Hydroxyl contents of coals: new data and statistical analyses

o(116.70x7,79 0301.O?XlSO2.00 0

Hydroxyl contents of coals: new data and statistical analyses RICHARL) F. YARZAK ZEINAI~ABDIIL-BASETand PETER H. GIVEN College of Earth and Mineral Saences. Pennsylvania State University. University Park. PA 1680’. li.S.4.

Abstract-Data previously published for the phenolic hydroxyl content of 35 coals have been supplemented b) the study of a further 17 samples. Various statistical analyses have noti’ been made of the relationship of the data for the full set of 52 samples to other properties of the coals. Hydroxyl contents can be expressed either as fractions of total organic matter or of the total organic oxygen In the coals. Data expressed on the first of these bases exhibit a strong dependence on the degree of metamorphism of the coals. while those on the second basis do not. Statistical correlations on either basis show that systematic relations between coal properties diRer for different coal provinces of the U.S.A.. thus demonstrating that the properties of a coal are dependent to an important extent on the geology and geochemistry of the basin in which it is found.

INTRODUCTION Wr HAW reported previously the hydroxyl content of 35 U.S. coals and discussed correlation of the results with other coal properties (ABDEL-BASETer ul.. 1978). We present data here for another 17 coals. and have applied more sophisticated statistical analyses than before to the results for the full set of 52 coals. Coals differ from other concentrations of organic matter in the Earth’s crust in having relatively high concentrations of oxygen (up to 19”,, of total organic matter in the coals studied here. and up to X’,, or so in iignites). It is known from previous work that phenolic hydroxyl is a major form of occurrence of this oxygen. and therefore the content of these groups in coals is of some interest in its own right in describing the chemical constitution of coals. However. the coals of the U.S. contain a very diverse set of materials of differing geological ages. environments of deposition and conditions of metamorphism (or catagenesis). According&. the principal objective of this stud) was to determine whether an important structural characteristic of a coal varied according to its geological antecedents. and whether the systematic trends in the chemical structure of coals are dependent upon geological history. as roughly characterized b> assignment of a sample to a geological province. EXPERIMENTAL The hydroxyl contents of the new coals were determined b! acetylation with “‘C-lahelied acetic anhvdride. as described previously (ABIJEL-BASI~T cr ul., 1978): It was found that the precision of a determination (+2 standard deviatlons) is 0.1. The procedure for obtaining by difference the organic oxygen contents of the coals was also discussed earlier. The coals are identified by sampling site and some ke, properties in the Appendix. The statistical procedures used were standard and are to be found in well known texts. such as that by NETERand WASSERMAN (1974). In the selection of samples for study, coals of medium and low voltatile bituminous classes in the ASTM system. and anthracite. were rejected on the grounds that their

hydroxyl contents are already known to be ver] small or zero (for references. see previous paper. AHIILL-BASI.T01 al.. 1978). Lignites were excluded because their chemical characteristics seem to be sufficientI> different from those of coals of higher rank as to make them a separate population. and also determination of their total oxygen contents presents problems that are sui ycw,ri.s. The samples studied still cover a wide range of degree of metamorphism. covering subbituminous coals and coals of the high volatile bttuminous C. B and A classes of the ASTM system (i.e. about 74-881,, C. dmmf. or reflectance values for vitrinite from about 0.35 to l.l”,). Within these limitations. the samples were selected to give approximately equal representation to coals of the Eastern. Interior. and Great Plains + Rock? Mountain provinces of the U.S.A. RESULTS AND DISCUSSION Figures for the content of an oxygen functional group can be expressed in several ways. We have used two (“,, 0 as OH)/(coal organic matter). and (Y,, 0 as OH),(total organic oxygen content). The previous work showed that these quantities exhibit different relationships with other coal properties, and they are considered separately here. One might expect diverse sets of geological conditions operating for varying lengths of time on the metamorphism of diverse assemblies of plant debris to produce a heterogeneous series of coals. Therefore one might predict that no one coal property used as a numerical measure of the degree of metamorphism could adequately fulfil its function. Accordingly. ten coal properties were made available to the computer in performing regression analyses. six of which are strong functions of the degree of metamorphism. The other properties (content of mineral matter. nitrogen, organic suiphur. and of vitrinite + pseudovitrinite macerals) are not systematic functions of the degree of metamorphism. but for various reasons were thought worthy to be included in the analysis. A principal components analysis followed by Varimax rotation revealed that five components explained 957; of the variance in the

R. F.

282

YARZAH. Z.

