Mutual Influences between Organic Matter and Minerals during Oil

Subscriber access provided by UNIV OF TEXAS DALLAS

Fossil Fuels

Mutual influences between organic matter and minerals during oil shale pyrolysis Zhenghua Lu, Xiaosheng Zhao, Zhenyu Liu, and Qingya Liu Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/acs.energyfuels.8b03703 • Publication Date (Web): 04 Feb 2019 Downloaded from http://pubs.acs.org on February 7, 2019

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 35 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

1

Mutual influences between organic matter and minerals during oil

2

shale pyrolysis

3

Zhenghua Lu, Xiaosheng Zhao, Zhenyu Liu and Qingya Liu

4

State Key Laboratory of Chemical Resource Engineering, Beijing University of

5

Chemical Technology, Beijing 100029

6

Abstract: To better understand the mutual influence between organic matter and

7

minerals during oil shale pyrolysis, Huadian oil shale was treated by HCl-HF acids

8

and 8 dominant minerals were added separately into the resulting oil shale for

9

pyrolysis. The pyrolysis experiment was performed on a thermogravimetric analyzer

10

coupled with a mass spectroscopy (TG-MS) and the influence was discussed from the

11

viewpoints of mass loss of organic matter and release of light volatile products (CH4,

12

C2H6, C3H8, C4H10, C6H6, C7H8, C6H6O, H2, H2O, CO and CO2). Results indicate that

13

the organic matter or pyrolysis products delay(s) the release of water in clays. All the

14

minerals have little effect on the decomposition of organic matter and CaCO3,

15

kaolinite and TiO2 also have little effect on the volatiles reaction; while K2CO3,

16

Na2CO3, MnCO3, montmorillonite and Fe2O3 influence the volatiles reaction in

17

different ways which were discussed in detail in this work.

18

Key words: Oil shale; minerals; organic matter; mutual influence; TG-MS

19

1. Introduction

20

Oil shale is an important unconventional hydrocarbon resource with composition of

21

approximately 15–50 wt % organic matter and 50–85 wt % inorganic mineral.1 The



Corresponding author. E-mail: [email protected] 1

ACS Paragon Plus Environment

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

22

mineral consists mainly of carbonates, clays, metal oxides, quartz and pyrite.2

23

Pyrolysis or retorting is a major technology to convert oil shale’s organic matter to

24

shale oil and fuel gas. In this process, minerals were reported to have significant

25

influences on the pyrolysis of organic matter.3-11

26

The influences were studied mostly by demineralization and then evaluating the

27

changes in mass loss, products yield or kinetics during pyrolysis. Espitalie et al.3

28

found that the kerogen of Cameroon oil shale yielded more liquid hydrocarbons than

29

the raw oil shale during pyrolysis in a fixed bed reactor, suggesting inhibiting effect

30

of minerals. Yan et al.4 studied the overall effect of inherent minerals on Huadian oil

31

shale pyrolysis using TG-FTIR and reported that the mass loss and the amount of gas

32

product were reduced by demineralization. Aboulkas et al.5 found that the temperature

33

of maximum devolatilization rate of kerogen was 10 °C lower than that of the raw oil

34

shale (Morocca), concluding that the inherent minerals inhibited the decomposition of

35

kerogen. The effects of different minerals were investigated mainly by stepwise

36

demineralization. Karabakan et al.6 reported that alkali and alkaline earth carbonates

37

promoted the pyrolysis of organic matters from Göynük and Green River oil shale by

38

analyzing the change in pyrolysis activation energy before and after HCl treatment.

39

Ballice et al.7 drawn the same conclusion as that of Karabakan et al. based on the

40

phenomenon that the yield of volatile hydrocarbons was decreased by HCl treatment.

41

However, Al-Harahsheh et al.8 found that the total oil and gas yield increased when

42

Jordan oil shale was subjected to HCl treatment, which is clearly different from the

43

observations of Ballice and Karabakan. Ballice et al.7 also reported that inherent 2


Page 2 of 35

Page 3 of 35 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

44

silicates (clay minerals) had inhibiting effect on the pyrolysis of organic matter from

45

Turkey oil shale at 450-650 °C based on an increased yield of volatile hydrocarbons

46

after HF treatment. Chang et al.9 found that inherent clay minerals of Huadian oil

47

shale inhibited the formation of shale oil but promoted the formation of gas and water

48

by demineralization. We recently studied the influence of inherent minerals on

49

pyrolysis of Yilan oil shale using a TG-MS and deduced that calcite and iron oxide

50

promoted the decomposition of organic matter to form volatile and montmorillonite

51

promoted the reaction of volatiles to form coke and gas.10

52

In fact, treatment of oil shale with one acid usually removes a variety of minerals.

53

For example, HCl treatment could remove carbonates as well as some metal oxides.

