Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

The production of liquid hydrocarbons by the Fischer-Tropsch synthesis Buck, F.A. Mackinnon 1944

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata


831-UBC_1944 A7 B8 P7.pdf [ 1.66MB ]
JSON: 831-1.0059083.json
JSON-LD: 831-1.0059083-ld.json
RDF/XML (Pretty): 831-1.0059083-rdf.xml
RDF/JSON: 831-1.0059083-rdf.json
Turtle: 831-1.0059083-turtle.txt
N-Triples: 831-1.0059083-rdf-ntriples.txt
Original Record: 831-1.0059083-source.json
Full Text

Full Text

THE PRODUCTION OF LIQUID HYDROCARBONS BY THE FISCHER-TROPSCH SYNTHESIS  by F. A. Mackinnon Buck, B. A. Sc.  A Thesis submitted i n p a r t i a l fulfilment of the requirements for the Degree of MASTER OF APPLIED SCIENCE i n the Department of CHEMICAL ENGINEERING  The University of B r i t i s h Columbia A p r i l , 1944.  TABLE OF CONTENTS Page I  Introduction (A) (B)  II  (C) (D) (E)  Operation The catalyst  Appendix (A) (B) (C) (D)  15.  General Description Reaction Chamber Solenoid Temperature Control Condensers  Experimental Work (A) (B)  Y  Principal Reactions Equilibrium Calculations (1) Discussion (2) Calculations for Methane (3) Extension to higher homologues The Catalyst Influence of Magnetic F i e l d Other Factors (1) Composition of reactant gas (2) Size of reaction tube (3) Influence of catalyst concentration (4) Influence of flow velocity  Apparatus (A) (B) (0) (D) (E)  IV  3-  Theory (A) (B)  III  Object of Research Historical  References Heats of formation Free energies of formation Out-throw diagram  19.  THE PRODUCTION OF LIQUID HYDROCARBONS BY THE FISCHER-TROPSH SYNTHESIS I  Introduction (A)  Object of Research This research was undertaken i n an attempt  to investigate a few of the factors influencing the hydrogenation of carbon monoxide to l i q u i d hydrocarbons by the so called Fischer-Tropsch Synthesis.  The  investigations o r i g i n a l l y planned were: (1)  The influence of different catalysts  (2)  The influence upon the rate of reaction  and the products obtained of a superimposed magnetic f i e l d . It i s evident, however, that before any conclusions regarding the effect of these two factors may be made, some sort of reaction standard must be adopted to act as a blank against which results may be compared.  In  other words i t was necessary f i r s t of a l l to design and build an apparatus so that a l l process variables except the two under consideration could be maintained constant; and secondly to make enough runs under normal operating conditions to establish some sort of a standard of comparison for reaction rate, products obtained, catalyst l i f e , thermal efficiency, and so f o r t h . (B)  Historical  It has long been known as a result of the 1 pioneering work of Sabatier that f i n e l y divided nickel 1.  w i l l catalyze the hydrogenation of carbon monoxide to methane, ffischer and Tropsch were among the f i r s t to show that with the proper selection of the catalyst the methane reaction of carbon monoxide and hydrogen may be modified so d r a s t i c a l l y that the principal product i s a complex mixture of higher paraffin hydrocarbons o r i g i n a l l y known as "Synthen" but more recently given the appropriate name "Kogasin". Like the Berguis process, the Kogasin process provides a new method for the chemical conversion of coal to l i q u i d products, and i s looked upon as a p a r t i a l solution to the diminishing resources of crude petroleum.  Kogasin consists almost wholly of straight  chain hydrocarbons.  I t i s unsuitable for motor fuel unless  i t i s blended with antiknock agents or re-formed by cracking.  The higher fractions, however, are eminently suited  to use as Diesel fuels and lubricants.  I t i s not surpris-  ing, therefore, that technological progress has been rapid, and that the Fischer-Tropsch synthesis i s already a well established industrial process i n Germany.  3. II  Theory. (A)  Principal Reactions The Kogasin synthesis i s , complicated by the  fact that a single set of reactant gases w i l l give a wide m u l t i p l i c i t y of products, depending upon the control of the operating conditions.  The following reactions w i l l  indicate some of the more important possible syntheses, a l l of which have been more or less established industrially: (1)  CO + H2  HCHO  (2)  CO + 2H '  CH OH 3  (3)  CO + 3H0 2  CH + H O 4 2  (4)  nCO -f- (2n)H2  (5)  nCO + (2n + l ) H 0 =?