Document M4Bp8aODBME32D50VeB5Xxyx7

STATUS REPOR X--------- --------------------------- ------ SUSPENSION VINYL RESINS^ RESIDUAITVINYL CHLSRIDE^BrQSAN HOMOPOLYMER AS FUNCTION OF STRIPPING CONDITIONS Author: A. A. Peterson Supervisors: Dr. J. C. Chaty Mr. R. L. Frantz Date: June 28, 1974 Project No. 216B10 File: 19631 SUMMARY Because of potential pressure by OSHA and EPA to reduce residual vinyl chloride monomer in resin distributed to processors, a study was under taken to determine the effects of vacuum stripping conditions on the residual VC1 in the general purpose homopolymer QSAN. In brief, the most significant variable was shown to be stripping temperature. At 90 4 C stripping temperature, all samples, regardless of time, studied amount of vacuum (as long as one exists), or particle size, the residual VC1 was 70 ppm or less. Moreover, three of the four samples stripped at 90*C contained 10 ppm or Less VC1 for an average of 20 ppm. Current production resin (QSAN) being stripped at 704C and 15 inches of vacuum contains an average of 275 ppm VC1. An increase from 70 to 80*C in stripping temperature should lower the residual VCl to 100 ppm or Less. This increase was made on the North and East lines on June 14, 1974%based on these results and recommepdations. A multiple regression analysis was also run on the data. It confirmed the eyeball analysis of the graphed data but also provided the following results: (1) for each 10*C increase in stripping temperature the reBiduaL monomer de creased by 550 ppm, (2) for each .25 hour of exposure time the monomer decreased by 160 ppm, and (3) for each 5 inches of vacuum the monomer content decreased 260 ppm. The temperature accounted for 65% of the variability. ucc 041530 S TATUS REPORT 2. DISCUSSION Figure VI shows the apparatus used in this experiment. Normal production homopolymer (165 micron QSAN) and a pilot plant sample of 100 micron size QSAN were evaluated in this series of tests. The sampLes were taken as slurry samples out of the blowdown tank immediately after venting the high pressure residual monomer to the recovery system. The procedure used for stripping the slurry samples is contained in the Appendix, The first test proved unreliable (Table I) because of the procedure of drying the stripped resin overnight in the oven. Even the unstripped sample analyzed as ''nil" after being in the oven overnight. Thus the procedure was changed to delete the oven drying and simply run residual VC1 on the decanted wet cake (running total solids on each sample to allow calculations on a resin basis). Table II shows the results of the second test which utilized the procedure of the first test sans the oven drying. Figures I, II, and III show the results of residual VCl versus the stripping conditions. Only stripping temperature showed a significant trend in affecting the residual VCl in the resin. Table III shows the result of the third test which varied only time and temperature at 15 inches of vacuum on each sample. The vacuum decreased to 9 inches at 90*0 because of boiling. Figures IV and V show the plots of the residual VCl versus temperature and time. Here again with as littLe as 15 minutes exposure time, temperature was the controlling factor. A multiple regression analysis was run on the data using midpoints of the following: 50 "C stripping temperature, ZZ inches of vacuum, and about 40 minutes of exposure time. The resulting equation relating the residual monomer to the stripping conditions is as follows: + ppm VCl = 1634 - 228 (time) - 1641 (temp) - 361 (VAC), where time is - 20 minutes, or about 10 ppm/minute, temp is plus or minus 30*C or about 55 ppm/*C, and VAc is plus or minus 7 inches or about 51 ppm/inch of vacuum in the range of the experimental conditions (20 - 90*C, 15 minutes - 1 hour, and 15-29 inches of vacuum). ucc 047531 S TATUS REPOR T 3. CONCLUSIONS AND RECQMMENDATIONS From these brief, but consistent, experiments, it is concluded that stripping temperature is the most important variable in the reduction of residual vinyl chloride in QSAN homopolymer. It is recommended that the stripping temperature be gradually increased in production equipment to reduce residual VCl (which is subsequently recovered) while, at the same time, monitoring potentially affected resin characteristics such as heat stability, dryblend time, contamination, and fisheyes. Adolph A. Peterson Notebook Reference: Process Studies Notebook No. 9114 4 - DER, pp 29 - 37 Appendix: Three tables Six figures Two procedures * ucc 041532 TABLE I OVEN DRIED SAMPLES OF VACUUM STRIPPED PRODUCTION QSAN Sample Number 1 2 3 4 7 8 9 10 11 12 uns tripped Stripping time (Minutes) 15 60 15 60 15 60 15 60 15 60 Temperature CC) 27 25 50 50 22 22 50 50 80 80 V acuum (inch Ha) 26.9 28.7 24.2 26. 