UOP 578-2011 Automated Pore Volume and Pore Size Distribution of Porous Substances by Mercury Porosimetry.pdf

1、 IT IS THE USERS RESPONSIBILITY TO ESTABLISH APPROPRIATE PRECAUTIONARY PRACTICES AND TO DETERMINE THE APPLICABILITY OF REGULATORY LIMITATIONS PRIOR TO USE. EFFECTIVE HEALTH AND SAFETY PRACTICES ARE TO BE FOLLOWED WHEN UTILIZING THIS PROCEDURE. FAILURE TO UTILIZE THIS PROCEDURE IN THE MANNER PRESCRIB

2、ED HEREIN CAN BE HAZARDOUS. MATERIAL SAFETY DATA SHEETS (MSDS) OR EXPERIMENTAL MATERIAL SAFETY DATA SHEETS (EMSDS) FOR ALL OF THE MATERIALS USED IN THIS PROCEDURE SHOULD BE REVIEWED FOR SELECTION OF THE APPROPRIATE PERSONAL PROTECTION EQUIPMENT (PPE). COPYRIGHT 1984, 2002, 2011 UOP LLC. All rights r

3、eserved. Nonconfidential UOP Methods are available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, USA. The UOP Methods may be obtained through the ASTM website, www.astm.org, or by contacting Customer Service at serviceastm.org, 610.832.9555 FAX, or

4、610.832.9585 PHONE. Automated Pore Volume and Pore Size Distribution of Porous Substances by Mercury Porosimetry UOP Method 578-11 Scope This method is for determining the pore size distribution and pore area of materials by mercury intrusion. Total pore volume (intrusion volume), total pore area, b

5、ulk (piece) density and apparent (skeletal) density are also determined. At the maximum pressure of 413,700 kPa (60,000 psia), pores as small as 0.003 m are filled. This method is applicable to materials which are essentially non-compressible at the pressures attained during analysis. The sample mus

6、t also be non-wetting and non-reactive with mercury, and not larger than a right circular cylinder having 25-mm diameter with a length of 25 mm. References Instruction Manual, supplied with instrument UOP Method 999, “Precision Statements in UOP Methods,” www.astm.org Outline of Method Previously ou

7、tgassed samples are weighed into penetrometers and placed in the low-pressure ports where they are evacuated and automatically filled with mercury. Due to the unique non-wetting property of mercury, it will not enter pores or capillaries except under pressure. Filling pressures between 3.4 kPa (0.5

8、psia) and atmospheric pressure can be used depending on whether larger pores are of interest. The samples are then removed from the low-pressure ports and placed in the high pressure chambers. Using high-pressure fluid, the mercury is forced into the pores at incrementally increasing pressure to mea

9、sure the intrusion data. Pressure is increased to a maximum of 413,700 kPa (60,000 psia). Pore volume readings are taken at predetermined pressures. If extrusion data, a measure of the mercury coming out of the pores as the pressure is reduced, is desired, pore volume readings are also taken as the

10、pressure is reduced to atmospheric. A maximum of 2,500 pressure points can be chosen for the intrusion/extrusion curve. The standard pressure points and their corresponding pore diameters are listed in Table 1. Other pressure tables are available for use based on the submitters needs or the specific

11、 pore ranges needed to be highlighted. Apparatus References to catalog numbers and suppliers are included as a convenience to the method user. Other suppliers may be used. 2 of 12 578-11 Balance, readability 0.0001 g, chamber accessible from both top and sides, OhausTM Analytical Plus Series, Model

12、AP 310, Fisher Scientific, Cat. No. 01-920-80 Desiccator, with porcelain plate, 250-mm ID, Fisher Scientific, Cat. No. 08-615B Dishes, Coors, shallow form porcelain, 80-mm diameter, 50-ml capacity, Fisher Scientific, Cat. No. 08-693B Gauge, vacuum, range 0-0.001 kPa (0-250 mm Hg), Fisher Scientific,