54

Therefore, the results obtained by demineralization are generally the comprehensive

55

effects of several minerals and it is difficult to distinguish the influence of each

56

mineral. Although some conclusions have been drawn by demineralization method,

57

they are more or less deductive. Since the organic matter is physically surrounded by

58

minerals,1,12 addition of mineral to the organic matter were taken by some researchers

59

to investigate the influence of individual mineral. Lai et al.13 introduced metal oxides

60

into the organic matter of Yilan oil shale to study the effect of shale ash on pyrolysis.

61

They reported that CaO and Na2O inhibited coke formation while Fe2O3 promoted the

62

cracking of shale oil to form coke and gas. Hu et al.11 introduced calcite,

63

montmorillonite, gypsum and kaolinite into kerogen at a mineral to kerogen ratio of 9

64

in mass and studied their effects using an aluminum retort. They found that calcite

65

decreased the oil yield by 9.3 wt % and increased the gas yield by 4.2 wt%, 3


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

66

montmorillonite and gypsum increased the oil and gas yields, and kaolinite had little

67

effect.

68

Moreover, it was reported that coal char may promote decomposition of some

69

carbonates14,15 and the initial decomposition temperature of Na2CO3 reduced from

70

855 °C for pure Na2CO3 to 602 °C in the presence of char.15 If this observation

71

applies to the oil shale pyrolysis, the decomposition of carbonates will contribute to

72

the mass loss, which may be mistaken as the promoting effect of carbonates on

73

organic matter pyrolysis. To our knowledge, the mutual influence between organic

74

matter and minerals is rarely investigated during oil shale pyrolysis.

75

Based on the above analysis, eight minerals were mixed individually with HCl-HF

76

-treated Huadian oil shale and the mixtures were subjected to pyrolysis on a

77

thermogravimetric analyzer coupled with a mass spectrometer (TG-MS) to understand

78

mutual influence between organic matter and each mineral. The minerals and organic

79

matter were also pyrolyzed separately and the results were taken as backgrounds to

80

deduct interference of mineral decomposition on evaluation of the influence.

81

2. Experimental section

82

2.1. Materials

83

The oil shale used in this work was from Dachengzi Mine located in Huadian of

84

Jilin province in China and termed as HDOS. They were ground and sieved to 60-100

85

mesh, and then demineralized by acid treatments. The acids used include HCl (18.5

86

wt %) and a mixture of HCl (18.5 wt %) and HF (40 wt %). The oil shale and HCl

87

solution were mixed at a ratio of 10 g to 100 mL in a flask, stirred for 5 h at 65 °C 4


Page 4 of 35

Page 5 of 35 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

88

under a nitrogen atmosphere. The solid was then separated and rinsed with deionized

89

water at 50-60 °C until the filtrate was neutral. The HCl-treated oil shale was termed

90

as HDOS-C. HDOS-C was treated by a mixture of 50 ml HF and 50 ml HCl and the

91

resulting sample was termed as HDOS-CF. The HNO3 treatment which is widely used

92

to remove pyrite was not performed because this treatment may cause oxidation of

93

organic matter.16

94

Eight compounds with purities of higher than 98%: CaCO3, K2CO3, Na2CO3,

95

MnCO3, kaolinite, montmorillonite, Fe2O3 and TiO2 were selected based on the

96

analysis results of minerals in Huadian oil shale. They were ground and screened

97

through a 100 mesh sieve and mixed with HDOS-CF at the ratio of 1:1 in mass to

98

study their mutual influence during pyrolysis.

99

2.2 Pyrolysis experiment

100

Pyrolysis experiment was performed on a TG (Setsys Evolution 24, Setaram)

101

coupled with a MS (Omnistar 200, Balzers). The mixture of HDOS-CF and mineral

102

with total mass around 15 mg was loaded into the quartz crucible in TG, heated to

103

110 °C in an Ar flow with a rate of 100 mL/min and maintained for 20 min to remove

104

moisture. The mixture was then heated to 600 °C at a rate of 20 °C /min and

105

maintained for 20 min. Each experiment was repeated at least twice to ensure

106

repeatability and accuracy of the experimental data. Results indicate that the relative

107

standard deviation of mass loss is less than 0.5%.

108

The outlet of TG was connected with the MS through a hot stainless steel capillary

109

at about 180 °C to monitor the gaseous products on-line. To eliminate the effect of 5


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

110

baseline change in MS signal, the ion intensity of each product was divided by that of

111

Ar (m/z = 40) at the same time-on-stream and the corrected intensity was normalized

112

based on the total mass.

113

2.3 Characterization

114

Ultimate analysis was performed on an Elemental Analyzer (Vario EL, Germany).

115

Proximate analysis was performed on the TG and the detailed procedure can be found

116

in our previous work.10

117

X-ray diffraction (XRD) was carried out on a D8FOCUS X-ray diffractometer

118

(Brook) equipped with Cu Kα1 (λ = 0.15406 nm) radiation operated at 40 kV and 200

119

mA. The samples were scanned over a 2θ range of 5-80° at a frequency of 2° min-1.

