Effects of In-Process Hydrogenation on Mesophase Development

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Effects of in-process hydrogenation on mesophase development during the thermal condensation of petroleum aromatic-rich fraction Ming Li, Yadong Zhang, Shi-Tao Yu, Junwei Ding, Bing Bian, and Dong Liu Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/acs.energyfuels.7b03908 • Publication Date (Web): 13 Mar 2018 Downloaded from http://pubs.acs.org on March 14, 2018

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Energy & Fuels

1

Effects of in-process hydrogenation on mesophase

2

development during the thermal condensation of

3

petroleum aromatic-rich fraction

4

Ming Li a, Yadong Zhang a, b, Shitao Yu a, *, Junwei Ding a, Bing Bian a, c, Dong Liu b

5

a

6

Qingdao, China, 266042

7

b

8

Qingdao, China, 266580

9

c

10

College of Chemical Engineering, Qingdao University of Science and Technology,

State Key Laboratory of Heavy Oil Processing, China University of Petroleum,

College of Chemical and Environmental Engineering, Shandong University of

Science and Technology, Qingdao, China, 266590

11 12

Abstract: In this work, the mesophase pitch was generated from the thermal

13

condensation of petroleum aromatic-rich fraction. Tetrahydronaphthalene as hydrogen

14

donor was selected to treat the condensation intermediate using the in-process

15

hydrogenation method. The aim of this work was to investigate the effects of

16

in-process hydrogenation on the formation and development of mesophase structures.

17

Results showed that the intermediate after in-process hydrogenation possessed more

18

uniform molecular structure and narrower molecular-weight distribution compared to

19

the blank intermediate without in-process hydrogenation, which was attributed to the

20

increasing content of naphthenic structures in the intermediate. From the

21

characterization analysis of carbonized products, it can be found that the in-process

22

hydrogenation of condensation intermediate was conducive to the generation of

23

mesophase pitch with large domain structure, narrow molecular-weight distribution,

24

low softening point and carbon residue. 1

ACS Paragon Plus Environment

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1. Introduction

26

As the by-product of petroleum processing, the fluid catalytic cracking (FCC) slurry

27

oil is mainly used as fuel, asphalt modifier, rubber softener, or other low value-added

28

products, resulting in great waste and environmental pollution

29

FCC slurry oil with abundant polycyclic aromatic hydrocarbons is the ideal material

30

to prepared mesophase pitch which is widely recognized as excellent precursor of

31

high quality carbon materials

32

performance of petroleum-based mesophase pitch on the preparation of various

33

carbon materials

34

mesophase pitch is the hotspot and focus in the fields of carbon materials and

35

petroleum processing.

[4-7]

[1]

. Theoretically, the

[2, 3]

. Many researches have confirmed the outstanding

. Therefore, the study on preparation of petroleum-based

36

As previously reported, the influences of molecular structures of feedstock on

37

optical texture and rheological property of mesophase pitch have been studied widely

38

[8-10]

39

method to improve the properties of mesophase pitch

40

discussed the relationships between structure compositions of petroleum pitches and

41

optical textures of cokes. The structural composition of pitches is proved to be the

42

determining factor for the improvement of products’ optical textures. Miyake et al. [13]

43

have tried to monitor the effects of alkyl structures on the development of anisotropic

44

structures by introducing naphthenic groups via hydrogenation of mesophase pitch

45

precursor. They have found that the optical texture and anisotropic contents varied

46

depending on the number and steric size of alkyl groups in mesophase pitch

47

precursors. After studying the formation of mesophase pitch prepared by coal tar pitch

48

with tetrahydroquinoline as hydrogen donor, Yamada [14] and Oyabu [15] suggested that

. The hydrogenation of raw materials or mesophase precursors was quite effective [11-13]

2


. Menéndez et al.

[8]

have

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the softening point of carbonized product decreased, while the alkyl structures

50

increased after the hydrogenation of feedstock.

51

Additionally, a series of studies on pyrolysis of petroleum fraction with different

52

properties have shown that the molecular-weight distribution (MWD) of petroleum

53

fraction was mainly responsible for the changes in optical texture and microcrystal

54

structure of mesophase pitch [16-19]. Torregrosa-Rodrı́guez et al. [18] has investigated the

55

roles of petroleum pitches with different MWD played on the solubility and optical

56

textures of resultant cokes. They noted that the pitch with narrow MWD was easy to

57

generate a mesophase pitch with good rheological property and large domain structure.