13、 Cat. No. 11-282A, used with vacuum oven Gloves, Kelkave Autoclave, temperature resistant up to 288C (550F), length 11 inches, size large, Fisher Scientific, Cat. No. 19-013-586 Hood, laboratory Mercury intrusion porosimeter, supplied with data terminal and printer, Micromeritics, Autopore IV. This

14、method is written assuming the use of the specified porosimeter. If other equipment is used, adapt the method accordingly. Oven, vacuum, maximum temperature 200C, maximum vacuum 0.01 kPa, chamber 20 x 20 x 30 cm, PrecisionTM, Model 19, Fisher Scientific, Cat. No. 13-264A Penetrometers, powder sample

15、s, 3-mL sample volume, 0.39-mL intrusion volume, Micromeritics, Cat. No. 942-61714-00, several required. Other penetrometers, with larger sample volumes and intrusion volumes are also available. Penetrometers, solid samples, 3-mL sample volume, 0.39-mL intrusion volume, Micromeritics, Cat. No. 942-6

16、1713-00, several required. Other penetrometers, with larger sample volumes and intrusion volumes are also available. Pump, vacuum, 91-L/min, WelchTM Duo SealTM, Model 1405, Fisher Scientific, Cat. No. 01-099 Regulator, nitrogen, single-stage, Matheson Gas Products, Model 1-580 Software, Autopore IV

17、9500, Version 1.09, Micromeritics Thermometer, for measuring ambient temperature, Fisher Scientific, Cat. No. 15-060-274 Tongs, stainless steel, 23-cm, Fisher Scientific, Cat. No. 15-186 Reagents and Materials References to catalog numbers and suppliers are included as a convenience to the method us

18、er. Other suppliers may be used. Dessicant, Drierite, Fisher Scientific, Cat. No. 07-578-3A Detergent, Alconox, Fisher Scientific, Cat. No. 50821294 Fluid, high pressure, Micromeritics, Cat. No. 920-16001-00 Gas, dry, air or nitrogen Gloves, BestTM NitriSolveTM Nitrile, Fisher Scientific, Cat. No. 1

19、1-395 series Grease, stopcock, ApiezonTM H, Micromeritics, Cat. No. 004-16007-00 Grease, Dow CorningTM, high vacuum, Fisher Scientific, Cat. No. 14-635-5D Mercury, quadruple distilled, Bethlehem Apparatus. Caution: see Precaution. 3 of 12 578-11 Nitrogen, gas, 99.98% minimum purity Procedure The ana

20、lyst is expected to be familiar with general laboratory practices, the technique of mercury porosimetry, and the equipment being used. Calibrate the instrument as outlined in the Instruction Manual. Instrument operation must be thoroughly understood before any attempt is made to analyze samples. Ent

21、er the standard pressure points from Table 1. This Procedure is written assuming the use of the equipment specified under Apparatus. If other equipment is used, adapt the procedure accordingly. Although the use of metric units is preferred, the pressure units used by the listed porosimeter are psia,

22、 and thus, are listed in Table 1. Table 1 Standard Pressure Points and Corresponding Pore Diameters (Contact Angle = 130, Surface Tension , = 485 dynes/cm) Pressure, psia Pore Diameter, m Pressure, psia Pore Diameter, m 8.9 20.0000 4486.0 0.0400 18.0 10.0000 5127.0 0.0350 31.0 5.8333 5981.0 0.0300 4

23、5.0 4.0000 6188.0 0.0290 103.0 1.7500 6409.0 0.0280 150.0 1.2000 6646.0 0.0270 199.0 0.9000 6902.0 0.0260 239.0 0.7500 7178.0 0.0250 299.0 0.6000 7477.0 0.0240 359.0 0.5000 7802.0 0.0230 513.0 0.3500 8156.0 0.0220 598.0 0.3000 8545.0 0.0210 665.0 0.2700 8972.0 0.0200 748.0 0.2400 9444.0 0.0190 854.0

