PRODUCT AND PROCESS DEVELOPMENT
(Long-Chain Vinyl Esters and Ethers)
Cost Estimate on Technical Grade Vinyl Stearate CLIFFORD S. REDFIELD, WILLIAM
S. PORT,
AND DANIEL
SWERN
Eastern Regional Research laboratory, Philadelphia 18, Pa.
I
ITDUSTRIAL interest in vinyl stearate as a comonomer has been increasing rapidly, largely because i t has been demonstrated in laboratory investigations t h a t this substance has certain outstanding characteristics for t h e preparation of internally plasticized copolymers with vinyl chloride ( d o , BS), vinyl acetate ( l e ,d s , d d ) , and other monomers. One important factor which determines industrial acceptance and use of a new monomer is its cost. This Paper attempts t o answer certain questions regarding the cost of production and sale of vinyl stearate. T h e cost estimate given is based solely on laboratory data for t h e preparation of vinyl stearate, described in the preceding article (page 1702). No
Production of 15.625 pounds of technical grade vinyl stearate per d a y or 5,000,000 pounds per year (Table 111) is calulated a8 follows: Raw material per charge Stearic acid Zinc stearate, U.S.P.
Average yield, based on 1.0839 theoretical yield from stearic acid, is 84.3%: Yield per charge 2850 X 1.0839 3089.12 X 0.843
pilot plant results are available; consequently many engineering factors have not been evaluated. Furthermore. t h e cost information given is for a completely new plant and not a n adjunct t o a n y existing plant. Laboratory work has shown t h a t t h e technical gra'de of vinyl stearate and, for some copolymerizations, the crude grade (as defined on Dages 1703-4) are satisfactorv monomers for use i n copolymerizations. For example, copolymers of vinyl chloride containing at least u p t o 35% crude vinyl stearate did not differ in properties from similar copo~ymersprepared with pure vinyl stearate.
Production of vinyl stearate appears commercially feasible Process. Vinyl stearate is prepared from stearic acid (95y0 stearic acid and 5% palmitic acid, melting point 85-67' C.) by vinylation at 165' C., with propane-diluted acetylene under a pressure of 200 pounds per square inch gage, using zinc stearate as a catalyst. This crude product is purified b y flash distillation under an absolute pressure of 0.5 t o 1.0 mm., giving technical vinyl stearate. Yield of crude vinyl stearate, after vinylation, is 94% based on :he theoretical yield from stearic acid. Yield of technical, after flash distillation, is 84.3 % based on the theoretical yield from stearic acid. Operations. T h e estimate given here is based on t h e production of approximately 5,000,000 pounds of technical grade vinyl Etearate per year. Also given (Table V) a r e t h e basic figures for t h e production of 1,000,000 and 10,000,000 pounds of technical grade vinyl stearate per year obtained b y ratios from the calculations for 5,000,000 pounds per year.
Pounds 2850 416
Pounds 3089.12 2604.13
Make 2100 charges per year operating 24 hours per day, 350 days per year: 2604.13 pounds/charge X 2100 = 5,468,673 pounds/year 15.625 pounds/day
Return
On
Investment'The estimate is based
On
a net return
of 12%, a f t e r taxes, calculated on the fixed capital investment. This estimate is composed of five parts: equipment (Table I), capital expenditures (Table 11), cost sheet (Table 111), operational analysis (Table IV), and summary (Table V). Conclusions and Discussion. Monomers t o be used as internal plasticizers must not only yield copolymers t h a t have desirable properties, but they must also be available in the usually accepted price range of external plasticizers (30 t o 50 cents per pound) in order t o furnish a sufficient motivation for their large scale use. For specialty applications, where permanence of plasticizer is absolutely essential, this restriction does not apply. At a production rate of 5,000,000 pounds per year it should be possible t o build a plant and manufacture and sell vinyl stearate a t a profit, after taxes, a t a selling price of about 48 cents per pound. At a n annual production rate of 10,000,000 pounds, t h e selling price could be about 35 cents per pound. However, these cost estimates include not only building a n entirely new plant, but also t h e step of washing t h e catalyst with acetone followed by acetone recovery. This step was employed in the laboratory study t o obtain accurate yield figures, because t h e catalyst separated from t h e autoclave charge contained significant amounts of vinyl stearate adhering t o it. There appears t o he no reason why the unwashed catalyst cannot be
I
I This article describes large scale laboratory preparation, in high yield, of vinyl stearate, vinyl oleate, vinyl octadecyl ether, and vinyl oleyl ether from acetylene and the appropriate commercial grade of long-chain acid or alcohol. The synthesis o f these monomers of purity sufficiently high to ensure polymerizability seems commercially feasible. The monomers have potential commercial interest because their basic raw materials (acetylene and tallow) are inexpensive and readily available. In the copolymers prepared, the long chain is chemically bound in the polymer molecule, and the resulting intramolecularly modified polymers should retain their original properties indefinitely compared with changes, due to exudation, evaporation, and leaching, encountered in plasticized polymer compositions. Cost estimates based on preliminary laboratory data indicate that a plant producing 5,000,000 pounds of vinyl stearate per year should realize a profit, after taxes, from a selling price of about 43 cents per pound; at an annual production rate of 10,000,000 pounds, the selling price could be as low as 3 1 to 3 4 cents per pound. A return of 1270 on the investment, after taxes, i s assumed.