=^ C H -t- nH 0 2 n 2n-h 2 *  ^  C n H 2 n + 1 QH  -r (n-l)H 2 0  ?  Fortunately the catalysts required and the equilibrium conditions for the formation of oxygenated compounds, such as formaldehyde and methanol, are such that these do not take place to any appreciable extent i n the range of the Kogasin synthesis.  The actual problems  i n this process are how to keep the formation of the Kogasin fraction (b.p. 50 - 200° C ) at a maximum and the formation of the v o l a t i l e gases ( i . e . methane, ethane, Sec. ) and the heavy waxes at a minimum.  4. (B)  Equilibrium Calculations (l)  Discussion  Thermodynamic calculations w i l l be applied to the formation of hydro carbons by the hydrogenation of carbon monoxide.  In particular , free energy equations are  to be investigated for reactions of the following type: (1)  CO + 3H ,  (2)  2C0 H~ 5H  (3)  3C0 •+ 7H 2 ^  2  2  CH4-t-H20(g) C  -t- 2H20(g)  C ? H 8 ~t 3H 2 0(g)  or, i n general, (4)  nCO -+- (2m-l)H 2  ^  C n H ^ - H n^OCg) 2 n  1  Carrying out a reaction of this type involves the following problems:  (1) How fast can the reaction be  made to take place; and (2) What i s the maximum possible yield under given conditions of temperature and pressure? The rate of the reaction depends largely on the catalyst used, and hence must be determined experimentally.  But  before the efficiency of the catalyst can be tested i t i s necessary to find out under what donditions of temperature and pressure the reaction i s thermodynamically possible of taking place, and what the maximum yield, would be given a favourable rate.  I t i s also helpful to know the thermo-  dynamics of other possible reactions, so that may be adjusted to exclude undesirable  conditions  side reactions.  3. (2) Calculation of Equilibrium Constant f o r Methane Reaction . CO -4- 3H  CH  0  H 0(g)  4  2  2  To calculate the equilibrium constant of the above reaction i t i s necessary to calculate the free energy change (  <3 ) as a function of the temperature.  The method employed w i l l be the integration of the specific heat equations for the substances involved.  The equations 2  used were (a) determined CO: ~ C p s from spectroscopy data by Bryant : (b)  H2:  Cp  (c)  C H C 4  (d)  P Cp  H20:  3  6.88 -+• .000066T -h .000000279T2  =  6.25 -h .002091T  =  3.38 -+- .017905T 6.89 -+- .003283T  - .000000459T2 2 - .O00004188T 2 - .000000343T  Combination of these equations i n the usual manner leads to the following expression:  =  - 16.62 -+• .018 899 T •+ .000 004 909T2  To obtain an equation for the heat of reaction, r e c a l l  and by integration  * H - ^ r where <4M0is  -r 3  T i - ^ ^  a  to  the constant of integration.  To get the free energy equation, substitute f o r ^ H  = — J^=i. ^ ^~  «/ (J  i n the expression which gives  =  _ // A  ~ ^7 7 - - ^JS  4 ^ = £g? -^/z^~r  ^1  -^1/7 TVw 7"-  =  . 4 / ; 7-^7- ,  ^  ,  T -  2  7  ^  o  T " * 7 (2)  where I i s another constant of integration. The f i n a l equation now contains two constants. These are evaluated i n the following manner: (1)  To evaluate  ^  /L\  i s calculated f o r the reaction  from the heats of formation of the products and reactants at 18°C and 1 atm. pressure. ^  z i > l  =  (see appendix 1 )  - 50,500  c a l . per mol.  This value i s substituted i n equation (l) for heat of reaction, giving  =  (2)  - 46,500  cal per mol.  To evaluate integration constant I The free energy change for the reaction i s  calculated f o r 25°G by the summation of the standard free  7. energies of formation (see appendix 2 }: &&  ~ ~ 33,blO c a l . per mol.  Z S 8  This value and the value of  are substituted i n  equation (2), giving " - 33, €>/o -  T(29Q)  I  =  -+- A Sg (^S>S)(23) /oS(zs>e)  - 14,460 - 48.5  The f i n a l free energy equation then becomes:  To get the equilibrium constant from the free energy change, use the, relation Z±6  -  or, In K  -  - RT In K (4) (2.303) RT  Example: To get the equilibrium constant f o r the reaction at 200°C (473° A): Erom equation (3) =  - 23,200 cal per mol.  Substituting this value i n equation (4) K = 5.4 x 1 0  1 0  8. The variation of the equilibrium constant with temperature i s shown by the following table, using results calculated from equations (3) and ( 4 ) .  