A~~EL-BAFI.Tand P. H. GIWN

matrix composed of the ten coal properties selected: the six variables measuring the degree of metamorphism loaded strongly together. with the other four variables each loading on separate factors. The following list serves both to show the variables mcluded in the analyses and to define the symbols used beiow in equations and tables. organic carbon content. dry mineral-matterfree basis (dmmn 0 organic oxygen content, dmmf H/C atomic ratio in organic matter atomic ratio in organic matter OKCf caloritic value. dmmf (b.t.u./lb.) log Ro logarithm of mean maximum reflectance of vitrinite under oil immersion per cent of mineral matter in dry coal .%IA4 v nitrogen content. dmmf content of organic sulphur. dmmf SO vitrinite + pseudovitrinite. content of V volume “,,. mineral-matter-free 0H;coul 0 as OH, per cent of dry mineral-matterfree coal 0 as OH, per cent of total organic oxygen. OH!0 C

The distribution of most of the rank parameters for the set of coals studied is approximately normal. However. the distribution of reflectance values is closer to log normal. which is why the logarithm of the reflectance appears in the above list. 6.50

I. Corrrlakm

wih

OH/coal

Correlations of OH/coal for the set of 52 coals with the six rank parameters taken singly are. on the whole. excellent. The correlation coefficients are:

c

-0.91

CV

-0.86 0

O!C

0.85 log R. 0.85 HIC

-0.s 0.57

It follows that the rank parameters correlate reasonably well with each other. and that OH~e~ui is itself a rank parameter. A regression of the hydroxyl content with the carbon content yields: OH~cou~ = -0.299 C + '9.0.

(1,

of OH/coal against C is shown in Fig. I. where the line I represents eqn (I 1. The standard error of the OH content estimated from the equation is 0.44. and the standard deviation of the coefficient of C is 0.019. The variance explained (R')is 8X1”,, (all values for R' in this paper have been adjusted to take account of differences in the number of parameters A plot

in the equation of samples).

under consideration

Entry

of additional

and the number

variables

improves

R' only marginally.

Thus. a regression equation in C and .SOincreases the adjusted R2 to 85.3”;,, and one in C and log R. improves it to 85.2”,. The

previous

coals yielded

multiple

regression

analysis

in C. R. and

b’. it was

noted that two parameters

were evidently

needed to

7

5.90 I1.30

I4.7c

z I; 4.10 E -0 : 3.sIg :

I2.9c

0

A, cools of Eastern proumce I2.3c

1 7cI-

6, lntermr

province

C, western

provinces

1 1cI03 I -_ 72.0

74.0

76.0

78.0

for 35

an equation

84.0 80.0 82.0 CarbonContent, ‘e (dmmf)

86.0

88.0

90.0

92.0

Fig. I. Hydroxyl contents ol coals (OH/coal) as a function of carbon content. 1. single regression for whole set: II and 111.regressions for coals of Eastern + Interior Provinces. and western provinces. respectively.

Hydroxyl contents of coals define rank. and that a dependence on vitrinite content was to be expected since the hydroxyl content of other macerals was known to be appreciably less (GIVLN 1’1 al.. 1960. 1965). While the entry of reflectance is still warranted. a more useful and significant variable will be developed instead: the previous marginal correlation with vitrimte has not been sustained with the addition of more data. The samples studied were from the Eastern Province (Carboniferous). the Interior Province (also Carboniferous). or from the Rocky Moutain and Great Plains Provinces (designated here as ‘western’; Cretaceous). The correlations of OH:coul with coal properties noted above hold for the coals of the various provinces considered separately. as the following correlation coefficients show:

c Cl o<

However. examination of the residuals (observed OHl’coul- predicted OH!coal) from eqn (I ) revealed marked differences between the subsets from different provinces: PKl\lllCC EaSlCm lnlrrlor W?SlMl