58

Sparvoli et al.

59

petroleum pitch on the development of mesophase structure.

[19]

have also emphasized the significant influences of MWD of

60

These studies have reduced the chemical complexity of feedstock and confirmed

61

the importance influences of molecular structure and MWD of feedstock on the

62

properties of mesophase pitch. However, the regulation and control of structural

63

composition of intermediate products during the formative process of mesophase

64

structure has not been studied up to now. Given the above, the method of in-process

65

hydrogenation was used to regulate the molecular structure and MWD of intermediate

66

for obtaining high quality mesophase pitch in this work. The in-process hydrogenation

67

with hydrogen donor was generally used in the field of heavy oil visbreaking process.

68

However, there was no related research reporting that the hydrogen donor was

69

employed to treat the intermediate during the preparation of mesophase pitch. This

70

study focused on the influences of in-process hydrogenation on the optical textures

71

and physico-chemical property of mesophase pitches generated from petroleum

72

aromatic-rich fraction. Moreover, the effects of in-process hydrogenation on the

3


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regulation of molecular structure and MWD of hydrogenated intermediates were

74

investigated.

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2. Experimental section

76

2.1 Materials

77

The petroleum aromatic-rich fraction (named F), generated by the solvent

78

extraction of the vacuum distillate from the FCC slurry oil with furfural as solvent,

79

was provided by CNOOC Company. The average molecular weight (Mn), carbon

80

residue, elemental composition and SARA (including saturates, aromatics, resin and

81

asphaltene) of F are listed in Table 1. The feedstock F possessed high content of

82

carbon and low contents of sulphur and nitrogen. Additionally, the aromatics were

83

enriched in F, while no asphaltene was detected. It suggested that there was no

84

heptane-insoluble component (HI) in F.

85

Table 1 Elemental composition, average molecular weight and SARA of F. Elemental composition /wt. % Sample F

86 87 88

C

H

S

N

89.02

10.83

0.09

0.04

SARA /wt. % Mn 386.12

Saturates

Aromatics

Resin

Asphaltene

14.47

56.40

30.15

0

2.2 In-process hydrogenation and thermal treatment The preparation route of mesophase pitches by in-process hydrogenation method is shown in Figure 1. The detailed reaction conditions are as below.

89

(a) The thermal condensation of feedstock F was carried out in a batch-type

90

autoclave at 440 °C under 4 MPa of constant pressure. Before that, the system was

91

pressed with an initial N2 pressure. The intermediate obtained under the investigated

92

condition for 2.5 h was named FI.

4


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Energy & Fuels

(b) The intermediate FI was thermally treated at 400 °C under 6 MPa for 1.5 h,

93 94

and the resulting unhydrogenated intermediate was named M1. (c) The intermediate FI was thermally treated with 8

95

wt. % of

96

tetrahydronaphthalene (THN) as hydrogen donor at 400 °C under 6 MPa for 1.5 h,

97

and the resulting hydrogenated intermediate was named M2. (d) The mesophase pitch product of M1-MP was obtained by thermally treating

98 99

the unhydrogenated intermediate M1 at 440 °C under 4 MPa for 5 h. (e) The mesophase pitch product of M2-MP was obtained by thermally treating

100 101

the hydrogenated intermediate M2 at 440 °C under 4 MPa for 5 h.

102 103

Figure 1 Preparation route of mesophase pitches by in-process hydrogenation method.

104

2.3 Characterization

105

The elemental composition of feedstock was characterized by a PE-2400 Series

106

HCSN elemental analyzer. The SARA of feedstock was characterized according to the

107

SH/T 0509-98 standards. The carbon residues of feedstock, intermediates and

108

products were analyzed in accordance with ASTM D4530.The average molecular

109

weight of feedstock was analyzed by VPO method on a KNAUER K-7000 apparatus.

110

The solubility of intermediates and products were analyzed by dividing the samples

111

into four components via sequential extraction using heptane, toluene and quinolone

112

as

solvents.