Temp, deg. c 25  (3)  K 1.4 x 10 2 ^  100  1.02 X 1 0  200  5.4 X 1 0 1 0  300  2.8 x 10 5  1 7  Extension to higher homologues.  Oalculations of the equilibrium constants of several different hydrocarbons have been made by 3 Smith  i n a paper published i n 1927.  Although the c a l -  culations for methane made i n this thesis were from more recent data, the results obtained were i n close enough agreement to Smith's results to j u s t i f y accepting his values for the higher homologues. Eigure 1 shows graphically the variation with temperature of the calculated values of the e q u i l ibrium constant for the reaction. nCO + (2n-*-l)H — ^ C n 2 n 2 H  ^2°  Analysis of Figure 1 shows that i t becomes increasingly easier to form the higher paraffin hydrocarbons than the lower members at a l l temperatures.  I t should be  Figure 1 Variation of Equilibrium Constants with Temperature  > 10. possible, given suitable catalysts, to form any of the paraffin hydrocarbons at atmospheric pressure.  The tendency  to form these compounds f a l l s off rather rapidly with increased temperature. (C)  The Catalyst The catalysts most suited for the kogasin  synthesis are the metals iron, cobalt, and nickel - these metals have the common property of forming carbides. 4 outlined by Fischer  As  the reaction i s catalysed by the  formation of metal carbides of the formula Me C at the active centres of the catalyst.  In the presence of hydrogen  the carbide i s converted again into metal while (CELj) radi c a l s are formed. The reaction i n the case of cobalt and nickel below 200°C i s as follows: 2H0 -+- CO -t~Ni C Ni,C 0 -f- H0 c  p  y  hi C -h H. 3 2  2  <-  HO  c  d  >• Ni C -h (CH } 3  2  Additions to the true catalytic metals are materials that have characteristic chemical action.  The  addition of copper to cobalt and iron catalysts activates the catalyst since i t lowers the reduction temperature for oxides; however i t acts adversely i n the presence of n i c k e l . Other additions, such as manganese and aluminum, which are simultaneously precipitated with the* catalytic metal, appear to play a part i n obtaining certain configurations or l a t t i c e structures of the metallic alloy i t s e l f .  The use of  . 11. kieselgur greatly aids In the d i s t r i b u t i o n of the actual catalyst by an increase i n the surface area of the contact material. In another a r t i c l e , Fischer claims the best catalyst to be a mixture of Ni - Mn - A l prepared by precipitating the oxides on kieselgur.  This was the catalyst  chosen for the present investigation. Details for preparation w i l l be given l a t e r . (D)  The Influence of the Magnetic F i e l d According to Bhatnagar  there are theoretical  reasons why an impressed magnetic f i e l d should influence chemical reactions.  In chemical reactions, even i f no  change of valence i s involved, there may  be a change i n the  magnetic moments of the i n i t i a l and f i n a l products.  If  during the reaction the magnetic moments tend to decrease, then the presence of an external f i e l d w i l l t r y to "conserve" the magnetism, and so retard the reaction.  On the other  hand, i f the magnetic moment increases during the course of reaction, then the presence of a f i e l d w i l l further help the increase and so accelerate the rate of reaction.  Also, i n  a magnetic f i e l d the atoms tend to assume certain definite positions relative to cue another.  Thus the collisions with-  i n the f i e l d should take place i n a more orderly and directed manner, and the rate of reaction should change. It seems l o g i c a l , therefore, that a chemical transformation from diamagnetic to paramagnetic (or less  12. diamagnetic) state should be accelerated, and that from a paramagnetic to diamagnetic or from feebly diamagnetic to more strongly diamagnetic state should be  retarded.  This result can be expressed symbolically by the following: (1)  (2)  where  X/w  2! X  > ]E! X ^ M * <C  M p  then reaction i s accelerated by f i e l d .  X  M  then reaction i s retarded the f i e l d .  «  by  ^ X/v,p s the sum of the molecular s u s c e p t i b i l i t i e s of the f i n a l products. ZT X/v] = the sum of the molecular s u s c e p t i b i l i t i e s of the i n i t i a l reactants. R  Equations (1) and (2) above would indicate the p o s s i b i l i t y of making predictions as to the effect of a magnetic f i e l d on the water gas reaction.  A complete  analysis i s not possible, however, because the molecular s u s c e p t i b i l i t i e s of some of the compounds involved ( i n particular CO) have not been recorded i n the l i t e r a t u r e . In a summary of Pascal's work on molecular 7 s u s c e p t i b i l i t i e s , Farquharson may  recalls that  be treated as an additive property.  is: where N a  susceptibility  Pascal's expression  ^ 1* . - Z * J a X * m i s the number of atoms i n the molecule of  s u s c e p t i b i l i t y . X , and a  A  i s the constitutive constant  13. depending on the chemical linkage. 8 In another a r t i c l e  Farquharson calculates the  molecular susceptibility of the -CHg-  gorup i n combination  to be X  m  •  - 11.64 z 10"  6  per  -CHC2  In view of previous reasoning, then, i t i s to be expected that a magnetic f i e l d w i l l favour the formation of smaller homologues. Pascal has also shown experimentally that any organic reaction involving the change from a -G=C-  double  bond to two single bonds w i l l cause a r i s e i n diamagnetic  -6 susceptibility of 3'5 x 10~ .  This leads to the prediction  that a magnetic f i e l d would cause a greater proportion of unsaturated compounds. The above values for molecular were a l l given for room temperature.  susceptibilities  At elevated temperatures  the s u s c e p t i b i l i t i e s w i l l decrease, according to Curie's law (X) T m  constant  In view of the facts that molecular velocities are greater at higher temperatures, that the s u s c e p t i b i l i t i e s decrease, and that the effects of the magnetic moments are small even for f a i r l y large f i e l d s , i t might be that the change i n the reaction Is so small as to be p r a c t i c a l l y unnoticeable.  14.  (E)  Other Factors (1)  Composition of Reactant Gases 9  It has been reported by Watanabe  that the  best reactant mixture i s that which contains COrH^ i n the ratio 1:2.  A higher percentage of CO results i n decreased  y i e l d and increasing o l e f i n content, and a higher percentage results i n increasing saturation and more gaseous products. The d i l u t i o n of the raw gas with inert gases (Ng, COg, and etc.} causes the increased production of gaseous olefines and CO2, as i n the case of the mere lack of when the velocity of the hydrogenation i s decreased owing to the reduced p a r t i a l pressure of H^.  Moreover, the lower-  ing of the p a r t i a l pressure of CO by the introduction of inerts brings forth unfavourable conditions for polymerization, and consequently the ratio of o i l formation i s gradually decreased as the inert concentration of the raw gas becomes larger. (2)  Size of Reaction Tube  A series of papers by the Institute of  10  Physical Chemistry (Tokyo)  sums up the influence of the  bore and length of the reaction tube as follows: With lOg. nickel catalyst a bore of 13mm. i s most favourable. 30cms.  A 2Oram reaction tube must be longer than  With constant bore the decrease of reaction tube  length promotes the formation of gaseous hydrocarbons.  With  decrease i n tube length^ the most favourable reaction temp-  erature decreases and the v o l a t i l i t y of the product increases. (3)  Influence of Catalyst Concentration  I f more than a certain amount of catalyst i s used (constant velocity being assumed) the reaction reaches a condition of equilibrium independent of the amount of catalyst used.  The l i m i t i n g amount depends on the quality  of the catalyst and the conditions of the experiment. Polymerization, hydrogenation, heavy hydrocarbon formation and CQg formation are promoted by the use of too large a quantity of catalyst.  When the most  favourable amount of catalyst i s used the formation of gaseous hydrocarbons i s at a minimum. (4)  Influence of Current Velocity  The optimum gas velocity i s apparently  /•/ 2/hr  for 1 g. catalyst ( at a temperature of 197 C.)  