120

X-ray fluorescence (XRF) was carried out on a S4-Explorer X-ray fluorescence

121

spectrometer (Bruker) under the sequential scanning mode. The maximum voltage is

122

60 KV and the maximum current is 170 mA.

123

The filtrate obtained during the acid treatment of oil shale was characterized by

124

inductively coupled plasma optical emission spectroscopy (ICP-OES, Perkin-Elmer

125

Optima) to identify the main metal elements.

126

3. Results and discussion

127

3.1 Characterization of minerals

128

Results of proximate and ultimate analyses of HDOS and HDOS-CF are

129

summarized in Table 1. The ash content is as high as 70.27% for HDOS and reduced

130

to 15.65% after demineralization process. Figure 1 shows the XRD spectra of HDOS

131

and the acid treated samples. It can be seen that the minerals in HDOS include quartz 6


Page 6 of 35

Page 7 of 35 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

132

(SiO2), montmorillonite {(Na,Ca)0.33(Al,Mg)2[Si4O10](OH)2·nH2O}, calcite (CaCO3),

133

kaolinite [Al2Si2O5(OH)4], hematite (Fe2O3) and pyrite (FeS2). The HCl treatment

134

removed calcite and hematite and had little influence on other minerals (see

135

HDOS-C). The subsequent HCl+HF treatment eliminated quartz, montmorillonite and

136

kaolinite as reported in literatures9,10 while the diffraction peaks of pyrite become

137

sharper. Meanwhile, a broad peak appears between 15-25o which is assigned to

138

amorphous carbon in organic matters, and several small peaks appear at 15o, 39o, 44o

139

and 51o which are assigned to a fluoride compound (NaMgAlF6H2O).

140

The contents of various minerals in the oil shale samples were determined by XRF.

141

It is noted that XRF actually measures the amount of element in the sample and the

142

data are usually presented in the form of oxides. The results shown in Table 2 indicate

143

that the minerals in HDOS are dominated by Si and Al elements with minor Fe, Ca,

144

K, Ti, Mg Na and Mn. According to the XRD results, the first two minerals in amount

145

should be quartz and kaolinite. The contents of Fe, Ca, K, Na, Mn are obviously

146

decreased after the HCl treatment. This observation is consistent with the ICP analysis

147

to the HCl-washing filtrate which indicates the presence of metal elements in the

148

order of Ca > Fe > K > Na > Mn. The Ca is mainly from calcite and the Fe is from

149

hematite in oil shale as evidenced by the XRD results. The elements K, Na and Mn

150

should be from their carbonates since HCl mainly dissolves these substances.17,18 It is

151

notable that these substances are too little to be detected by XRD. The contents of Si

152

and Al are significantly decreased and those of Ca Ti, Mg and Na are further

153

decreased after the subsequent HCl+HF treatment. The phenomena except Ti are 7


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

Page 8 of 35

154

consistent with the XRD results. The Ti compound in minerals cannot be dissolved by

155

HCl but by the HCl+HF mixture, suggesting that it is probably TiO2 as reported in

156

literatures.10,18 Based on the above discussion, eight minerals (CaCO3, K2CO3,

157

Na2CO3, MnCO3, kaolinite, montmorillonite, Fe2O3 and TiO2) are selected as model

158

substances for the pyrolysis study. For clarity, the minerals are classified into three

159

types: carbonates, clay minerals and metal oxides.

160

3.2 Pyrolysis of organic matter in the presence of carbonates

161

Effects of minerals on the organic matter pyrolysis are discussed from the

162

viewpoints of mass loss (i.e. decomposition of organic matter) and light volatile

163

products (i.e. volatile reaction). Since some minerals may cause mass loss due to

164

self-decomposition, all the model substances were heated individually under the same

165

conditions as those of pyrolysis, along with the individual pyrolysis of organic matter

166

for comparison. Based on the individual results, the theoretical mass loss and release

167

of light volatile products during co-pyrolysis of organic matter with each mineral

168

were calculated via Eq. (1).

169

Eq. (1)

𝑌T = 𝑌M × 𝑤M + 𝑌O × 𝑤O

170

YT is the theoretical value, YM is the experimental data of one mineral during

171

individual pyrolysis, wM is the mass ratio of the mineral during co-pyrolysis, and YO

172

and wO are those of organic matter, respectively. According to the differences

173

between the experimental and theoretical results, mutual influences between minerals

174

and organic matter were evaluated.

175

3.2.1 Co-pyrolysis of organic matter and calcium carbonate 8


Page 9 of 35 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

176

The TG/DTG and MS results collected during individual pyrolysis of HDOS-CF

177

are shown in Figure 2. The DTG curve indicates that the main pyrolysis reaction starts

178

at 400 °C and peaks at 465 °C. MS results indicate that the detectible light volatiles

179

include CH4, C2H6, C3H8, C4H10, C6H6 (benzene), C7H8 (toluene), C6H6O (phenol),

180

H2, H2O, CO and CO2 with mass-to-charge ratios (m/z) of 15, 27, 29, 43, 78, 91, 94,

181

2, 18, 28 and 44, respectively.