September 1935
INDUSTRIAL AND ENGINEERING CHEMISTRY
,
1707
PRODUCT AND PROCESS DEVELOPMENT
Table 1.
Equipment
cost
cost 2 acetone storage tanks
Bronze centrifugal pump Portable conveyor Conveyor, reversing, storage room Pump, propane, reciprocating Conveyor, storage room to melting kettle Kettle to melt stearic acid and zinc stearate ' Pump, molten stearic acid and zinc stearate to reactors Reactors (4)a '
Tanks (4) for catalyst separation Centrifuge, solid ball continuous Conveyor, screw
2 tanks for collecting Tank for collecting Pump Still
a
l/&-inch carbon steel, 10-ft. ' diameter, 15 f t . 7 inches long Acetone to process, 60 gal. / min. a t 40-ft. head. Class I-D R R siding inload cars, 40 ft. X 30 inch wide side rails. Class I-D 58 f t . long, 36 inches wide. Class I-D 125 lb./sq. inch gage. Class I-D 40 f t . long, 36 inches wide. Class I-D No. 316, stainless steel, C.S. jacket, agitator, 600 gal. P.D. pump, stainless steel, max. 13,500 lb./hr. a t 40 lb. /sq. inch No. 316 stainless steel agitator and jacketed, 300 lb./sq. inch gage working pressure Stainless steel jacketed, agitator and decant pipe, 1269 gal. Stainless steel, 70 gal. /min. to 2000 gal., vapor-tight, 34 X 38 inches. Class I-D 6 inches, stainless steel, 25 f t . long, vapor-tight, sealed feed and discharge. Class I-D Stainless steel, closed, jacketed, 5-ft. diameter, 5 ft. deep, 735 gal. Stainless steel, closed, 4 f t . 6 inches diameter, 5 f t . 6 inches deep, 654 gal. Stainless steel, positive delivery, 14,700 lb./hr. a t 40 lb. /sq. inch Stainless steel with carbon steel jacket, 5 ft. diameter, 5 Et. deep, 735 gal.