0 15. 0 15. 0 15.0 15.0 15.0 15.0 Residual VC1 (ppm) Nil 39 10 Nil 22 12 23 ( Nil Nil Nil Nil %% m ucc 041533 TABLE II FIRST VALID TEST OF RESIDUAL VCL AS FUNCTION OF STRIPPING CONDITIONS Sample Number Stripping time ? (Minutes) Temperature (*C) Vacuum eBidual VC1 jinctTHg) IfrgV (fom) tu : c CJr <yp .------ 1 * 60 MO - 2 Iro 3 NO 4 A/0 _____ 5 fU W) ____ 6 AO ------ 7 15 %15 60 15 15 60 i v.yv' 9-t. 0U? 22.377 /07. vo IS, lS D- 8? iU- -- 8 NO r*-- 9 /I/O v 10 15 3*V.( 60 OV? 60 . tvvs? / Unstripped sample of 165 micron 18 22 i 23 24 _ : 53 46 _i5-- ) 8Q VO <JoJ c U4 29-3 28. 5 it.ot 0 a7*.CJ 15.0 15.0 26.6 w-ir 15.0 15.0 26.0 15. 0 2269 3381 3245 3193 2672 1603 1803 ; 124 1357 163 3398 ItiM 32. 2. *I`C nr nr */-r ti.r nr* *V<3 1A 60 MO fit. 7 2A 3A 15 15 /W 4A 60 IvO 5A 15 T7-1- "y*3 6A ' A/0 7A 15 60 /m-A 8A 15 f/vT 9A 10A 60 ion. <60 Unstripped sample of 100 micron 18 2226 ; _2*,,. 51 46 A _52~ 80 <53 80 N 29.3 28. 5 15.0 15.0 15. 0 26.6 15.0 15.0 26.0 15. 0 2234 3475 4177 3765 2524- 1389' 1652 -- 69 1041 138 4446 Ucc 041534 TABLE III SECOND VALID TEST OF RESIDUAL VCI AS FUNCTION OF STRIPPING CONDITIONS Sample Number Stripping time c Temperature (Minute a) .. CC) M3 M) NO 1 60 IVUS 60 2 15 N%is 60 3 60 T-rt-l 75 4 60 SU'.lf, 90 5 15 90 6 15 JP9-I 75 Unstripped sample of 100 micron QSAN v Vacuum (inch Hg) Residual VCI . '4> --lBPm)-- hc 15 m 15 15 9 i'U-f 9 15 1161 2021 218 2 62 305 5100 Of Cue at) 1A 2A M? 3A AOP 4A /VO 5A 60 "?> 90 15 90 15 vfV1 75 60 >?1 -/ 75 60 60 9 10 9 trace 15 304 15 199 15 2075 S E M I-l.O G A R IT H M IC 4 5 4 3 C Y C L E S X 7 ft p I v r S IO N M N l M* U ftEM I-LO CARITHM tC 4 6 5 4 9 3 Tjf uce 041s47 STt/fP'A'f STUPf EXPERIMENT TO DETERMINE OPTIMUM STRIPPING CONDITIONS TO REDUCE VC1 RETAINED IN THE RESIN A. A. Peterson 5-29-74 On Thursday, May 30, we plan to make the following experiment on normal production QS&N: 1) Sample the #1 BDT of the production unit after it has been vented to the 3 paig vent header. The fresh air mask shoud be utilized during sampling to minimize exposure to VC1, Take a 5 gallon sample from the BDT pump discharge. This sample should be tightly closed to minimize further loss of VC1 and to minimize exposure . 2) Take the sample to the lab for stripping tests. 3J) Use the following equipment for stripping tests: Vacuum pump, 1 liter round bottom flask, trap flask to prevent entrainment carryover, vacuum gauge for round bottom flask* heating mantle for round bottom flask, thermometer to measure temperature in round bottom flask, necessary tubing and support equipment. Use the laboratory notebook entitled Process Studies to record the data. 4) Each time a sample is removed from the 5 gallon drum, be sure to shake to insure a faijly contant slurry concentration for each sample to be stripped. ' 5) Each sample of slurry to be stripped should be approxiamately 0. 5 liter. 6) Place the 0. 5 liter sample into the round bottom flask and stopper with a three hole stopper to permit evacuation, temperature measurement, and vacumm readings. 7) Perform the stripping at the following sets of conditions ( one sample for each) lib a) Room temperature for 15 minutes at the boiling point b) Room temperature for 1 hour at the boiling point c) 50 C for 15 minutes at the boilng point d) b8<l9tAlfe49>e 50C for 1 hour at the boiling point ) 80 C. for 15 minutes at the boiling point f) 80 C. for 1 hour at the boiling point g) R peat a thru f at 15 inches of vacuum if this is less than the boiling point 8) Dry each sample ( approxiamately 200 gms of dry resin ) at M 40 C overnight in the oven 9) D liver each sample to Bob Arnold for analysis of VC1 content. We will use this or a modified procedure on several batches of resin made in the pilot plant in which we will vary resin particle size and porosity to determine the effects of the variables on the effectiveness of resin4 stripping. " ucc 041542 6-10-74 CONTINUED STRIPPING STUDIES, SUSPENSION RESINS Dan O'Daniel J. C. Chaty As can be seen from the attached graphs, the most significant variable affecting residual VC1 in the previous study appears to be the temperature. I propose the following more detailed study to pinpoint the effect: SAMPLE TEMP VACUUM TIME Production QSAN 60, 75, 90 C 15 inches Hg * 15, 60 minutes PILOT PLANT 100 micron QSAN 60, 75, 90C m 15 inches Hg 15, 60 minutes This