24、 0.2100 9969.0 0.0180 1025.0 0.1750 10555.0 0.0170 1196.0 0.1500 11215.0 0.0160 1495.0 0.1200 11963.0 0.0150 1794.0 0.1000 12817.0 0.0140 1889.0 0.0950 13803.0 0.0130 1994.0 0.0900 15337.0 0.0117 2111.0 0.0850 16313.0 0.0110 2243.0 0.0800 17944.0 0.0100 2393.0 0.0750 19938.0 0.0090 2563.0 0.0700 224

25、30.0 0.0080 2761.0 0.0650 25634.0 0.0070 2991.0 0.0600 29907.0 0.0060 3263.0 0.0550 35888.0 0.0050 3589.0 0.0500 44860.0 0.0040 3988.0 0.0450 60000.0 0.0030 Calibration of Penetrometer Volume To calibrate a penetrometer, simply perform a low pressure analysis with no sample. This fills the penetrome

26、ter with mercury so that the volume can be determined. Up to four penetrometers can be 4 of 12 578-11 calibrated at one time, utilizing all four low-pressure ports. Clean, grease, and seal each penetrometer according to the instructions in the manual. 1. Weigh the empty penetrometers to the nearest

27、0.0001 g and record the weight. See Appendix A in the manual for the penetrometer volume calibration form. 2. Place a penetrometer into each of the low-pressure ports. 3. Create and select sample file for analysis following manufacturers instructions. 4. Remove the mercury filled penetrometers accor

28、ding to manual instructions, and reweigh to the nearest 0.0001 g, recording the weight. 5. Determine the ambient temperature. 6. Calculate the volume of the penetrometer, to three decimal places, using Equation 1: V = D AB (1) where: A = mass of empty penetrometer, g B = mass of penetrometer filled

29、with mercury, g D = density of mercury at ambient temperature, g/ml. See Table 2. Extrapolate between listed temperatures as needed. V = volume of penetrometer, mL This procedure must be performed three times for each penetrometer. Use the average volume of the empty penetrometer in all further calc

30、ulations involving that penetrometer. This must be done only once if all the parts of the penetrometer are kept together and a record of the results is maintained. Penetrometer volumes for the three replicates must all be within 0.01 mL. If greater deviation occurs, recheck the equipment and techniq

31、ue, and make additional calibrations until the required repeatability is obtained on three consecutive calibrations. Table 2 Density of Mercury C g/mL C g/mL C g/mL C g/mL 18.0 13.5512 23.2 13.5384 25.2 13.5335 27.2 13.5286 19.0 13.5487 23.4 13.5379 25.4 13.5330 27.4 13.5281 20.0 13.5462 23.6 13.537

32、4 25.6 13.5325 27.6 13.5276 21.0 13.5438 23.8 13.5369 25.8 13.5320 27.8 13.5271 22.0 13.5413 24.0 13.5364 26.0 13.5315 28.0 13.5266 22.2 13.5408 24.2 13.5359 26.2 13.5310 29.0 13.5242 22.4 13.5403 24.4 13.5354 26.4 135305 30.0 13.5217 22.6 13.5399 24.6 13.5350 26.6 13.5301 31.0 13.5193 22.8 13.5394

33、24.8 13.5345 26.8 13.5296 32.0 13.5168 23.0 13.5389 25.0 13.5340 27.0 13.5291 33.0 13.5144 Sample Preparation 1. Place enough sample in a shallow porcelain dish to run this test, noting what sample is in which dish. 2. Place the dishes in a vacuum oven and evacuate down to at least 0.04 kPa. 3. Heat

34、 the oven to 150 5C and allow samples to outgas for a minimum of 8 hours. 5 of 12 578-11 4. Release the seal on the vacuum oven allowing it to come to atmospheric pressure with dry air or dry nitrogen. 5. Remove the hot dishes and place in a desiccator to cool to room temperature. Samples should rem