Four

resultant

extracted

components:

5


heptane-soluble

(HS),

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(HI-TS),

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113

heptane-insoluble/toluene-soluble

toluene-insoluble/quinolone-soluble

114

(TI-QS) and quinolone-insoluble (QI) were obtained. The hydrogen distributions of

115

intermediates were determined by 1H NMR on a Bruker Avance DMX-500 NMR

116

spectrometer using deuterated chloroform as solvents. Penetrometer method

117

used to measure the softening point (SP) of mesophase pitch. The optical textures of

118

carbonized products were observed on a XPL-50 polarized microscope made by

119

Shanghai Milite Company.

120

3. Results and discussion

121

3.1 Characterization of intermediates

122

3.1.1 Solubility, carbon residue and elemental composition analyses

[21]

was

123

The contents of the extracted components, carbon residues and elemental

124

compositions of intermediates FI, M1 and M2 are listed in Table 2. The carbon residues

125

of the three intermediates increased as FI＜M2＜M1, while the variation tendency of

126

the H/C ratios of FI, M1 and M2 (1.067, 0.952 and 1.037, respectively) was consistent

127

with that of carbon residues. This indicated that the carbonization degree of M1 was

128

higher than those of FI and M2. In addition, the yield of M1 (79.5 wt. %) was higher

129

than that of M2 (87.2 wt. %). This could be explained by the hydrogen transfer

130

reaction which was caused by the hydrogen radicals provided by THN. The thermal

131

reaction was alleviated, and the viscosity of the reaction system was reduced by the

132

hydrogen transfer reaction. Then low systematic viscosity contributed to the

133

generation of polycyclic aromatic compounds with high molecular-weight by small

134

molecule compounds. This could reduce the spillage of the components with low

135

molecular weight from the system. As a result, the M2, produced by hydrogenation of

136

FI, possessed higher yield than M1.

6


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Energy & Fuels

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As shown in Table 1 and 2, there was no HI in F and no QI component in FI, while

138

5.78% of QI was found in M1. This meant that the MWD of the intermediates become

139

wider with reaction time

140

macromolecules in M1 could trigger the generation of mesophase spheres as initial

141

nucleus

142

mesophase. This resulted in the low H/C ratio and high carbon residue of M1. In

143

addition, M2 possessed more HI-TS and TI-QS components compared to M1, while no

144

QI can be found in M2. This demonstrated that the molecules of M2 were mainly

145

enriched in HI-TS and TI-QS, while the molecules of M1 were widely distributed in

146

the four extracted components. In other words, the molecules with similar structures

147

in M2 were concentrated in HI-TS and TI-QS according to similarity-intermiscibility

148

theory

149

those of M1. Furthermore, it was known that the average molecular weights of the

150

four extracted components in intermediate products increased as HS＜HI-TS＜TI-QS

151

＜QI during thermal condensation

152

distribution (MWD) of M2 was narrower than that of M1.

[8]

. The component QI with polycyclic aromatic

[8, 20]

[20]

, and thus the coke would appeared earlier during the preparation of

. It suggested that the molecular structures of M2 were more uniform than

[16, 22]

. This meant that that the molecular weight

153

During the hydrogenation process, the active α-hydrogen from THN could provide

154

hydrogen for alkane cracking, meanwhile, the existence of abundant α-hydrogen

155

could suppress the condensation reaction of polycyclic aromatic molecules with high

156

condensation degree

157

so there was no QI appeared in M2. But if there was no THN in the reaction system,

158

the hydrogen for alkane cracking were supplied by the naphthenic hydrocarbons and

159

polycyclic aromatic hydrocarbons in intermediate FI [13]. This resulted in the excessive

160

condensation of polycyclic aromatic molecules. Therefore, the heavy component QI

161

was generated in M1, and thus the MWD of M1 was wide. The above results suggested

[4, 15]

. This resulted in a long period before the generation of QI,

7


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that the molecular structures and MWD of intermediate could be regulated by the

163

contents of naphthenic structures in the intermediate during the in-process

164

hydrogenation.

