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. SAFETY DATA SHEETS (SDS) OR EXPERIMENTAL SAFETY DATA SHEETS (ESDS) FOR ALL OF THE MATERIALS USED IN THIS PROCEDURE SHOULD BE REVIEWED FOR SELECTION OF THE APPROPRIATE PERSONAL PROTECTION EQUIPMENT (PPE). COPYRIGHT 1966, 1988, 1993, 2014 UOP LLC. All rights reserved. Nonco
3、nfidential 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 610.832.9585 P
4、HONE. Apparent Bulk Density of Catalyst Particles UOP Method 294-14 Scope This method is for determining the apparent bulk density (ABD) of loosely packed spherical catalyst particles with an average particle diameter of 1.6- to 3.2-mm ID. It is also applicable to extruded catalyst particles having
5、a maximum diameter of 3.2 mm, a maximum average length of 9.5 mm, and a maximum individual length of 16 mm. Apparent bulk density is the mass per unit volume of the particulate material. Reference UOP Method 999, “Precision Statements in UOP Methods,” www.astm.org Outline of Method The sample is pou
6、red into a weighed and volume-calibrated cylinder. The catalyst is leveled to the top of the cylinder and weighed. ABD is calculated by dividing the mass of the catalyst by the volume of the cylinder. Apparatus References to catalog numbers and suppliers are included as a convenience to the method u
7、ser. Other suppliers may be used. Balance, readable to 0.01-g Beaker, 250-mL, VWR, Cat. No. 89000-204 Cover, cylinder, flat plastic, glass, or other transparent and non-porous material, approximately 50-mm (2-inches) square, local supply Cylinder, graduated, glass, 250-mL, 38-mm ID, Fisher Scientifi
8、c, Cat. No. 08-555E, cut down to the 100-mL mark and fire polished, “weighing cylinder.” A cylindrical crucible, 100-mL, 39-mm diameter, 91-mm height, CoorsTek, Cat. No. 65539, is also suitable Funnel, powder, polypropylene, 75 to 80-mm top diameter, Fisher Scientific, Cat. No. 10-500-1 Ring, suppor
9、t, iron, with screw clamp, slotted, VWR, Cat. No. 60130-004 Spatula, 152-mm straight-edge blade, VWR, Cat. No. 82027-462 Support, rectangular base, steel rod, VWR, Cat. No. 60110-222 2 of 4 294-14 Thermometer, -l to 51 C range, 0.1 C subdivisions, partial immersion, spirit filled, VWR, Cat. No. 6122
10、2-624 Timer/stopwatch, VWR, Cat. No. 98000-186 Tray, polypropylene, medium-deep form to catch scattered particles, large enough to accommodate ring support, Fisher Scientific, Cat. No. 13-359-20A Reagents and Materials References to catalog numbers and suppliers are included as a convenience to the
11、method user. Other suppliers may be used. References to water mean deionized or distilled. Tissues, Kimwipes, Fisher Scientific, Cat. No. 06-666A Water, deionized or distilled Procedure The analyst is expected to be familiar with general laboratory procedures and the equipment being used. Dispose of
12、 used supplies and samples in an environmentally safe manner according to applicable regulations. Volume Calibration of the Weighing Cylinder The weighing cylinder must be calibrated for volume initially and on a periodic basis thereafter to ensure accurate analyses. For a certified calibration, the
13、 weighing cylinder is sent out to a certified calibration laboratory, e.g., The Calibration Solution, for calibration. Alternatively, if a certified calibration is not necessary, the calibration may be done in house by filling the cylinder with water and weighing it as described below. For in house
14、calibration only: 1. Weigh the dry cylinder and cylinder cover to the nearest 0.01 g. 2. Fill the cylinder to the brim with water. Dislodge any bubbles adhering to the cylinder walls by gently tapping the sides, being careful not to spill the water. Add additional water, if necessary, without introd
15、ucing bubbles. 3. Touch one edge of the cover to the rim of the cylinder. Lower the cover onto the cylinder while carefully excluding all air bubbles from below the cover. Dry the outside of the cylinder carefully. 4. Weigh the filled cylinder and cover to the nearest 0.01 g. 5. Remove the cylinder
16、from the balance and determine the temperature of the water to the nearest 0.1 C. Determine the density of the water at the measured temperature from the Figure or other source. Calculate the exact volume of the cylinder, using Equation 1: C = D EW (1) where: C = calibrated volume, mL E = mass of em