35、ain in the desiccator until they can be analyzed. Sample Analysis Referring to the instrument manual, determine the approximate amount of sample required and the appropriate calibrated penetrometer. 1. Apply Apiezon H stopcock grease to the empty penetrometer, but do not seal. 2. Weigh the complete

36、disassembled penetrometer to the nearest 0.0001 g and record the weight. 3. Weigh and record the predetermined amount of sample from the cooled dishes. Fill the penetrometer with the weighed sample, making sure not to get any sample in the penetrometer grease. 4. Seal the cap assembly. 5. Place the

37、penetrometer in one of the four low pressure ports, add a spacer behind each penetrometer if needed, making sure to put rods in all unused ports if four samples are not being analyzed. Cover with capacitance transducers. 6. Make sure that analysis conditions, penetrometer properties, and report opti

38、ons have been preset for your requirements. If not, refer back to the instruction manual for entering these steps. 7. Make sure that the mercury reservoir has been filled with clean mercury. 8. Select File, Open, and Sample information. Check that the sequence file name is the next determined number

39、 and click OK, then Yes, to create a sample file. Fill in the appropriate sample information, choose the appropriate analysis condition, Penetrometer properties and Report option for each sample being analyzed. When this information is entered select the unit number, Low pressure analysis, next, and

40、 the proper sample information from the list for each port being analyzed. When this has been completed, press Start to start the Low pressure analysis. 9. After completion of the low pressure run, remove each filled penetrometer, weigh in an upright position to the nearest 0.0001 g, and record the

41、weight. 10. Place the full weighed penetrometer in one of the two high-pressure ports. Tighten down each chamber so oil fills the top vent valve. If more than one sample was run at low pressure, repeat this procedure on another sample in the second high pressure port. If more than two samples were r

42、un at low pressure, leave the remaining samples on the low pressure ports until a high pressure port becomes available. 11. Start the high pressure analysis, select the unit number, High pressure analysis, Browse, find the appropriate sample for each port, enter the penetrometer plus mercury weight

43、and choose Start to analyze samples. Remember to tighten the vent valve caps when instructed to do so. 12. When the high pressure analysis is complete the data will have to be reviewed. Select Report, Start report, find the appropriate sample file number or numbers and click OK to review report 13.

44、Repeat above steps for other samples. 6 of 12 578-11 Calculations All calculations are performed by the computer via Version 1.09 software and printed out by the terminal. See the Appendix for examples of the reports and explanations of terms. The following equations are used and are given here for

45、information only. Assuming a cylindrical pore model, the relationship of the diameter of the pore to the pressure required to force mercury into it is described by the Washburn Equation (Equation 2): P = Dcos4 (2) where: D = diameter of the pore, m P = pressure, psia = surface tension of mercury, dy

46、nes/cm = contact angle between the mercury and the material being tested, degrees Assuming a contact angle of 130 to be a reliable value for a wide range of materials, and 485 dynes/cm to be the most common value for the surface tension of mercury, the above equation reduces to Equation 3: D = P180

47、3) where: D = diameter of the pore, m P = pressure, psia Precaution Mercury and mercury vapors are known health hazards. An exhaust and ventilating system is built into the instrument. Exercise caution to prevent spills when weighing and transporting filled penetrometers. It is mandatory that penet

48、rometers be cleaned in a hood. All used mercury must be disposed in an environmentally safe manner according to local regulations. Precision Precision data were obtained using UOP Method 999. Repeatability and Site Precision A nested design was carried out for determining the intrusion volume of a c

49、atalyst with three analysts. Each analyst carried out tests on two separate days, performing two tests each day. The total number of tests performed was 12. The precision data are summarized in Table 3. Two tests performed by the same analyst on the same day should not differ by more than the repeatability allowable difference with 95% confidence. Two tests performed in one laboratory by different analysts on different days should not differ by more than the site precision allowable difference with 95%