I 4,480
Condenser, shell and tube
780
Receiver Pump, bronze centrifugal
2.570
Pump, positive delivery
4,160
Rotary vacuum dryer
600 3,370
Steam jet Condenser
2,850
Acetylene generation
760 102,970
Feed tank, closed Flash tank
21,060
Merrill system
13,420
Condenser, shell and tube
4,590
Receiver Steam jets
1,040 Condenser 700 Tank, wood 760 1,040
Pump, centrifugal
145.6 sq. f t . cooling surface, carbon steel Carbon steel, 150-gal. capacity 30 gal./min. a t 25-ft. head. Class I-D Stainless steel, 16 gal. /min. a t 50 lb./sq. inch. Class I-D Includes dryer, condenser, receiver, and pump. 4 f t . diameter X 20 it. Single jet, 5-inch abs. pressure To kill steam from singlestage steam jet From calcium carbide, $220 / ton year Stainless steel, carbon steel jacket, 5-ft. diameter X 5 It. No. 316 stainless steel, 100 gal., jacketed, 0.5- to 1.0mm. pressure Hot oil to jacket of flash tank, 410-428' F., electrical immersion heater No. 316 stainless steel tubes, heads, and tube sheets, carbon steel shell, 42 sq. ft. 100 gal., stainless steel, 0.5t o 1.0-mm. pressure 0.5- to 1.0-mm. pressure, 4stage in series, intercondenser and aftercooler Kill steam from steam jets, 13.0 sq. f t . , carbon steel construction 6-ft. diameter X 8 f t . deep, with Fulton-Sylphon control, hot water, 160-165'F. Circulate hot water, 50 gal./ min. a t 50 lb. /sq. inch
1.640 260 410 500 1,947 600 50 57.950 1,050 1,240 7.850 1.020 620 5,260 450 530 470 $265,080
Twenty pounds of charge requires 5 gallons of reactor capacity.
Table II. Land and site preparation Roads and park areas Railroad sidings Fences Buildings
20 acres a t $300 /acre $ 16,500 15,110 Road 800 X 20 f t . Park 300 X 60 f t . Black top, $4 /sq. yd . 3000 f t . a t $9 /lineal f t . 27,000 1500 f t . a t $3.50/ft. 5,250 120 X 80ft. Penthouse 15 X 100,410 60 ft.; $9.28/sq. f t . building; $12.58/sq. f t . penthouse 214 boiler hp. a t $78 /bhp. 16,660 Table I
Boilers Equipment. manufactur. . ing Erection of equipment, 30% of equipment cost mfg. foundations, supports and positioning Instrumentation 7.5% of equipment cost Mostly stainless steel and Piping and ductwork steam traced. 40% of equipment cost Erection, piping and 75% of piping cost ductwork Heating installed 2569 sq. f t . a t $2.50 /sq. f t . Lighting installed Vaporproof fixtures, 61 fixt. a t $95 each, 125 outlets a t $9 each
1708
Capital Expenditures
79,520 19,880 106,030
Power installed Transportation facilities, trucks and industrial trucks Insulation Freight on equipment Office furniture and fixtures Analytical and research laboratory Contingencies Engineering fees Fire protection and safety
116.14 kw. Class I-D. At $175/kw. Immersion heaters, 15 kw.
19,900 1922 sq. ft. a t $1.46/sq. ft. plus pipe insulation 2% of equipment cost 1% of equipment cost
4,310 5,300 2,650 40,000
10% of fixed capital 15T0 of fixed capital
112,300 168,480 4,890
Total fixed capital
79,520 6,420 6,920
21,070
1,123,200
Working capital. Inventories, raw materials, in process, finished goods, credits, wages, etc.
463,560
Total capital
$1,586,760
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
Vol. 47, No. 9
.
PRODUCT AND PROCESS DEVELOPMENT Table 111.
Cost Sheet
Production, 15.625 Ib. of technical vinyl stearate per 24-hour day; continuous operation 350 days per year cost Per Prime Cost Material Stearic acid, 17,100 Ib. a t $0.14/lb. Zinc stearate, 137.1 lb. at $0.38/Ib.a Acetone, 2100 lb. at $0.085/lb. Acetylene, 1507 lb. a t $0.14 /Ib. Propane, 285.3 gal. a t $0.04/gal. Nitrogen, 8593 cu. f t . a t $0.60/100 cu. f t .
$2,394.00 52.08 178,50 210.98 11.53 51.64 $2,898.73
Total material cost
$2,898.73 $0,1855 12 helpers*at $
Total prime cost Indirect materials Shipping bags, 156 at $0.21 ea.