165

Table 2 Extracted components, carbon residues and elemental compositions of FI, M1 and M2. Extracted component/wt. %

Carbon

Sample

166 167 168

Elemental composition/wt. %

HS

HI-TS

TI-QS

QI

residues/wt. %

C

H

S

N

FI

47.61

29.68

22.71

0

21.6

91.73

8.16

0.04

0.04

M1

32.53

32.26

29.43

5.78

29.5

92.56

7.34

0.04

0.03

M2

31.07

33.69

35.24

0

23.1

91.98

7.95

0.03

0.03

3.1.2 1H NMR analysis The 1H NMR spectra of M1 and M2 are shown in Figure 2, and the hydrogen distributions are summarized in Table 3.

169

8


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Energy & Fuels

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Figure 2 1H NMR spectra of intermediates: (a) M1 and (b) M2.

172

Table 3 Hydrogen distributions of F, FI, M1 and M2.

Sample

Hydrogen contents/% Har a

Hα b

Hβ c

Hγ d

Hn e

M1

49.97

29.48

9.94

8.47

2.14

M2

45.06

29.55

10.07

7.53

7.79

173

a

b

174

α-position to an aromatic ring (3.3-2.0 ppm); , aliphatic hydrogen in methyl or methylene group

175

in β-position to an aromatic ring (1.4-1.0 ppm); , aliphatic hydrogen in methyl or methylene

176

group in γ-position to an aromatic ring (1.0-0.5 ppm); , naphthenic hydrogen (2.0-1.4 ppm) [4].

, aromatic hydrogen (9.0-6.0 ppm); , aliphatic hydrogen in methyl or methylene group in c

d

e

177

As shown in Table 3, M1 contained higher content of Har hydrogens than M2, which

178

indicated that M2 possessed lower content of aromatic carbon, while higher content of

179

alkyl structures than M1 [4]. Compared with M1, the content of Hβ and Hγ hydrogens in

180

M2 changed little, while the content of Hn in M2 was higher obviously. This implied

181

that alkyl chains in M1 and M2 were similar, but M1 contained more naphthenic

182

structures than M2. To sum up, the condensation degree of the intermediate decreased, 9


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183

while the naphthenic structures increased after the in-process hydrogenation. Given

184

the solubility analyses of M1 and M2, the molecular structures and MWD of

185

intermediates were regulated by changing the content of naphthenic structures in the

186

reaction system. The increasing content of naphthenic structures in the reaction

187

system contributed to the generation of intermediate with uniform molecular structure

188

and narrow MWD.

189

3.2 Characterization of mesophase pitch

190

3.2.1 Optical texture analysis

191

Figure 3 presents the optical textures of mesophase pitches M1-MP and M2-MP.

192

The coarse mosaic structure [23] with a size in the range of 20µm~50µm was generated

193

in M1-MP, while the large domain structure with a size larger than 200µm was

194

appeared in M2-MP. This phenomenon could be explained by the differences of

195

molecular structures and MWD between M1 and M2. During the thermal condensation

196

of M1, the component QI with high condensation degree played a role as small

197

nucleus in accelerating the generation of mesophase spheres at the initial stage of

198

carbonization

199

aromatic molecular layers had no enough time to move and be rearranged orderly [4, 13].

200

So a coarse mosaic structure was generated in M1-MP. Moreover, the fast formation of

201

mesophase spheres resulted in the coking. On the other side, the large domain

202

structure in M2-MP was attributed to the abundant naphthenic structures in M2.

203

During the condensation of M2, hydrogen transfer reactions triggered by naphthenic

204

structures could moderate the violence of carbonization, improve the rheological

205

property and maintain low systematic viscosity of the reaction system for a long time

206

[10]

207

result, a mesophase pitch (M2-MP) with large domain structure was easily formed.

[20]

. This led to the increase of the system viscosity, and then the large

. This was conductive to the coalescence and growth of mesophase spheres. As a

10


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Energy & Fuels

208

The above suggested that the in-process hydrogenation improved the optical texture of

209

mesophase pitch by increasing the content of naphthenic structures in intermediate.

210 211 212

Figure 3 Optical textures of mesophase pitches: (a) M1-MP and (b) M2-MP.