will be six samples plus the unstripped sample for each type <flr a total of 14 samples to be submitted to the lab . We will begin this work on Tuesday, June 11. Adolph ucc 041543 DISTRIBUTION LIST TO: Dr. W. B. Ackart - BB Mr. R. M. Arnold Dr. J. C. Chaty S Mr. M. E. Eisenhour Mr. J. W. Fields m Mr. R. L. Frantz Mr. R. J. Hanna - Tech Center Mr. F. Li. Johnson ^ Mr. R. P. Keefe Dr. W. R. Manning - Tech Center Mr. G. T. Scott - NYO (31) Mr. R. W. SesLer Mr. O. A. Shelton Dr. A.B. Steele - NYO (28) Mr. G. F. Tacquard Mr. RN. Wheeler - South Charleston File - 10 - Bldg. 133 ucc 041544 CHEMICALS AND PLASTICS . o* <71. TtXA crTV. TEXAS 77MO Id (NAME) COMPANY LOCATION m I.l.'4 to Mr, J. C. Akins ^ Mr, M. E. Eisenhour^ Mr. R. L. Frantz Mr. G. T. Pyle Mr. R. W. Sesler Mr. 0. A. Shelton Mr. O. F. Tacquard * date * May 14, 1974 ' ` "K `. ,> ' ^ subject Reduction of Residual " VCM in Suspension Resin ' ' * * ` 'V a- Attached is the program baaed on objectives agreed to in the meeting held on May 9, 1974 on the above subject. The objectives of the program are as follows: I. . The overall objective is to reduce the residual VCM to the minimum achievable with present equipment and recipes without loss of production. Specific Objectives: A. To determine the VCM levels as related to process variables and pertinent resin properties. B. To determine the function of temperature on residual VCM in resin which has been blended. C. To determine the effect of blending on stratification of resin.' The program lists the steps, the initials of the person accountable, and a completion date. With the exception of Mr. Akins, the program has been ' discussed with the person accountable and has his understanding and acc ptance. In general, a two-week program is planned with data on products made during that period. The program can be extended to include additional products if needed. ^ FLJ/st Attachments /f> R. M. Arnold OCC 041545 (3 I. Overall Objective Reduce the VCM in the suspension resin to minimum level achievable with present equipment and recipes without loss of production. How 1. Achieve maximum vacuum stripping capability with equipment available (OAS, /9/74) ,, ,2. Achieve consistent stripping conditions from shift to shift (OAS, 5/17/74. ** 3. Operate dryers at maximum outlet temperature as consistently as possible (GTP, 5/10/74) 4. Use bins with blending nozzles whenever available and blena for two hours at maximum air flow (GTP, 5/17/74) 4 5. Measure and record air flow to blenders (GTP, 5/17/74) A. Specific Program Objective Determine the VCM levels in the resin as related to process variables and pertinent resin properties in keeping with overall objective above. How l. Record process variables a. Put in necessary instruments to measure vacuum at vacuum strippers (OAS, 5/17/74) b. Record stripping conditions and vacuum obtained on log sheet as each autoclave is stripped (OAS, 5/17/74) c. Record dryer outlet temperatures hourly on log sheets next to bin being filled (GTP, 5/17/74) Z. Determine VCl levels in resin on (a) at least 50% of blends (RMA 5/20 - 6/3/74) (1) boxes (2) each compartment on HC's (b) retain samples in capped glass bottles until program complete (RMA, 5/20 - 6/3/74) ucc 041546 3. Accumulate data as indicated on attached data sheet for each resin type (FLJ, 6/7/74) 4. Data will include particle size and dryblend from quality control analysis. Dryblend data will be run once/shift per resin type on single bin - no composites. (JCA, 5/20 - 6/3/74) *" 5. Determine correlation of VCl with process variables and/or resin properties (FLJ, RMA, 6/10/74) B. Specific Frograun Objective e Determine the function of temperature on residual VCM in resin which has been blended. How 1. Use bins (604, 605) in Bldg. 178 where heated air is available (GTP, 5/20/74) 2. Install instrumentation to measure air flow to bins in Bldg. 178 (GTP, 5/20/74) 3. Check air volumes to bins to determine if equal (and record) during test (RMA, 5/20 - ) 4. Blend for 4 hours - sample initially and hourly. Determine residua. VCM (RMA, 6/7/74) 5. To determine effect of temperature directly run one bin without heated air and second with heated air (RMA, 6/17/74) 6. Review and report results (FLJ, RMA, 6/10/74) C. Specific Program Objective Determine the effect of blending on stratification of resin. How 1. Determine if stratification occurs by running screen analysis on "beginning, middle, and end" sampLeB taken as van box is loaded. (RMA, 6/7/74) .2 Review and report results (FLJ, RMA 6/10/74) ucc 041547 L047-A / >i `cr r