182

Figure 3 shows the experimental and theoretical results of TG/DTG and light

183

volatile products during co-pyrolysis of HDOS-CF and CaCO3. It is noted that all the

184

theoretical curves are suffixed with –t. The experimental TG curve (solid line)

185

overlaps with the theoretical one (dotted line) before 500 °C and splits gradually after

186

then, which is accompanied by a higher experimental mass loss rate after 500 °C (see

187

DTG curves). MS results indicate that the amounts of all the light volatile products

188

approximate their theoretical values except that the amount of CO2 formed in the

189

experiment is clearly more than the theoretical value after 270 °C. Figure 2 indicates

190

that HDOS-CF releases CO2 at 200-600 °C which is attributed to the cracking of

191

carboxyl functional group in organic matter.19,20 Individual pyrolysis of CaCO3

192

(Figure S1 in the supporting information) indicates that the pure CaCO3 cannot

193

decompose in this temperature range as expectation. There are two possible reasons

194

for more CO2 release: CaCO3 promotes the cracking of carboxyl functional group in

195

organic matter;21 the organic matter or pyrolysis products promote(s) a small amount

196

of CaCO3 to produce CO2. XRD result of the solid co-pyrolysis product (Figure S2 in

197

the supporting information) indicates formation of a small amount of CaO. The more 9


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

Page 10 of 35

198

CO2 release at temperatures lower than 500 °C is probably attributed to the first

199

reason while the more CO2 release at temperatures higher than 500 °C and the peak at

200

550 °C are probably attributed to the second reason because the carboxyl in

201

HDOS-CF is not very much22, 23 and reported to decompose at lower temperatures.24

202

The above discussion and the results of organic volatile products indicate that CaCO3

203

has little influence on the decomposition of organic matter and volatiles reaction. This

204

finding is different from the literature work which showed a promoting effect by

205

comparing raw and demineralized oil shale. 6,7,25 It is also different from Hu’s work at

206

a lower pyrolysis temperature (520 °C) which showed a negative effect by adding a

207

large amount of CaCO3 into kerogen (9:1 in mass).

208

amount of CaCO3 in Hu’s work led to a long residence time and thus severe

209

condensation of volatiles to form coke which results in an observed mass increase.

210

3.2.2 Co-pyrolysis of organic matter and alkali metal carbonates

11

It is possible that the large

211


212

volatile products during co-pyrolysis of HDOS-CF and K2CO3. The TG curves

213

roughly overlap with each other, the experimental mass loss rate (DTG) is slightly

214

higher than the theoretical value after 510 °C, and the amount of CO2 generated in the

215

experiment is clearly more than the theoretical value. XRD result of the pyrolysis

216

solid product indicates formation of K2O (Figure S2), although the pure K2CO3 is

217

difficult to decompose at 600 °C. This phenomenon is similar to that of CaCO3 and is

218

frequently mistaken as the promoting effect of alkali metal carbonates on organic

219

matter pyrolysis. 6,25 10


Page 11 of 35 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

220

MS results indicate that all the organic volatiles generated during co-pyrolysis are

221

more than the theoretical values except that the CH4 release after 510 °C is less than

222

the theoretical. For clarity, the differences between the experimental and theoretical

223

amounts of light volatile products were quantified according to the literatures 26,27 and

224

the results are shown in Table 3. To understand the influence of K2CO3 on volatiles

225

reaction in detail, generation of the organic volatiles during pyrolysis of fossil fuels

226

was reviewed. CH4 is mainly attributed to the cracking of the end of Cal-CH3 and

227

Cal/Car-O-CH3 at relatively low temperatures and to the cracking of Car-CH3 at high

228

temperatures.28 C2-C4 hydrocarbons are mainly attributed to the cracking of the β site

229

of alkyl side chain and methylene bridge linking aromatic rings, which is

230

accompanied by the formation of C7H8.29,30 C2-C4 hydrocarbons can also be

231

attributed to the cracking of long-chain aliphatic hydrocarbons (the primary pyrolysis

232

products).29 C6H6O is mainly attributed to the cracking of Car-O-Cal29,30 and C6H6 may

233

be generated by dehydrocyclization of long-chain aliphatic hydrocarbons and

234

hydrogenation of phenyl-substituted compounds.31 The H2 release is mainly attributed

235

to the dehydrogenation of aliphatic hydrocarbons at low temperatures and

236

polycondensation of aromatic compounds at higher temperatures.32 The difference

237

between the experimental and theoretical amounts of light volatile products in Table 3

238

indicate that K2CO3 or its derivative lowers the cleavage temperature of Car-CH3

239

bond, promotes the cracking, dehydrogenation and dehydrocyclization of aliphatic

240

chain or hydrocarbons.