3.2.2 Solubility, carbon residue and softening point analyses

213

The contents of the extracted components, carbon residues and softening points of

214

M1-MP and M2-MP are summarized in Table 4. Compared to M1-MP, the M2-MP

215

possessed higher contents of HI-TS and TI-QS, but lower content of HS and QI. This

216

implied that the molecules of M2-MP were mainly enriched in intermediate

217

components HI-TS and TI-QS. That is to say, the MWD of M2-MP was narrower than

218

that of M1-MP. Additionally, the carbon residue and softening point of M1-MP was

219

both higher than those of M2-MP.

220

The content of QI in M1-MP was higher obviously than that in M2-MP, which

221

resulted in a higher carbon residue of M1-MP. As mentioned above, the rheological

222

property of mesophase pitch was improved because many hydrogen transfer reactions

223

accrued during the carbonization reaction. The lower softening point of M2-MP was

224

attributed to the better rheological property of the reaction system. Then the time

225

when the petroleum coke appeared was prolonged. This resulted in a lower carbon

226

residue of M2-MP. Besides, the hydrogen transfer reactions avoided the overreaction

227

and prolonged the coking-induction period of coking

[20]

11


, so the MWD of products

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228

became narrow. To sum up, the in-process hydrogenation of intermediate was

229

conducive to the generation of mesophase pitch with large domain structure, narrow

230

MWD, low softening point and carbon residue. Table 4 Extracted components, carbon residues and softening points of M1-MP and M2-MP.

231

Sample

Extracted component/wt. %

residue/wt. %

HI-TS

M1-MP

10.06

13.17

21.45

55.32

85.07

294

M2-MP

8.41

14.88

33.46

43.25

81.56

231

f

233

4. Conclusion

QI

SP f/°C

HS

232

TI-QS

Carbon

, softening point.

234

The effects of in-process hydrogenation on the formation and development of

235

mesophase structures were investigated by analyzing the properties of intermediates

236

and mesophase pitches. Results showed that the intermediate after in-process

237

hydrogenation possessed more uniform molecular structure and narrower MWD

238

compared to the blank intermediate without in-process hydrogenation, which was

239

attributed to the increasing content of naphthenic structures in the intermediate. It was

240

also found that the in-process hydrogenation of intermediate was conducive to the

241

generation of mesophase pitch with large domain structure, narrow MWD, low

242

softening point and carbon residue. Moreover, the in-process hydrogenation regulated

243

the MWD of mesophase pitch by changing the content of napthenic structures in

244

intermediates.

245

Acknowledgment

246

This work has been supported by the Taishan Scholars Projects of Shandong

247

(ts201511033).

248

Notes 12


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Energy & Fuels

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The authors declare no competing financial interest.

250

References

251

[1] Li W, Chen Y, Zhang L, Xu Z, Sun X, Zhao S, Xu C. Supercritical fluid extraction

252

of FCC slurry oil: bulk property and molecular composition of narrow fraction.

253

Energy Fuel 2016, 30(12): 10064-10071.

254

[2] Kumar S, Srivastava M. Influence of presence/addition of asphaltenes on

255

semi-coke textures and mesophase development in petroleum feed stocks. Fuel 2016,

256

173(1): 69-78.

257

[3] Guo Y, Li Y, Ran N, Gao F. Co-carbonization effect of asphaltine and heavy oil in

258

mesophase development. J Mater Sci 2016, 51(5): 2558-2564.

259

[4] Liu D, Li M, Qu F, Yu R, Lou B, Wu C, et al. Investigation on preparation of

260

mesophase pitch by the co-carbonization of naphthenic pitch and polystyrene. Energy

261

Fuel 2016, 30(3): 2066-2075.

262

[5] Yue Z, Liu C, Vakili A. Solvated mesophase pitch-based carbon fibers:

263

thermal-oxidative stabilization of the spun fiber. J Mater Sci 2017; 52(13): 8176-8187.

264

[6] Liu Q, Qiao Y, Tian Y, Gu F, Zhong Z, Su F. Ordered mesoporous Ni-Fe-Al

265

catalysts for CO methanation with enhanced activity and resistance to deactivation.

266

Ind Eng Chem Res 2017, 56(35): 9809-9820.