612.00 $0.0392
$3,510.73 30.2247 32.76
Total indirect materials Factory overhead Indirect labor Supervision Watchmen, yardmen Mechanics, etc. Office help Truck operator Chemist, works Total indirect labor
$
32.76 $0.00209
$
57.00 33.15 28.00 36,67 46.00 16.00
$
Per pound
Konwage payments Social security Workmen’s compensation Unemployment insurance Vacation time Total nonwage payments
$
$
Utiiities Power. Process, $0.0110 /kw. Steam. Process, $0.65/1000 lb. Water. Process, $0.05/1000 gal. Total utilities Miscellaneous ,Maintenance, repairs, and renewals Process Gasoline Factory supplies Miscellaneous factory expenses
9% $
4.90 9.46 46.33 36.60 97.29 $0.00622 36.38 53.53 25.75 115.66 $0.0074
-
$
192.54 9.10 28.88 25.00
Total miscellaneous
8
255.52 $0.01635
Total indirect expense
$1,046.10 $0.0669
-___
~~ ~~
216 82 $0.01387
Consumption of catalyst (tech. grade) 1 lb./114 lb. product.
Table IV.
Per
Indirect expenses Fixed Insurance, public liability and fire, 170 32.09 64.18 Taxes, 2% 160.45 Interest on fixed capital, 5% 320.91 Depreciation, 10% Total fixed indirect expense 8 577.63 $0.03697
Total
Labor 6 operators a t $1.75/hr.; $1.26/hr. /shift
a
cost Per pound
Operational Analysis (Unit, pound)
$1,262.92 $0.08082 _ ______ ____ 54,806.41 $0.3076 ~
Total factory overhead Factorv cost Interest on working capital, 5 % Research and development expense, 27, Administration and general expense
66.23 133.64 133.56
Cost to make
$5,139.74 $0.3289
Selling cost, 10%
$
Cost to make and sell Profit
$5,807.44 $0.3716 $ 869.58 $0.0557
667.70 $0.0427
~~
Gross sales Returns, allowances, discounts
$6,677.02 $0.4273
Net annual sales Production cost
2,290,219.33 1,682,243.50
Gross annual profit Administration, research, selling expense
607,975.83 327,181.02
Profit before taxes Taxes, income and excess profit, 52%
280.79r81 146,013 30
I
Net annual earnings Earned on fixed capital, 12yo Earned on total capital, 8.49Y0 Dollar sales per dollar invested capital Net profit, earned on gross sales, 5.77% Net profit on net sales, 5,89Y0 Selling price per pound Profit per pound Turnover of total capital used Turnover of working capital, 79.8 days Turnover of fixed property investment Turnover of fixed property investment, physical, 4.87 lb. /dollar Break-even point, 3,243,068 Ib. /yr. 70of capacity, 59.3 Shutdown point, 1,764,688 lb. /yr. % of capacity, 32.3 Pay-out time, years, F&B with 3% debenture bonds, 5.01
September 1955
7
134,781 51 $2 08 $0 4273 980 0246 $1 44 $2 04
Table V. Yearlv - oroduction. lb. 24 hr. daily production, lb. Fixed capital Working capital Total capital Factory cost Per day Per pound Cost to make Per day Per pound Cost to make and sell Per day Per pound Selling price Per day Per pound Annual gross sales Net annual earnings after taxes
Summary
1,000,0005
5,468,673
10,000,000~
2857 15,625 28,571 $405,470 00 $1,123,200.00 $1,612,920.00 $167,340 00 $ 463,560.00 $ 665,670.00 $572,810 00 $1,586,760.00 $2,278,590.00 $ $
$
9%
8 $
1,735 11 $ 0 6073 $
4,806.41 $ 0,3076 $
6,902.00 0.2416
1,855 45 $ 0 6494 $
5,139.74 $ 0,3289 83
7,380.67 0.2583
2,096 49 9% 0 7338 8
5,807.44 $ 0,3716 8
8,339.48 0.2919
9.588.20 6,677.02 $ 2,410 40 9% 0.3356 0.4273 1 0 8437 98 $843,640 00 $2,336,960.00 $3,355,870.00 $ $
$
48,660 00
$
134,780.00
Calculated from 5,000,000 Ib. production: 0.361, and for 10,000,000Ib., 1.436. a
INDUSTRIAL AND ENGINEERING CHEMISTRY
$
193,540.00
ratio for 1,000,000 lb.,
1709