241

Figure 5 shows the experimental and theoretical results of TG/DTG and light 11


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

242

volatile products during co-pyrolysis of HDOS-CF and Na2CO3. The TG/DTG and

243

CO2 release results indicate that Na2CO3, similar to K2CO3, has little effect on the

244

decomposition of organic matter. MS results of organic volatile products indicate a

245

slight effect of Na2CO3 on volatiles reaction. The experimental and theoretical

246

differences of C2-C4 hydrocarbons, H2 and C6H6 in Table 3 indicate that Na2CO3

247

promotes the cracking and dehydrocyclization of aliphatic hydrocarbons but the

248

promoting extent is less than that of K2CO3.

249

3.2.3 Co-pyrolysis of organic matter and manganese carbonate

250


251

volatile products during co-pyrolysis of HDOS-CF and MnCO3. The DTG curve of

252

the experiment is obviously different from the theoretical one. It has shown that the

253

peak at 465 °C is attributed to the decomposition of organic matter (Figure 2). The

254

individual pyrolysis of MnCO3 (Figure S5) indicates that MnCO3 decomposition

255

yields a peak at 425 °C. In the co-pyrolysis process, the decomposition peak of

256

organic matter overlaps with the theoretical one while the decomposition peak of

257

MnCO3 moves to 380 and 410 °C. These phenomena indicate that the organic matter

258

or pyrolysis products promote(s) MnCO3 decomposition while MnCO3 (or MnO) has

259

little effect on the decomposition of organic matter. The MS results of organic volatile

260

products indicate that MnO has a slight influence on the volatiles reaction, and the

261

data in Table 3 indicate that the effect of MnO is the weakest in comparison with

262

K2CO3 and Na2CO3.

263

3.3 Mutual influences between organic matter and clay minerals 12


Page 12 of 35

Page 13 of 35 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

264

The clay minerals in Huadian oil shale are mainly kaolinite and montmorillonite.

265

Kaolinite is rich in crystal water and the individual pyrolysis of kaolinite (Figure S6)

266

indicates that the H2O release starts at 430 °C and peaks at about 525 °C. Figure 7

267

shows the experimental and theoretical curves of TG/DTG and light volatile products

268

during co-pyrolysis of HDOS-CF and kaolinite. The H2O release is clearly inhibited

269

and postponed to higher temperatures during co-pyrolysis, suggesting that the

270

pyrolysis products of organic matter inhibit the dehydration of kaolinite. The change

271

in H2O release from kaolinite accounts for the change in the DTG curve and results in

272

the less mass loss. These information further indicates that kaolinite has little effect on

273

the pyrolysis of organic matter, as reported by Hu et al.11 The experimental results of

274

all the organic volatiles are identical to the theoretical results, suggesting that the

275

kaolinite has little effect on the volatiles reaction.

276


277

volatile products during co-pyrolysis of HDOS-CF and montmorillonite. It can be

278

seen that the experimental mass loss is less than the theoretical value while the

279

experimental volatile products is equal to or more than the theoretical value. These

280

phenomena suggest that montmorillonite may promote the reaction of organic

281

volatiles (likely heavy fraction) to form coke and light volatiles, as deduced from

282

demineralization experiment.10 This result is contrary to the report of Hu et al.11

283

(addition of montmorillonite yielded more oil and gas and less coke by an aluminum

284

retort), which cannot be explained and needs a further study. In detail, CH4 and H2

285

releases during co-pyrolysis roughly overlap with the theoretical releases, suggesting 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

286

that montmorillonite has little effect on the dehydrogenation of aliphatic chain or

287

hydrocarbons. Co-pyrolysis yielded more C2-C4 hydrocarbons, aromatic compounds

288

and CO2 at temperatures lower than 450 °C, in comparison with the theoretical values,

289

indicating that the promoting effect of montmorillonite on the reaction of organic

290

volatiles starts at lower temperatures. This observation is consistent with the

291

experimental phenomenon reported by Borrego et al.33

292

3.4 Effects of metal oxides on pyrolysis of organic matter

293

The oxides detectible in Huadian oil shale are Fe2O3 and TiO2. Figure 9 shows the

294

experimental and theoretical results of TG/DTG and light volatile products during

295

co-pyrolysis of HDOS-CF and Fe2O3. It can be seen from the DTG curves that the

296

experimental mass loss rate is larger than the theoretical value at 375-440 °C, equal to

297

the theoretical value at 440-455 °C, and smaller at 455-510 °C. The overall result is

298

that Fe2O3 slightly increases the yield of solid product, which is consistent with the

299

report of Lai et al.13 However, the amounts of the organic volatile products except

300

CH4 generated in the experiment are similar to or larger than the theoretical

301

counterparts. This information suggests that Fe2O3, similar to montmorillonite, also

302

promotes the reaction of heavy organic volatiles to form coke and light volatile such

303

as C6H6, C7H8 and H2. The experimental curves of C2-C4 hydrocarbons, C6H6O

304

overlap with their theoretical curves, indicating that Fe2O3 has little effect on the

305

cracking of long-chain aliphatic hydrocarbons and Car-O-Cal.