Wide variations i n velocity do not markedly effect the most favourable reaction temperature, but marked changes occur i n the composition of the kogasin, the formation of COg, heavy hydrocarbons, and e t c . Ill  Apparatus (A)  General Description The essential parts of the apparatus are  shown on the out-throw diagram included i n the appendix. A photograph of the assembled equipment i s included also. The reactant gas mixture i s forced from resevoir (c) by water from the constant head device ( a ) .  17.  Entrapped a i r bubbles are bled off at trap (b). The rate of flow of the gas i s regulated by a valve (d) and i s indicated by the micro flowmeter (e).  The gas then flows through three  drying towers (f) containing CaCl  , KOH, and f i n a l l y P 9 0 c .  The gas enters the glass reaction chamber (g) through a tube (h) which also contains a thermocouple w e l l . The temperature i s controlled by a surrounding resistance c o i l (j) regulated by an autotransformer. thermocouple w e l l . the  (i) i s another  Two manometers (k, k) assist i n regulating  pressure throughtout the chamber. A trap (l) catches the least v o l a t i l e products,  while the gases enter a condenser (m) at the end of which there i s another trap.  The uncondensed gas passes next through  two more condensers cooled by "dry-ice" (n) and l i q u i d a i r (o) respectively.  The remaining uncondensed gases see, collected  over water i n resevoir (p). An adjustable siphon arrangement (q) removes the water from the resevoir and helps regulate the pressure throughout the system. (B)  Reaction Chamber The size of the reaction chamber was chosen  for a through-put of 4 l/hr.  I t i s made from pyrex glass  tubing, l 8 m m . inside diameter and 7 5 c m s . long.  The tube i s  at an angle of 1 5 ° , which i s well below the maximum angle of repose of the catalyst.  The catalyst i s distributed evenly  along the bottom of the tube, to a depth of approximately 8mm.  Small glass thermocouple wells are sealed i n at both  18. ends of the tube.  These thermocouple wells l i e right on the  surface of the catalyst and give an accurate measurement of the  temperature of the surface of the catalyst. (C)  Solenoid The magnetic f i e l d and the heat necessary for  the  control of the reaction are both supplied by a solenoid  of No. 14 B. & S. bare copper wire wound on a brass tube 3-5  •^^r cms inside diameter. The wire i s spaced one diameter apart and each layer i s separated from the next by asbestos insulation. For measuring the strength of the magnetic f i e l d a small search c o i l was designed f o r use with W. G. Pye and Co. fluxmeter, No. 6860. The search c o i l has 200 turns of ffljG magnet wire with an average cross sectional area of 4.12 sq. cms. and a total resistance of 24.8 ohms. The fluxmeter was recalibrated and the correction factor was found to be l.jjb. (D) Temperature Control It was desired to keep the temperature of the  reaction chamber within plus or minus two degrees.  Two thin glass thermocouple wells were sealed i n the reaction tube so that they rested on the surface of the catalyst. The thermocouples were made from copper-copel ^30 B.&-S. wire. The e.m.f. produced i s measured on a Leeds and Northrup Student* potentiometer, using a  L. Sc/V. table galvanometer with a  sensitivity of 0.18 microvolts per mm.  With this arrangement  19. the  temperature could be quite accurately read to one tenth  of one degree. (E)  Condensers. The products of the reaction are separated  and analyzed by liquefaction of the different fractions at different temperatures. The f i r s t trap (1) catches the heavy o i l s and some water vapour.  The remaining water vapour  and the kogasin fraction i s condensed i n the water cooled condenser (m).  Condensers (n) and (o) are made from spirals  of glass tubing and have a small trap at the bottom.  The  f i r s t condenser i s packed with carbon dioxide snow and retains a l l hydrocarbons from propane and propylene up.  The second  condenser i s immersed i n l i q u i d air (b.p. - 196°) and 'theoretically should condense a l l remaining hydrocarbons down to ethane (b. p. - 1 6 2 ° ) , but apparently a l l the ethane i s not retained and some passes on to the receiver. IV  Experimental Work (A) Operation At the time of writing nine separate runs had  been made, without the superimposed magnetic field.  