PRODUCT AND PROCESS DEVELOPMENT re-used, as its only “contaminant” is vinyl stearate, the product being made in the first place. Elimination of the acetone wash step significantly lowers the costs of equipment and processing, and also cuts down on t h e over-all operating time. At a n annual production of 5,000,000 pounds, elimination of t h e acetone wash reduces the selling cost of vinyl stearate t o about 42 cents per pound and at 10,000,000 pounds t o about 31 cents. Acknowledgment
T h e authors would like to thank Sidney Siggia and his staff
at t h e Central Research Laboratory, General Aniline and Film Corp., Easton, Pa,, for all analytical determinations. literature cited
Adelman, R. L., J . Org. Chem., 14, 1057 (1949). Beller, H., Christ, R. E., and Wuerth, F., U. S. Patents 2,472,084, 2,472,086 (June 7, 1949) ; Brit. Patent 641,438 (Aug. 9, 1950). Bertram, S. H., Rec. trau. chim., 46, 397 (1927). Brice, B. A.. and Swain, hf. L., J . Opt. Soc. Amer., 35, 532 (1945). Brice, B. A., Swain, hl. L., Schaeffer, B. B., and Ault, W. C . , Oil and Soap, 22, 219 (1945). Brown, J. B., and Shinowara, G. Y . , J . Am. Chem. SOC., 59, 6 (1937). Cirpenter, G. B., FIAT Final Report 935, PB 52163 (1946). Ibid., 936, PB 58441 (1946). Copenhaver, J. W., and Bigelow, M. H., “Acetylene and Carbon Monoxide Chemistry,” Reinhold, New York, 1949. Mkentscher, H., Kuko Report 106 (ilpril 1937), PB A 76327, listed in BSIR 5. No. 10. 850 (June 1947). Fikentscher, H., U. S. Patent 2;016,490 (Out. 8, 1935); Ger. Patent 634,408 (Aug. 26, 1936). Harrison, S. A., and Wheeler, D. H., J . ’Am. Chem. Soc., 73, 839 (1951). Herrmann, W. O., and Haehnel, W., U. S. Patent 2,245,131 (June 10, 1941). Kollek, L., Ibid., 2,045,393 (June 23, 1936). NBsslein, J., and Finck, G. von, Ibid., 2,168,535 (Aug. 8 , 1939), 2,234,501 (March 11, 1941). Nusslein, J., Finck, G. von, and Stlirk, H., Ibid., 2,168,534 (Aug. 8, 1939). Paloheimo, O., Suomen Kemistilehti, 23, 71 (1950). Port, W. S.,Hansen, J. E., Jordan, E. F., Dietz, T. J., and Swern, D., J . Polymer Sci., 7, 207 (1951). Port, W. S., Jordan, E. F., Hansen, J. E., and Swern, D., Ibid., 9, 493 (1952). Port, W. S.. Jordan, E. F., Jr., Palm, W. E., W-itnauer, L. P., Hansen, J. E., and Swern, D., IND.ENG.CHEM.,47, 472 (1955).
(21) Port, W. S., Jordan, E. F., Jr., Palm, W. E., Witnauer, L. P., ‘ Hansen, J. E., and Swern, D., U. S. Dept. Agr., Bur. Agr. Ind. Chem., AIC-366 (1953). (22) Port, W. S., Jordan, E. F., and Swern, D., U. 9. Patent 2,586,860 (Feb. 26, 1952). (23) Port, W. S., Kincl, F. A., and Swern, D., Ofic.Dig., Federation P a i n t & Varnish Clubs, 26, 408 (1954). (24) Port, W. S., O’Brien, J. W., Hansen, J. E., and Swern, D., IND. ENG.CHEM.,43, 2105 (1951). (25) Powers, P. O., Ibid., 38, 837 (1946). (26) Reppe, W., U. S. Phtent 1,959,927 (May 22, 1934) ; Ger. Patent 584,840 (Sept. 7, 1933). (27) Reppe, W., U. S. Patent 2,066,075 (Dec. 29, 1936); Ger. Patent 588,352 (Nov. 2, 1933). (28) Reppe, W., and Schlichting, O., U. S. Patent 2,104,000 (Dee. 28, ,1937). (29) Reppe, W., Starck, W., and Voas, A., Ibid., 2,118,864 (May 31, 1938); Ger. Patent 593,399 (Feb. 8, 1934). (30) Rosen, R., and Sparks, W. J., U. S. Patent 2,468,516 (April 26, 1949). (31) Siggia, S., and Edsberg, R. L., Anal. Chern., 20, 762 (1948). (32) Skellon, J. H., J . Soc. Chem. Ind., 50T, 131 (1931). (33) Swern, Daniel, Eastern Utilization Research Branch, Philadelohia. Pa.. orivate communication. (34) Swern, D., Billen, G. N., and Knight, H. B., J . Am. Chem. SOC., 69, 2439 (1947). (35) Swern, D., and Jordan, E. F., Ibid., 70, 2334 (1948). (36) Swern, D., and Jordan, E. F., Org. Syntheses, 30, 106 (1950). (37) . . Swern. D., Knight, H. B., and Findley, T. W., Oil and S o a p , 21, 133.