Meiln rwdu.tl

No

of rn,dualr

- 00I -0 1.l -029

> 0

No. ol residuals < 0

12 15 5

6 I 13

Regression equations were developed for OHjcoal and C for each province separately. An F-test at the 0.95 level (i.e. a formal test of the equivalence of the regression lines) showed that the three separate regressions did explain significantly more variance than the single regression for the whole set. This procedure is not entirely satisfactory. because the statistical analysis is applied to rather small subsets. Therefore. a procedure was adopted that allows the whole set to be treated together, while still allowing differentiation between provinces. In this the stepwise regression uses indicator variables as follows:

+ BlXl + B;x;

XL XE X] x;

= = = =

represent

1 for Interior 1 for western “/i carbon for “, carbon for

numerical

(2)

coefficients.

coals. zero for others coals, zero for others Interior coals, zero for others western coals, zero for others.

In effect the procedure tests whether the slopes and intercepts of the regression lines are significantly different for the different provinces. Equation (2) for the subsets reduces to the following: Eastern

coals OHicoal = /30 + fi,C

coals OH/ma/

western

= (PO + /lb) + C/?, + PlK

(3)

coals OH/coal = (PO + ff”o,+ (/II + p;,C.

(5)

When the regression was performed it was found that each of the four indicator variables taken singly significantly improved the original equation. The greatest improvement resulted from the entry of 8;;. the intercept term for western coals. The general equation developed was: OHicoal = -0.341 C + 32.67 - 0.59X;.

(3)

(6)

It will be noted that eqn (6) uses only one of the four indicator variables. The variance explained by the use of this equation (R’) is 88.2”,. It implies that coals of the western provinces are a distinct population from those of the Eastern and Interior provinces. A similar equation can be developed. with different coefficients. in which XL appears rather than X;: m this case. the fraction of variance explained is slightly less. at 87.59,. and the distinct population would consist of the coals of the Interior Province. An equation involving both XL and X; leads to the generation of separate correlation lines for coals of each of the three regions. but explains a fraction of the variance only marginally better (89.0?,) than that explained by an equation that contains only one of the X parameters. The conclusion is that it is unclear in this correlation whether the Eastern coals are closer. in OH content. to the coals of the Interior or western provinces. Correlations of the data with oxygen contents are less ambiguous; coals of the Interior Province are clearly a distinct population, while those of the Eastern and western provinces cannot be differentiated. However. oxygen contents are not generally used as rank parameters. In these confusing circumstances. we offer eqns (7a) and (7b) as useful correlations. derived directly from eqn (6): for Eastern

and Interior-OH/coa/

for western-OH/coal

OH/coal = /& + p,C + &XL + B;XE

where the fi symbols and

Interior

283

= 0.341 C + 32.67

(7a)

= -0.341 C + 32.08.

(7b)

The variance explained has already been given; the standard error of the estimate is 0.37. and the standard deviations of the coefficients /Ii and fit are 0.018 and 0.124, respectively. All of these values represent material improvements on those resulting from the use of eqn (1). The lines for provinces marked II and III on Fig. 1 represent piots of eqn (7a) and (7b). A similar approach was made using calorific value as the rank parameter. The general equation developed was: OH/coal = 0.00161 C’V + 28.24 + 0.53X;

- 0.59X;.

(8)

Again, the slopes are essentially the same. but this, time separate intercept terms for both Interior coals

R. F.

284

YAKZAII.

Z. AIUXL-BASI.Tand P. H. GIWN

6.50,

4.701

5 ;

4.10E ‘D % 3.50b0 z5 ;;

2.90”

0

A, cools of Eostarn province 8, Interior province C. western provinces

2.30

, 12500

12900

13300

,

13700

14100

Caiorific Fig. 2.

