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 1965, 1987, 2014 UOP LLC. All rights reserved. Nonconfiden
3、tial 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 PHONE.
4、Apparent Bulk Density of Fluid Cracking Catalyst UOP Method 254-14 Scope This method is for determining the apparent bulk density (ABD) of loosely packed fluid cracking catalyst in a particle size range of less than 200 m diameter. Apparent bulk density is the mass per unit volume of the particulate
5、 material. Reference UOP Method 999, “Precision Statements in UOP Methods,” www.astm.org Outline of Method The sample is poured 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
6、 volume of the cylinder. Apparatus References to catalog numbers and suppliers are included as a convenience to the method user. Other suppliers may be used. Balance, readable to 0.01 g Beaker, 250-mL, VWR, Cat. No. 89000-204 Brush, balance, antistatic, VWR, Cat. No. 15551-016, Cylinder cover, flat,
7、 plastic, glass or other transparent and non-porous material, approximately 25-mm (1-inch) square, local supply Cylinder, graduated, glass, 50-mL, 13-mm ID, Fisher Scientific, Cat. No. 08-555C, cut down to the 25-mL mark and fire polished, “weighing cylinder.” A cylindrical crucible, 20-mL, 28-mm di
8、ameter, 40-mm height, CoorsTek, Cat. No. 65535, is also suitable Funnel, powder, polypropylene, 75 to 80-mm top diameter, Fisher Scientific, Cat. No. 10-500-1 Ring, support, iron, with screw clamp, slotted, VWR, Cat. No. 60130-004 Spatula, 152-mm straight-edge blade, VWR, Cat. No. 82027-462 Support,
9、 rectangular base, steel rod, VWR, Cat. No. 60110-222 2 of 4 254-14 Thermometer, -l to 51 C range, 0.1 C subdivisions, partial immersion, spirit filled, VWR, Cat. No. 61222-624 Timer/stopwatch, VWR, Cat. No. 98000-186 Tray, polypropylene, medium-deep form to catch scattered particles, large enough t
10、o 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 method user. Other suppliers may be used. References to water mean deionized or distilled. Tissues, Kimwipes, Fisher Scientific,
11、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 used supplies and samples in an environmentally safe manner according to applicable regulations. Volume Calibration of the Weigh
12、ing 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 weighing cylinder is sent out to a certified calibration laboratory, e.g., The Calibration Solution, for calibration. Alternativ
13、ely, 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 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
14、. 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 introducing bubbles. 3. Touch one edge of the cover to the rim of the cylinder. Lower the cover onto the cylinder while carefully exclu
15、ding 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 from the balance and determine the temperature of the water to the nearest 0.1 C. Determine the density of the water at the measu
16、red 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 empty cylinder and cover, g D = density of water at measured temperature, g/mL W = mass of cylinder and cover containing water, g 3
17、 of 4 254-14 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 catch bouncing particles. 3. Support the funnel on the ringstand so that the bottom of the stem is approximately 20 mm above the
18、 top of the cylinder. 4. Over a time period of 25 to 35 seconds, pour a representative sample of the catalyst, 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 disturbing the
19、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. Carefully brush the excess catalyst from the sides and base of the cylinder and weigh
20、the full cylinder to the nearest 0.01 g. 7. Pour the catalyst collected in 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 3%, repeat the analysis twice more and discard the one suspected result. Calculations Calcula
21、te the average apparent bulk density (ABD) for the three replicates and report 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
22、T = tare mass of empty cylinder, g Precision Precision statements were determined using UOP Method 999, “Precision Statements in UOP Methods.” Repeatability and Site Precision A nested design was carried out for determining ABD on two samples by two analysts in one laboratory, with each analyst perf
23、orming analyses on three separate days, performing two analyses each day for a total of 24 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 an
24、alyses performed in one laboratory by the same analyst 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 si
25、te precision allowable differences shown in the Table with 95% confidence. 4 of 4 254-14 The data in the Table represent short-term estimates of the 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 o
26、f long-term repeatability. Table Repeatability and Site Precision, g/mL Repeatability Site Precision Mean Within- Day esd Allowable Difference Within- Lab esd Allowable Difference 0.478 0.0017 0.006 0.0054 0.031 0.777 0.0027 0.009 0.0068 0.033 Reproducibility There is insufficient data to calculate
27、the reproducibility of the test at this time. Time For Analysis The elapsed time and labor requirements are identical, 0.2 hours. Suggested Suppliers 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