306


307

volatile products during co-pyrolysis of HDOS-CF and TiO2. It is clear that all the 14


Page 14 of 35

Page 15 of 35 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

308

experimental curves overlap with the theoretical counterparts, indicating that TiO2 has

309

little effect on the pyrolysis of organic matter in oil shale.

310

4. Conclusions

311

Effects of carbonates, clay minerals, Fe2O3 and TiO2 on pyrolysis of oil shale’s

312

organic matter were investigated by addition of these minerals into HCl-HF treated

313

Huadian oil shale on TG-MS. The TG result represents the decomposition of organic

314

matter and the MS result represents the volatiles reaction. It is found that the organic

315

matter or pyrolysis products delayed the release of crystal water in kaolinite. All

316

mineral compounds investigated show little influence on the decomposition of organic

317

matter but different effects on the volatiles reaction. In particular, CaCO3, kaolinite

318

and TiO2 have little effect on the volatiles reaction while K2CO3, Na2CO3 and MnCO3

319

promotes the volatiles reaction, including cracking of Cal-Cal bond in alkyl side chain

320

or methylene bridge to yield more C1-C4 hydrocarbons and toluene, and

321

dehydrocyclization of long-chain aliphatic hydrocarbons to form benzene and H2. The

322

effects of carbonates follow the order of K2CO3 > Na2CO3 > MnCO3.

323

Montmorillonite and Fe2O3 promote the condensation of volatiles to form coke and

324

C6H6, C7H8 and H2.

325

Acknowledgment

326

The authors gratefully acknowledge the financial support from the National Basic

327

Research Program of China (2014CB744301).

328

Appendix A. Supplementary material

329

Supplementary data associated with this article can be found, in the online 15


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

330

version, at

331 332

References

333

[1] Qian, J.; Wang, J. Oil shale: Alternative Energy for Petroleum. China

334 335 336 337 338 339

Petrochemical Press, Beijing, 2008. [2] Patterson, J. H. A review of the effects of minerals in processing of Australian oil shales. Fuel 1994, 73 (3), 321-327. [3] Espitalie, J.; Makadi, K.S.; Trichet, J. Role of the mineral matrix during kerogen pyrolysis. Org. Geochem. 1984, 6, 365-382. [4] Yan, J.; Jiang, X.; Han, X.; Liu, J. A TG–FTIR investigation to the catalytic

340

effect of mineral matrix in oil shale on the pyrolysis and combustion of kerogen.

341

Fuel 2013, 104, 307-317.

342

[5] Aboulkas, A.; Harfi, E. Study of the kinetics and mechanism of thermal

343

decomposition of Moroccan Tarfaya oil shale and its kerogen. Oil Shale 2008, 25,

344

426-443.

345

[6] Karabakan, A.; Yürüm, Y. Effect of the mineral matrix in the reactions of oil

346

shales: 1. Pyrolysis reactions of Turkish Göynük and US Green River oil shales.

347

Fuel 1998, 77 (12), 1303-1309.

348

[7] Ballice, L. Effect of demineralization on yield and composition of the volatile

349

products evolved from temperature-programmed pyrolysis of Beypazari (Turkey)

350

oil shale. Fuel Process. Technol. 2005, 86 (6), 673-690.

351

[8] Al-Harahsheh, A.; Al-Harahsheh, M.; Al-Otoom, A.; Allawzl, M. Effect of 16


Page 16 of 35

Page 17 of 35 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

352

demineralization of EI-Iajjun Jordanian oil shale on oil yield. Fuel Process.

353

Technol. 2009, 90 (6), 818-824.

354

[9] Chang, Z.; Chu, M.; Zhang, C.; Bai, S.; Lin, H.; Ma, L. Influence of inherent

355

mineral matrix on the product yield and characterization from Huadian oil shale

356

pyrolysis. J. Anal. Appl. Pyrolysis 2018, 130, 269-276.

357

[10]Zhao, X.; Zhang, X.; Liu, Q.; Lu, Z.; Liu, Z. Organic matter in Yilan oil shale:

358

characterization and pyrolysis with or without inorganic minerals. Energy Fuels

359

2017, 31, 3784-3792.

360

[11]Hu, M.; Cheng, Z.; Zhang, M.; Liu, M.; Song, L.; Zhang, Y.; Li, J. Effect of

361

calcite, kaolinite, gypsum, and montmorillonite on Huadian oil shale kerogen

362

Pyrolysis. Energy Fuels 2014, 28 (3), 1860-1867.

363

[12]Wood, D. A.; Hazra, B. Characterization of organic-rich shales for petroleum

364

exploration & exploitation: A review-part 2: Geochemistry, thermal maturity,

365

isotopes and biomarkers. J. Earth Sci. 2017, 28 (5), 758-778.