14500

Value, BTU

14900

15300

15700

f 16100

16500

lb, (dmmf)

Hydroxyl contents of coals (OHMY&) as a function of caioritic values. I. Interior Provtnce samples: Il. Eastern Province samples: III. Samples from western Provinces,

and for western coals are each highly significant when entered into the regression together; the resulting lines are shown in Fig. 2. The variance explained is 87.5’,,, and the standard error of the estimate is 0.38; standard deviations are: fir, 0.00010; X& 0.135; XU,. 0. L63. Thus good correlations have been found for the hydroxyl data with two rank parameters tested separately. This fact shows why adding a second parameter to either equation has little effect in increasing the variance explained. No significant correlations emerged when the other coal properties. which are not rank parameters. were entered. 2. Corrrlatior~s wirh OH/O A plot of OHiO against the carbon content for the first set of 35 coals was presented in the earlier paper (ABDEL-BASEI cr al.. 1978). It showed a great deal of scatter; addition of points for the additional 17 coals increases the scatter (see Fig. 3). Correlation coefficients for OHIO for the full set of 52 coals are: 0. -0.7 I : Cv. i-0.67: C. ~0.62. That is. there is a significant tendency for OH/O to increase with increasing rank. and correspondingly for the total content of other forms of oxygen functional groups. expressed in a similar way. to decrease. Inspection of Ihe ptots showed that the point for the one coal of medium volatile bituminous rank in the set was a bad outlier, and it was discarded from further analyses. At this level of rank. small errors

m either the hydroxyl determination or the oxygenby-difference can have a large effect on the value of the ratio. Also. in these analyses there is a statistical

requirement of bivariate normality: the outlying point will have an unduly large effect on the regressions since it is outside our basic sample space. With this point discarded. the correlation coefficients rise to: 0. -0.78: CV. +0.72: C. +0.70 (i.e. RZ values of 0.61. 0.52 and 0.49. respectively). A regression of OH/O against 0 explained only about 60”; of the variance. increased to Go,, when a term in S, was included. An improvement in the correlation with 0 was noted when the approach using indicator variables was used (R' = 66.9’,,). An Important point demonstrated by this last regression is that coals of the Interior Province have significantly higher OH/O than CodIS of the other provinces at the same level of rank. Visual examination of plots of ON/O against various rank parameters suggested that any correlations might be non-linear. Accordingly, various mathematical functions were tested: x2, l/x. l/x2, e-I and log Y. where .Y= 0. C. O/C. H/C. or CG’.The greatest promise of improved fit was obtained in a regression of OH/O against l/O. the reciprocal of the oxygen content. but even so the adjusted R' was only 61.9”,,. However. a very marked improvement was found when indicator variables were introduced. This introduction led to the following equation: OH;0 = 154.0(1/O) + 25.97 + 8.34X;.

(9)

Hyirox>l

contents

285

of coitk

80.0 A.

75.0 70 0

of Eastern

COOIS

prov,nce

0. Interior

provtnce

c, western

provinces

65 0

0 u g 60.0 % : 5 ::

55.0 50.0

0 45 0 c

40.0 c

c c

c c

c

cc

c

35.0

c

c

c

c A

c

30.0 72.0

74.0

76.0

78.0

80.0

82.0

Carbon Content, Fig. 3. Relationship

between

Here the standard

error of the estimate is 4.39 and deviations are /?i (i.e. 184.0). 15.17: fib (25.97). I .32. The data are plotted in Fig. 4. where the two lines. for Interior and Eastern + western coals. are both shown. It has to be admitted that this correlation is not particularly impressive, and that it is difficult to assign a chemical meaning to the reciprocal of the oxygen content. Nevertheless. it does have enough statistical significance to be taken seriously, and it is undoubtedly an improvement on the non-correlation shown in Fig. 3. Also. the coals of the Interior Province. in this mode of presentation of the data. quite clearly represent a separate population. The lack of distinction between coals of the Eastern and western provinces ma)’ be associated with the fact that there is little overlap in values of l/O for the coals of the two areas.

the variance explained is 78.7’!,,. The standard

SOME GENERAL CONCLUSIONS Direct determinations made

of oxygen

in coals

(INTERNATIONAL ORGANIZATIOK

can be

FOR STAN-

L)ARDIZATION. 1971). but they are of little value unless the coal is first demineralized. because some mineral oxygen reports as organic. For this reason. oxygen is commonly calculated by difference. KINSOK and B~LCHER(1975) state that. if all feasible steps are taken to minimize oxygen-by-difference

interferences is “accurate

by mineral matter. to +0.31,;“. While

OH/O

84.0

86.0

88.0

90.0

92.0

“O (dmmf)

and carbon content.