(1944). (38) Swern, D., Scanlan, J. T., and Roe, E. T., Ibid., 23, 128 (1946). (39) Toussaint, W. J., and MacDowell, L. G., U. S. Patent 2,299,862 (October 27, 1942). (40) Twitchell, E., J. IND.ENQ.CHEM.,13, 806 (1921). (41) Voss. A., and Dickhauser, E:, U. S. Patent 2,047,398 (July 14, 1936). (42) Voss, A., and Stark, H., Ibid., 2,160,375 (May 30, 1939). (43) Weber, K. H., and Powers, P. O., Ibid., 2,518,509 (dug. 15, 1950). (44) Wulff, C., and Breuers, W., Ibid., 2,020,714 (Nov. 12, 1935); Ger. Patent 600,722 (Feb. 15, 1936). (45) Ziegler, K., ed., “Preparat,iveOrganic Chemistry,” by Hecht, O., and Kroeper, H., in Field Information Agencies Technical, U. S. Dept. Commerce, PB 99207, pp. 6-24 (1948). ACCEPTED March 25, 1955. RECEIVEDfor review August 11, 1954. Presented before t h e Division of Industrial and Engineering Chemistry a t CHEMICAL SOCIETY, Kansas City, Mo., the 125th Meeting of the AMERICAN 1954. Report of work done in part under contract with the U. S. Department of Agriculture and authorized by the Research and Marketing Act of 1946. Contract supervised by Eastern Utilization Research Branch, Agricultural Research Service. Reference to commercial products in this paper is not intended t o be a recommendation of these products by the U. s. Department of Agriculture over others not mentioned. The Eastern Regional Research Laboratory is 8 laboratory of the Eastern Utilization Research Branch. Agricultural Research Service, U. S. Department of Agriculture.
Pentaerythritol Production Yields M.
S. PETERS
AND
J. A. QUI“‘
Universify of Illinois, Urbana, Ill.
P”
NTAERYTHRITOL is a n important chemical produced by reacting acetaldehyde with formaldehyde in a n alkaline medium under rigorously controlled conditions. One of t h e major factors in the economic production of this material is the attainment of high over-all yields and good grade product. Yield losses can occur in the chemical reactions involved in the process and in t h e physical operations necessary for separating t h e pentaerythritol from the reaction mixture. T h e published information relating t o t h e synthesis of pentaerythritol is found almost entirely in United States patents. Among these patents, there are considerable differences in t h e procedure followed and in the yields claimed. However, t h e main differences center on two topics 1 Present address, Princeton University, Princeton, N. J.
1710
1. The type and amount of alkaline catalyst used 2. T h e time and temperature of the reaction Other variables of importance in t h e process a r e the ratio of formaldehyde t o acetaldehyde in t h e reaction mixture, water content of t h e reaction mixture, choice of acid t o neutralize the excess alkali, method of separating the pentaerythritol from the reaction mixture, and purity of the reactants. I n this work, all these variables have been taken into consideration, and results are presented showing the effect of time, temperature, and type of catalyst on production yields. T h e first stage in t h e stepwise reactions producing pentaerythritol is a n aldol condensation of acetaldehyde with formaldehyde in t h e presence of alkali t o form pentaerythrose as shown by
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
Vol. 47, No. 9