366 367

[13]Lai, D.; Chen, Z.; Lin, L.; et al. Secondary cracking and upgrading of shale oil from pyrolyzing oil shale over shale ash. Energy Fuels 2015, 29 (4), 2219-2226.

368

[14]Huhn, F.; Klein, J.; Juntgen, H. Investigations on the alkali-catalysed steam

369

gasification of coal: Kinetics and interactions of alkali catalyst with carbon. Fuel

370

1983, 62, 196-199.

371

[15]Guo, S.; Jiang, Y.; Liu, T.; Zhao, J.; Huang, J.; Fang, Y. Investigations on

372

interactions between sodium species and coal char by thermogravimetric analysis.

373

Fuel 2018, 214, 561-568. 17


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

374 375

Page 18 of 35

[16]Saxby, J.D. Isolation of kerogen in sediments by chemical methods. Chem. Geol. 1970, 6, 173-184.

376

[17]Burnham, A.K. Chemistry and kinetics of oil shale retorting. Oil shale: A solution

377

to the liquid fuel dilemma, American Chemical Society, Washington DC, 2010

378

(Chapter 6).

379 380 381 382

[18]Totten, M.W.; Hanan, M.A. Chapter 12 Heavy minerals in shales. Developments in Sedimentology 2007, 58, 323-341. [19]Wang, M.; Li, Z.; Huang, W.; Yang, J.; Xue, H. Coal pyrolysis characteristics by TG-MS and its late gas generation potential. Fuel 2015, 156, 243-253.

383

[20]Arenillas, A.; Rubiera, F.; Pis, J.J. Simultaneous thermogravimetric-mass

384

spectrometric study on the pyrolysis behaviour of different rank coals. J. Anal.

385

Appl. Pyrolysis 1999, 50, 31-46.

386

[21]Cypre, R.; Furfari, S. Hydropyrolysis of high-sulphur-high-calcite Italian Sulcis

387

coal. 1. Hydropyrolysis yields and catalytic effect of the calcite. Fuel 1982, 61,

388

447-452.

389

[22]Zhao, X.; Liu, Z.; Lu, Z.; Shi, L.; Liu, Q. A study on average molecular structure

390

of eight oil shale organic matters and radical information during pyrolysis. Fuel

391

2018, 219, 399-405.

392

[23]Tong, J.; Han, X.; Wang, S.; Jiang, X. Evaluation of structural characteristics of

393

Huadian oil shale kerogen using direct techniques (solid-state

394

FT-IR, and XRD). Energy Fuels 2011, 25, 4006-4013.

395

13C

NMR, XPS,

[24]Han, F.; Meng, A.; Li, Q.; Zhang, Y. Thermal decomposition and evolved gas 18


Page 19 of 35 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

396

analysis (TG-MS) of lignite coals from Southwest China. J. Energy Inst. 2016, 89,

397

94-100.

398

[25]Guo, H.; Lin, J.; Yang, Y.; Liu, Y. Effect of minerals on the self-heating retorting

399

of oil shale: Self-heating effect and shale-oil production. Fuel 2014, 118,

400

186-193.

401 402 403

[26]Tiwari, P.; Deo, M. Compositional and kinetic analysis of oil shale pyrolysis using TGA-MS. Fuel 2012, 94, 333-341. [27]Pan, L.; Dai, F.; Huang, J.; Liu, S.; Li, G. Study of the effect of mineral matter on

404

the thermal decomposition of Jimsar oil shale using TG-MS. Thermochim. Acta

405

2016, 31-38, 627-629.

406

[28]Shi, L.; Liu Q.; Zhou, B.; et al. Interpretation of methane and hydrogen evolution

407

in coal pyrolysis from the bond cleavage perspective. Energy Fuels 2017, 31,

408

429-437.

409

[29]Lin, L.; Lai, D.; Guo, E.; Zhang, C.; Xu, G. Oil shale pyrolysis in indirectly

410

heated fixed bed with metallic plates of heating enhancement. Fuel 2016, 163,

411

48-55.

412 413 414

[30]Porada, S. The reactions of formation of selected gas products during coal pyrolysis. Fuel 2004, 83, 1191-1196. [31]Piroska, S.; Gabor, V.; Ferenc, T.; Tamas, S. Investigation of subbituminous

415

coals by thermogravimetry-mass spectrometry: Part 1. Formation of hydrocarbon

416

products. Thermochim. Acta 1990, 170, 167-177.

417

[32]Lu, Z.; Feng, M.; Liu, Z.; Zhang, X.; Liu, Q. Structure and pyrolysis behavior of 19


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

418

the organic matter in two fractions of Yilan oil shale. J. Anal. Appl. Pyrolysis

419

2017, 127, 203-210.

420

[33]Borrego, A.G.; Prado, J.G.; Fuente, E.; Guillen, M.D.; Blanco, C.G. Pyrolytic

421

behavior of Spanish oil shales and their kerogens. J. Anal. Appl. Pyrolysis 2000,

422

56, 1-21.