we certainly took steps to minimize these interferences. we did make some approximations (GIVENand YARZAH.to be published) and so our oxygen contents may not be quite as good as those of Kinson and Belcher. Thus part of the variance not explained bq the correlations of OH/O may be due to errors in the data. Although steps were taken to ensure that the samples studied here were representative splits of the samples on which the ultimate analyses were made. it is always possible that there is a significant sampling error. This would also contribute some noise to the data. Nevertheless. the correlations discussed here are all highly significant in the sense that the probability of there being in fact zero correlation is exceedingly small. It has been seen that the quantity. OH,c~ul. is itself a rank parameter. decreasing with increasing degree of metamorphism. On the other hand. the alternative quantity. OH/O. is a rather poor rank parameter. An obvious implication is that the sum of whatever other oxygen functional groups ma> be present (i.e. O,,,,.,, - O,,.,. representing carbonyl. ether. heterocyclic 0) must also change in a rather random manner with the degree of metamorphism. It can he seen from Fig. 3 that in the range 79-W,, C dmmf. OH.0 for coals from the Interior Province ma> be appreciably greater than the typical values for coals from the and. correspondingl!. ‘other’ western provinces. oxygen wili be less. The oxygen contents of the coals studied here arc in the range 19-Z”,,. or 19X’,, if one excludes the

R. F. YAKZAII. 2. AIWEL-BASETand

286

P.

H.

GIVEN

80.0

65.0 0 ,: 8 d ‘;, 6’ ;

60.0 55.0 50.0

0 45.0 40.0

A,

coals

0,

Internor

of

province

Eastern

C,

western

provinces

pravtnce

35.0 30.0

-I r

(1.050

t

0.075

0.100

0.125 Reciprocal

0.150

0.175

of Oxygen

0.200 Content,

0.225 (1

0.250

0.275

0 300

0%)

Fig. 4. Regressions of OH!0 against 110. I. Interior Province samples: II. Samples from Eastern and western Provinces. one coal of the medium volatile bituminous rank class. Thus oxygen is a quite significant contributor to the composition of the coals and the presence of oxygen-containing functional groups is an important characteristic of their chemical structure. It has been seen that correlations of hydroxyl contents. expressed on one or the other basis. with other properties of coals indicate that the coals of the three provinces constitute at least two distinct populations of materials. However. the various correlations are not completely consistent in defining which provinces should be judged to yield coals belonging to different populations. The consensus is that it is the coals of the Interior Province that are distinctively different. There is of course little overlap in rank between coals of the Eastern and western Provinces; this reflects the character of the coals available. and is not a bias in our selection of samples. Nevertheless. it is quite clear from the findings that the systematic relationships between coal properties are different for different provinces. The coals of the Interior and Eastern Provinces are of Carboniferous age. but whereas the Eastern coals were formed in a geosyncline of classical type. under conditions that were sporadically marine. Interior coals were formed in shallow saline waters and have never been deeply buried. Hence the latter coals tend to be of lower rank than the former and most probably underwent their metamorphism at relatively low temperatures and pressures over a long period.

The western coals are of Cretaceous or early Tertiary age. and were formed from vegetation quite different from that which flourished in the Carboniferous Moreover. they were formed in a large number of relatively small basins: little is known about their conditions of metamorphism except that many of the basins were on the flanks of the Rocky Mountains and the coals were formed shortly before the Laramide orogeny, with which a considerable amount of igneous activity was associated. The conclusion of this study is that these gross differences in paleoenvironments and the geological dilferences have significantly influenced the geochemistry of the coals. leading to the formation of sets of materials having some systematic differences m chemical structure. This conclusion has not. we believe. been established previously. and is Important in demonstrating the need for a ne% classification of coals based on geological and geochemical criteria. The conclusion is supported bq some work to be reported elsewhere (YARZAD and GIVI.~. submitted). in which cluster analysis segregated a set of IO4 U.S. coals into three more homogeneous populations. The coal properties responsible for much of the partitioning of samples into groups were the contents of sulphur and carbon. and the samples in any one group were mostly. though not entirely. from one geological province. and many of the exceptions could be accounted for in terms of the character of the paleoenvironments.