267

[7] Liu Q, Wang S, Zhao G, Yang H, Yuan M, An X, Zhou H, Qiao Y, Tian Y. CO2

268

methanation over ordered mesoporous NiRu-doped Cao-Al2O3 nanocomposites with

269

enhanced catalytic performance. Int J Hydrogen Energ 2018, 43(1): 239-250.

270

[8] Menéndez R, Granda M, Bermejo J. Relationships between pitch composition and

271

optical texture of cokes. Carbon 1997, 35(4): 555-562.

13


Energy & Fuels 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

272

[9] Liu D, Lou B, Li M, Qu F, Yu R, Yang Y, et al. Study on the preparation of

273

mesophase pitch from modified naphthenic vacuum residue by direct thermal

274

treatment. Energy Fuel 2016, 30(6): 4609-4618.

275

[10] Lou B, Liu D, Li M, Hou X, Ma W, Lv R. Modified Effects of additives to

276

petroleum Pitch on the mesophase development of the carbonized solid products.

277

Energy Fuel 2016, 30(2): 796-804.

278

[11] Lin X, Ideta K, Miyawaki J, Takebe H, Yoon S H, Mochida I. Correlation

279

between fluidity properties and local structures of three typical Asian coal ashes.

280

Energy Fuel 2012, 26(4): 2136-2144.

281

[12] Mochida I, Korai Y, Ku C H, Watanabe F, Sakai Y. Chemistry of synthesis,

282

structure, preparation and application of aromatic-derived mesophase pitch. Carbon,

283

2000, 38(2): 305-328.

284

[13] Miyake M, Ida T, Yoshida H, Wakisaka S, Nomure M, Nishizawa T. Effects of

285

reductively introduced alkyl groups and hydrogen to mesophase pitch on

286

carbonization properties. Carbon 1993, 31(5): 705-714.

287

[14] Yamada Y, Matsumoto S, Fukuda K, Honda H. Optically anisotropic texture in

288

tetrahydroquinoline soluble matter of carbonaceous mesophase. Tanso, 1981, 107(1):

289

144-146.

290

[15] Oyabu M, Fukuda K, Hirata K. Process for producing carbon fibers. US, US

291

4320107 A. 1982.

292

[16] Fixari B, Perchec P L, Bigois M. Oxidative pyroanalysis: elemental analysis in

293

volatile and non-volatile fractions of coals and related materials. Fuel 1990, 69(7):

294

851-855.

14


Page 14 of 15

Page 15 of 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

295

[17] Chang Y C, Sohn H J, Ku C H, Wang Y G, Korai Y, Mochida I. Anodic

296

performances of mesocarbon microbeads (MCMB) prepared from synthetic

297

naphthalene isotropic pitch. Carbon 1999, 37(8):1285-1297.

298

[18] Torregrosa-Rodrı́guez P, Martı́nez-Escandell M, Rodrı́guez-Reinoso F, Marsh H,

299

Gómez de Salazar C, Romero Palazón E. Pyrolysis of petroleum residues: II.

300

Chemistry of pyrolysis. Carbon 2000, 38(4): 535-546.

301

[19] Sparvoli M, Mansano R D, Chubaci J F D. 04/00643 Mesophase development in

302

petroleum and coaltar pitches and their blends: Mora, E. et al. Journal of Analytical

303

and Applied Pyrolysis, 2003, 68–69, 409-424. Mol Cell Biol 1991, 11(4): 1854-1860.

304

[20] Liang W, Que G, Liu C, Yang Q. Petroleum chemisitry. Shandong, China

305

University of Petroleum Press. 2009: 58-78, 103-107.

306

[21] Cheng X. Modified characteristics of mesophase pitch by co-carbonization with

307

waste polystyrene. China University of Petroleum 2009.

308

[22] Li M, Liu D, Lv R, Ye J, Du H. Preparation of the mesophase pitch by

309

hydrocracking tail oil from a naphthenic vacuum residue. Energy Fuel 2015, 29(7):

310

4193-4200.

311

[23] Li M, Liu D, Lou B, Hou X, Chen P. Relationship between structural

312

modiﬁcation of aromatic-rich fraction from heavy oil and the development of

313

mesophase microstructure in thermal polymerization process. Energy Fuel 2016,

314

30(10): 8177-8184.

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