423

20


Page 20 of 35

Page 21 of 35 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

424

Table captions

425

Table 1. Proximate and ultimate analyses of the raw and demineralized oil shale

426

samples

427

Table 2. The contents of main minerals in the raw and demineralized oil shale

428

samples

429

Table 3. The differences between the experimental and theoretical amounts of light

430

volatile products generated by co-pyrolysis of HDOS-CF and carbonates

431

21


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

432

Figure captions

433

Figure 1. XRD patterns of the raw and demineralized oil shale samples.

434

Figure 2. Results of TG/DTG and light volatile products detected by MS during

435

pyrolysis of HCl-HF treated Huadian oil shale (HDOS-CF).

436

Figure 3. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG

437

and light volatile products during co-pyrolysis of HDOS-CF and CaCO3.

438


439

and light volatile products during co-pyrolysis of HDOS-CF and K2CO3.

440


441

and light volatile products during co-pyrolysis of HDOS-CF and Na2CO3.

442


443

and light volatile products during co-pyrolysis of HDOS-CF and MnCO3.

444


445

and light volatile products during co-pyrolysis of HDOS-CF and kaolinite.

446


447

and light volatile products during co-pyrolysis of HDOS-CF and montmorillonite.

448


449

and light volatile products during co-pyrolysis of HDOS-CF and Fe2O3.

450


451

and light volatile products during co-pyrolysis of HDOS-CF and TiO2.

22


Page 22 of 35

Page 23 of 35 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

453

Table 1. Proximate and ultimate analyses of the raw and demineralized oil shale

454

samples

455

Sample

Mad

Aad

Vad

FCad

Cdaf

Hdaf

Ndaf

O*

Sorg, daf

H/C

HDOS

2.83

70.27

22.30

4.51

60.16

8.13

1.44

30.03

0.24

1.62

HDOS-CF

1.20

15.65

60.85

22.30

66.96

8.03

1.7

20.81

2.50

1.44

*

by difference

23


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

Page 24 of 35

456

Table 2. The contents of main minerals in the raw and demineralized oil shale

457

samples Mineral content (wt.%) Sample SiO2

Al2O3

Fe2O3

SO3

CaO

K2O

TiO2

MgO

Na2O

MnO

HDOS

36.07

18.09

3.13

5.03

3.30

1.47

1.16

0.39

0.73

0.14

HDOS-C

35.16

17.74

1.94

4.77

0.31

0.11

1.13

0.33

0.34

0

HDOS-CF

0.68

0.81

1.61

4.58

0.15

0.13

0.55

0.09

0.01

0

458

24


Page 25 of 35 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

459

Table 3. The differences between the experimental and theoretical amounts of light

460

volatile products generated by co-pyrolysis of HDOS-CF and carbonates CH4

C2-C4

C6H6

C7H8

C6H6O

H2

(×10-4)

(×10-4)

(×10-4)

(×10-5)

(×10-5)

(×10-3)

CaCO3

0.10

0.20

0.12

0.04

0.03

0.02

K2CO3

-0.95

2.31

1.01

1.44

0.13

1.72

Na2CO3

-0.21

2.02

0.41

0.57

0.02

0.80

MnCO3

-0.40

1.10

0.38

0.61

0.05

0.32

Minerals

461 462

25


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

463

464 465 466 467

Figure 1. XRD patterns of the raw and demineralized oil shale samples. (Q: quartz; K: kaolinite; M: montmorillonite; C: calcite; H: hematite; P: pyrite; N: NaMgAlF6H2O)

468

26


Page 26 of 35

Page 27 of 35 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

469 470 471

Figure 2. Results of TG/DTG and light volatile products detected by MS during pyrolysis of HCl-HF treated Huadian oil shale (HDOS-CF).

472

27


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

473 474 475

Figure 3. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and CaCO3.

476

28


Page 28 of 35

Page 29 of 35 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

477 478

Figure 4. Experimental (solid lines) and theoretical (dotted lines) results of

479

TG/DTG and light volatile products during co-pyrolysis HDOS-CF and K2CO3.

480

29


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

481 482 483

Figure 5. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and Na2CO3.

484

30


Page 30 of 35

Page 31 of 35 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

485 486 487

Figure 6. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and MnCO3.

488

31


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

489

490 491 492

Figure 7. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and kaolinite.

493

32


Page 32 of 35

Page 33 of 35 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

494 495

Figure 8. Experimental (solid lines) and theoretical (dotted lines) results of

496

TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and

497

montmorillonite.

498

33


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

499 500 501

Figure 9. Experimental (solid lines) and theoretical (dotted lines) results of TG/DTG and light volatile products during co-pyrolysis of HDOS-CF and Fe2O3.

502

34


Page 34 of 35

Page 35 of 35 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

503 504


505

and light volatile products during co-pyrolysis of HDOS-CF and TiO2.

35


Mutual Influences between Organic Matter and Minerals during Oil

Recommend Documents