Hydroxy

1contents

Source and characteristics

287

of coals

of coals used 0

PSo( Sample No

Seam and Locarwn

ASTM rank class

Vrtrinilc plus pseudo utrinitc (“,,I

hfmeral matter (“, dry)

Carbon r., dmmn

0 as OH I’,, of dmmf Cwdll

(“.. of lotal 0 dmmn

57 5x 2: 3.1 42 47 28 29 47 34 19 50 17 40 4.0 3x 7.5

49 9 441 54 b 41.2 53.9 51 2 37 2 75 I ?I 7 46 4 442 449 644 53 I 47 I 54 I .‘I 7 74 9

5 .q 41 51 43 49 59 5.1 47 55 5.0 51 41 53 5x 5.2 5.1

53 7 hl 5 s5.3 52 9 4.47 MI 3 609 5X.2 51 9 4x 4 53 4 5hb 59 4 49 9 52 3 52 7

6.5 64 5.5 4.5 IO 47 47 45 64 b4 4.2 53 5.5 50 47 4.3 61 d9

379 T9 3 39 3 401 444 45 b 444 39 1 7i k 35.x 18 I 374 42 3 3? 9 414 42 3 40 5 3b 6

203 212 268 269 276 278 295 301 305 306 307 308 3.26 329 330 331 3% 357

Ohio No. 7. Wellsron. OH Ohio No. 2. Jackson. OH Lyons. Duncnn Gap. VA Imbodcn. Owka. VA Ohm No 8. Cadu. OH Ohm No 9. Cumkrknd. OH Pittsburgh. Thomas PA Splashdam. Huysi. VA Ohm No. I I. Sm~thticld. OH Ohm No. 12. Yorkville. OH Ohm No. IZA. Yorkville. OH Ohm No. 5. Hamden. OH Upper K~t~nnnmg. Adrmn. PA Brookvilk. Edinbure PA Mlddlc Kittanning. >illsville. PA Brookville. Grove Cit). PA Lower Kltlanninn. Brum. PA Lower Elkhorn. Mouthwd. KY

A Coals from the Eastern Provmce HVB 10.9 907 78.3 HVC 3.0 HVA 75.9 5.5 HVA 7.1 79.0 HVA 13.8 80.7 HVA 23.0 77 HVA 12.0 84.0 HVA 6.8 79.7 HVB 27.5 86.2 HVA 33.1 61.9 HVA 21.2 87.0 HVB 13.5 79.8 HVA 21.2 77.0 HVA 21.4 74.9 HVB 8.0 n4.2 HVA 5.8 110.5 HVA IS.0 75.3 HVA 12.3 76.6

79.8 7Y.3 8b.3 86.0 83.5 80.5 84.3 88.2 82.3 83.8 82.3 80.2 85.5 85.0 83.5 84.6 847 87 a

Il.5 13.1 4.7 6.5 7b 91 76

213 215 216 217 219 244 252 272 273 279 280 284 287 288 289 290

Kentucky No. 9. Owensboro. KY Kentucky No. 9. Sturg~s. KY Kentuck) No 14. M~dlsonvllle. KY Kentuck) No. 9. Madisonville. KY Kentucky No. 4. St. Charles. KY Lower Cherokee. Chilbcolhe. IA Illmo~s No. 5. Shuwnaiown. IL Kentucky No. 9. Dmkesboro. KY Kcntuckv No. I I. Driikcsbwo. KY Indiana No. 3. Jwmville. IN Indiana No. 6. Dugger. IN Lower Dekoven. S~onefort. IL Bev~cr. Excello. MO llhnoir No. 6. Victoria. IL Illinois No. 4. Wilmmglon. IL llhnoir No. 4. S. Wilminglon. IL

B Coals from HVB HVA HVB HVB HVB HVC HVA HVB HVB HVB HVC HVA HVB HVC HVB HVB

the lnrermr Il.5 16.2 10.5 21.4 9.8 23.4 15.7 il.9 19.5 22.1 18.3 25. I 17.1 10.7 II.4 IS.9

