48	42.76	43.77	0.00	86.53

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表 9 不同煤种不同类型有机碳分布

Table 9 Carbon structure distributions of the different coals

Sample	Structure parameter distribution /%
Sample	f_al³	f_al^a	f_al²	f_al¹, f_al^*	f_al^O	f_al	f_a^H	f_a^B	f_a^S	f_a^O	f_a^CC1	f_a^CC2	f_a
XLT	11.95	12.43	14.45	3.95	3.77	46.55	17.1	12.26	8.97	5.91	4.71	4.50	53.45
NMSL	4.93	15.61	11.53	2.78	6.58	41.43	23.80	10.48	7.57	8.24	5.76	2.72	58.57
SM	12.03	9.56	7.64	5.58	1.78	36.59	29.24	24.77	5.96	3.26	0.00	0.18	63.41

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表 10 修正后不同煤种不同类型有机碳分布

Table 10 Calibration of carbon structure distributions of the different coals

Sample	Structure parameter distribution /%
Sample	f_al³	f_al^a	f_al²	f_al¹, f_al^*	f_al^O	f_al	f_a^H	f_a^B	f_a^S	f_a^O	f_a^CC1	f_a^CC2	f_a
XLT	6.80	7.07	8.22	2.26	2.14	26.49	23.52	16.86	12.34	8.13	6.47	6.19	73.51
NMSL	2.70	8.53	6.29	1.57	3.37	22.46	31.51	13.87	10.02	10.91	7.62	3.61	77.54
SM	6.25	4.97	3.97	2.90	0.93	19.02	37.34	31.63	7.61	4.16	0.00	0.24	80.98

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表 11 不同煤种元素分析H/C原子比和NMR修正前后H/C原子比

Table 11 Different types of H/C before and after calibrated in ultimate analyses and NMR

Sample	Ultimate analyses H/C	NMR H/C	Error of ultimate analyses and NMR H/C /%	NMR calibrated H/C	Error of ultimate analyses and NMR calibrated H/C /%
XLT	0.822	1.196	45.46	0.856	4.15
NMSL	0.764	1.166	52.56	0.862	12.95
SM	0.711	1.061	49.19	0.772	8.69

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表 12 不同煤种修正前后的芳香度

Table 12 Different types of aromaticity before and after calibration

Sample	Tested aromaticity	Calibrated aromaticity
XLT	0.535	0.735
NMSL	0.586	0.775
SM	0.634	0.810

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