For these  blank runs a heater c o i l was made by winding 20 feet of fid nichrome wire on a l|- t t glass tube and insulating i t with asbestos paper. the  Carbon dioxide and hydrogen were mixed i n  resevoir (capacity 20 litres},'the reaction chamber  brought to 200 °C, and the gases passed through at the rate of 4 l/hr.  The pressure i n the reaction tube was kept below  20. 2 inches of water (the drop i n pressure due to f r i c t i o n i n the  tube was less than one tenth of an inch).  I f at the end  of the five hour run there had been l i t t l e reaction, the original mixture was returned through the apparatus. However, no satisfactory results were obtained because, apparently, of the  inactivitynof the catalyst. (B)  The Catalyst The catalysts were made up according to  3  directions given by Fischer  as follows:  To a solution of 250 parts Ni(NO,)2.6H0O3 Mn(NO^)p.bHgO, 34 parts AUNO3)3.9H2O i n 600 parts d i s t i l l e d water there are addea i n the cold b0 parts kieselgur. There i s next added a solution of 210 parts anhydrous K2CO3 i n 600 parts d i s t i l l e d water and the precipitate which.forms (plus the whole solution) i s brought to a b o i l and f i l t e r e d from the solution. The precipitate i s washed with 600 parts of hot water, and i s dried i n an a i r stream at 110°C. The dried moss i s ground to a powder i n a mortar for reprducible r e s u l t s .  50 parts  Fischer makes no mention of reducing the catalyst.  At f i r s t i t was attempted to reduce the catalyst  i n the reaction chamber with the H 2 - CO mixture but with l i t t l e r e s u l t , reduction was too slow and hydrocarbon formation was  nil. Three additional catalysts have so far been  prepared,, reduction temperatures being chosen as 250, and 450  degrees C.  300,  Other modifications were attempted also,  such as washing more thoroughly, and using pre-boihd kieselgur None of these catalysts gave very .good r e s u l t s . A study of the reasons for the i n a c t i v i t y of catalysts indicates that t h e i r a c t i v i t y may be reduced by:  21. (1)  sulfur poisoning  (2)  l o c a l overheating at the surface  (3)  reduction at too high a temperature  The p o s s i b l i l i t y of sulfur poisoning being the cause of the i n a c t i v i t y was eliminated i n two ways: f i r s t , absolutely pure CO was prepared from formic acid, and second, a sample of inactive catalyst was tested quantitatively for s u l f u r .  There was none.detected. Local overheating i s not possible because of  the fact that the thermocouples are right at the surface of the catalyst. This seems to indicate then that the trouble l i e s i n the method of reducing the catalyst.  Work i s s t i l l  being carried on and this possibility i s being investigated.  REFERENCES  1. Sabatier-Reid, "Catalysis i n Organic Chemistry", D. Van Nostrand Co., New York, 1923, p. 144. 2.  Bryant, W. M. D., Ind. Eng. Chem., 23, p. 820 (1933)  3.  Smith, D. F., Ind. Eng. Chem., 19, p. 801 (1927)  4.  Fischer, Franz, Petroleum Refiner, 23, No. 2, February, 1944.  3.  Fischer, Franz, Roelen, and F e i s t , Petroleum Refiner, 22, No. 12, December, 1943.  6.  Bhatnagar, S. S., P h i l . Mag., Series 7, V o l . 8, p. 457 (1929)  7.  Farquharson, J . , Trans. Faraday Soc., 32, p. 219(1936)  8.  Farquharson and S a s t r i , Trans. Faraday S o c , 33, p. 1472 U937).  9." Watanabe, S., J . Soc. Chem. Ind. Japan, Suppl. Binding, 38, p. 328-31 (1933). 10.  S c i . Papers Inst. Phys. Chem. Research (Tokyo), Chem. Abstracts 30, 8570 - 8.  APPENDIX  (B)  Heat of Reaction from standard heats of formation C0^3H2  &MZ9I = A\  — ^ CH4-f-H20(g)  (products)  — ^> ^ ^  (27th. ed.)  From data i n Chemical Rubber Co. handbook AH.  u  -  =  (reactants)  - 26,428  AH.  19,100  CO  0  AK  - 76,926 1- 26,428 - 50,498  A/S2S>, - - 50,500 cal per mol. (C)  Free energy change from free energies of formation.  *- CH4 -h H20(g)  CO + 3H 2  /^G  -  A G°  (products)  From Chem. Rubber Co. handbook,  AG%^  - 11,617  —  IE. ^ &°  (27th. ed.) Co  -  - 32,510  =  - 66,124  i- 32,510 - 33,614  •AG2gg  5  (reactants)  - 33,610 caliper, mol.  0  APPARATUS  see  p. 17  


Citation Scheme:


Citations by CSL (citeproc-js)

Usage Statistics



Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            async >
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:


Related Items