80.6 83.9 81.3 82.3 82. 78.9 82.3 82. 79.3 80. I 81.6 83.7 82.2 79.6 80.6 81.3

9.9

230 231 233 235 236 237 238 239 241 242 249 310 311 312 313 314 315 316

Rosebud. Colstnp. MT Laramie No. 3. Erie. CO Wndge. Energy. CO Colorado B- -82 Bed. Somerset. CO Colorado Basin 8. Rcdmonc. CO Rock Canyon. Price. UT Utah A. Hiawnthr UT Utah 8. Hiawatha UT Monarch. Sheridan. WY Dletz. Sheridan. WY Rock Canyon. Wellington. UT New Mexico No 7. Fru&md. UT New Mcx~co No. 6. Fruitland. UT Red. Kayema. AZ Hiawatha. Waltis. VT Bhnd Canyon. Huntingdon. UT Wadge. Oak Creek. CO Flrh Creek. Oak Creek. CO

C. Coals lrom SUBBIT B SUBBIT B HVC HVB MED VOL HVB HVA HVA SUBBIT B SUBBIT B HVB HVC HVC HVC HVB HVA HVC

western Provinrrr IO.5 6. I 10.3 8.7 9.1 14.1 IO.8 11.5 8.1 6.7 Ii.3 9. I 20.0 7.1 17.3 II.5 Il.7

I

HVC

Provmce 75.0 86.1 84.0 86.2 84.7 75.0 82. I 82.7 85 7 699 92. I 87.1 71.2 87.7 84.0 82.5

4.9

78.2 76.1 88.8 86.8 92.2 79.9 85.2 83.9 85.7 90.6 70.2 83.5 80.9 85.9 78.9 81.8 876

87.I

I I

76.3 76.6 78.3 81.0 90.4 81.9 80.5 80.3 73.9 744 81.3 77 9 78.9 78.0 80.2 81.5 76 6 78.3

as OH

oxygen (dim (“., dmmn

3.9 9.1 74 a.9 II I 5: 67 8.5 ?5 7.3 41

6.6 9.3 8.2 10.9 97 84 80 105 IO3 96

73 X.8 II 7 9.9 97 I 7.I 16.3 13.9 II.? 2.2 IO.? 10.6 Il.5 19.0 IS.0

I /.I

14.1 I30 14.6 I I.4 10.1 IS.1 13.5

3.h

Ackrlo~~/~,~/yc,r,fclir.s-This study was supported by U.S. Department of Energy Contract No. EX-76-C-01-2494. The coals used. and their basic characterization data. were obtained from the Penn State/D.O.E. Coal Sample and Data Base. assembled under the direction of Dr. WILLIAM

GIVEN P. H. and YARZAB R. F. (to be of the organic structure of coals: the presence of mineral matter. In Joor Coal cmndCoal Products (ed. C. demic Press.

SPACKMAN.

INTERNATIONAL

Z.. GIVEN P. H. and YARZAI~ R. F. (1978) A re-examination of the phenolic hydroxyl contents of coals. Fuel 57. 95-99. GIVEN P. H.. PEOVER M. E. and WYSS W. F. (1960) Chemical properties of coal macerals-I. introductory surve) and some properties of exinites. fuel 39. 323. GtVEN P. H.. ROVER M. E. and WYSS W. F. (19651 Chemical properties of coal macerals-II. Inert components and a further examination of exinites. Fuel 44, 425-435.

Hard coal: determination of oxygen. Recommendation R 1994. KINSDN K. and BELCHEW C. B. (1975) Determinatton of oxygen in coal and coke using radio-frequency heating method. Furl 54, 205-209. Nt:Tt-:R J. and WASSERMAN W. (1974) Apphd Lirwur Slurisrirul Modth. Richard D. Irwin. inc. (pubs.). Homewood. IL. YARZAB R. F. and GIVEN P. H. (submitted) Relation of coal characteristics to liquefaction behaviourCluster analysis for characteristics of 104 coals. Submitted for publication in Fuel. (1971)

REFERENCES ABDEL-BASET

ORGANIZATION

FOR

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