17、pty cylinder and cover, g D = density of water at measured temperature, g/mL W = mass of cylinder and cover containing water, g 3 of 4 294-14 Determination of ABD 1. Record the mass of the dry, empty calibrated weighing cylinder without the cover. 2. Place the ringstand with the ring in the tray to
18、catch bouncing particles. 3. Support the funnel on the ringstand so the bottom of the stem is approximately 115 mm above the top of the cylinder. If at least two thirds of the particles do not enter the cylinder from this height, the distance may be reduced until greater than two thirds of the catal
19、yst particles enter the cylinder. 4. Over a time period of 45 to 60 seconds, pour 150 mL of a representative sample, at a uniform rate, onto the sides of the funnel using a circular motion. Allow the catalyst to fill the cylinder until it overflows. 5. Without tapping, shaking or otherwise disturbin
20、g the cylinder, scrape off the excess catalyst with a straight-edged spatula. Use a sawing motion to prevent packing of the catalyst in the cylinder and to avoid removing catalyst below the plane of the cylinder rim. 6. Weigh the full cylinder to the nearest 0.01 g. 7. Pour the catalyst collected in
21、 the cylinder and tray into a beaker and repeat the analysis two more times. 8. If the highest and lowest values differ by more than 1%, repeat the analysis twice more and discard the one suspected result. Calculations Calculate the average apparent bulk density (ABD) for the three replicates and re
22、port to 3 decimal places, using Equation 2: ABD, g/mL = Cn)TM(n1i=(2) where: C = calibrated volume of cylinder, from Equation 1, mL M = mass of cylinder plus catalyst for each individual test, g n = number of individual tests T = tare mass of empty cylinder, g Precision Precision statements were det
23、ermined using UOP Method 999, “Precision Statements in UOP Methods.” Repeatability, Site Precision, and Reproducibility A nested design was carried out for determining ABD in five laboratories, by two analysts in each laboratory, with each analyst performing analyses on two separate days, performing
24、 two analyses each day for a total of 40 analyses. Using a stepwise analysis of variance procedure, the within-day, within-lab, and between-lab estimated standard deviations (esd) were calculated at the concentration means listed in the Table. Two analyses performed in one laboratory by the same ana
25、lyst on the same day should not differ by more than the repeatability allowable differences shown in the Table with 95% confidence. Two analyses performed in one laboratory by different analysts on different days should not differ by more than the site precision allowable differences shown in the Ta
26、ble with 95% confidence. Two analyses performed in different laboratories by different analysts on different days 4 of 4 294-14 should not differ by more than the reproducibility allowable differences shown in the Table with 95% confidence. The data in the Table represent short-term estimates of the
27、 repeatability of the method. When the test is run routinely, the use of a control standard and a control chart is recommended to generate an estimate of long-term repeatability. Table Repeatability, Site Precision, and Reproducibility, g/mL Repeatability Site Precision Reproducibility Catalyst Mean
28、 Within- Day esd Allowable Difference Within- Lab esd Allowable Difference Between- Lab esd Allowable Difference Extruded A 0.669 0.0024 0.007 0.0061 0.019 0.0072 0.022 Extruded B 0.808 0.0039 0.011 0.0051 0.016 0.0113 0.051 Extruded C 1.037 0.0072 0.021 0.0156 0.050 0.0195 0.068 Spherical A 0.319 0
29、.0004 0.001 0.0016 0.006 0.0024 0.010 Spherical B 0.554 0.0009 0.003 0.0014 0.005 0.0030 0.014 Spherical C 0.714 0.0010 0.003 0.0028 0.009 0.0044 0.017 Time For Analysis The elapsed time and labor requirements for both spherical and extruded catalyst particles are identical, 0.6 hour. Suggested Supp
30、liers CoorsTek, 4545 McIntyre St., Golden, CO 80403, USA, 1-303-277-4038, Fisher Scientific, 300 Industry Dr., Pittsburgh, PA 15275, USA, 1-412-490-8300, The Calibration Solution, 9865 N. Alpine Rd., Machesney Park, IL 61115, USA, 1-815-877-0080, VWR International, 1310 Goshen Parkway, West Chester, PA 19380, USA, 1-610-431-1700, Figure Temperature, C vs. Density of Water, g/mL Water Density = 1.000 g/mL at 3.98 C
