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 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 1968, 1980, 2002, 2016 UOP LLC. All rights reser
3、ved. Nonconfidential UOP Methods are available from ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. 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,
4、 or 610.832.9585 PHONE. Heptane or Toluene Insoluble Matter in Petroleum Oils Using Vacuum Filtration UOP Method 614-16 Scope This method is for the determination of either heptane or toluene insoluble material in petroleum oils and is applicable to samples that are fluid at about 80C. This method c
5、overs the range of 0.01 to about 25 mass-% insolubles. Solid particulate materials interfere. More viscous or solid materials such as asphalts may be analyzed using this method but will require using a heated sonicating bath (up to 60C). The data provided by this method may be used as an index to co
6、king tendency of petroleum oils when considering their suitability as charge stocks to cracking or other processes. Outline of Method A weighed sample is dispersed in ambient temperature solvent, n-heptane or toluene, refluxed nominally at 80C for 2 hours, and filtered through a weighed glass microf
7、iber filter using vacuum. Samples that cannot be completely dispersed should not be analyzed by this method. The glass microfiber filter is dried at 100C and reweighed to obtain the weight of insoluble matter. Definition Asphaltenes are defined as the material present in oil fractions that is not so
8、luble in light paraffinic solvents. They are fine, powdery, black-brown solids and are polymeric materials spanning a wide range of molecular weights. Their chemical composition is quite complicated. They appear to be closely associated with high molecular weight semi-polar naphthenic materials that
9、 require extended digestion time for separation. The terms “heptane-insolubles“ and “toluene-insolubles” and “asphaltenes“ are often used synonymously. Apparatus References to catalog numbers and suppliers are included as a convenience to the method user. Other suppliers may be used, unless stated o
10、therwise. Balance, readable to 0.0001 g Clamp, for ring stand and sample cylinders. minimum opening 38.1-mm, VWR International, Cat. No. C6088-12 Clamp holder, for ring stand and clamp, VWR International, Cat. No. C6088-2 Condenser, glass 300mm with 24/40 fittings, VWR, Cat. No. KT431500-2430 2 of 7
11、 614-16 Cylinder, graduated, 250-mL, Fisher Scientific, Cat. No. 08-559EC Desiccator, to hold Petri dishes Dishes, Petri, borosilicate glass, 60-mm diameter, Fisher Scientific, Cat. No. 08-746A Electromantle with stirrer, 250ml, VWR, Cat. No. 33749-326 Filter apparatus (300-mL glass filter holder an
12、d 1-L filtering flask), VWR, Cat. No. KT953825-0000 Flask, round bottom 250-mL with 24/40 fitting, VWR, Cat. No. 80068-778 Flask, Erlenmeyer, narrow neck, 250-mL, with penny head, ground-glass, standard taper stopper, Fisher Scientific, Cat No. 10-100E Forceps, stainless steel, with flat, polished t
13、ips for handling filters, Millipore No. XX62 000 06 Hot plate, capable of 80C Oven, capable of operation at 100C Pipet, volumetric transfer, disposable, 2-mL, Fisher Scientific, Cat. No. 13-650-2C Pump, vacuum, Welch Director Direct Drive Pump, Fisher Scientific, Cat. No. 01-115-4 Ring stand, with r
14、ectangular base, 140- 229-mm with 610-mm rod, VWR International Cat. No. 470104-060 Stir bars, egg shape 1 inch by , VWR, Cat. No. 80062-140 Stir bar retriever, polyethylene, VWR, Cat. No. 80062-180 Tubing, Tygon, inch ID x inch OD, 1/16 inch wall, VWR International, Cat. No. 89403-882 Ultrasonic ba
15、th, heated, 1.5-L capacity, VWR, Cat. No. 89375-494 Wash Bottle, 500-mL, fluorinated HDPE, Fisher Scientific, Cat. No. 03-409-17B Reagents and Materials References to catalog numbers and suppliers are included as a convenience to the method user. Other suppliers may be used, unless stated otherwise.
16、 Dessicant, indicating Drierite, Fisher Scientific, Cat. No. 07-578-3A n-Heptane, 99% minimum purity, Honeywell Burdick there should be no sample left clinging to the bottom. If the sample is not completely dispersed, place the flask in the ultrasonic bath for 5 minutes. Use a ring stand and clamp t
17、o suspend the flask in the bath. Continue this procedure until the sample appears to be completely dispersed. The sample must be completely dispersed in the solvent or the test is invalid. 8. Place a stir bar in the flask, place flask into the electromantle and connect the condenser. Adjust the stir
18、 rate to maintain a moderate vortex, and set heating to achieve 80C. Temperature should be determined by heating a round bottom flask filled with solvent (toluene or heptane) by taking temperature with thermometer directly from flask after making set point adjustment and allowing temperature to equi
19、librate for 30 minutes. 4 of 7 614-16 As a best practice use of an over-temperature device that will cut power if any of the positions exceed 100C is recommended. 9. Pretreat filter paper for 30 minutes in 100C oven to remove moisture. Cool in desiccator. 10. Reflux the sample in the stirring heatin
20、g mantle for 2 hours. 11. Add about 180 mL of solvent, either n-heptane or toluene, to a 250-mL Erlenmeyer flask, place on hot plate and connect to condenser. Heat to approximately 80C. Approximately 25-30 mL of warm solvent will be used for the final rinse for each sample in steps 17 to 20. 12. Pla
21、ce a glass microfiber filter disc in a clean, dry, previously numbered Petri dish and weigh to the nearest 0.0001 g. Always handle the filter discs with smooth-tipped forceps. 13. Insert the base of the filter holder in the filtering flask. 14. Place the filter disc on the frit in the base of the fi
22、lter holder. 15. Attach the top (funnel) of the filter holder and clamp in place. 16. Apply a slight vacuum to the filter (see Note 2). 17. Turn off water flow to condensers. Remove the flask containing the sample from the heating mantle. Use a stir bar retriever to remove the stir bar from the samp
23、le flask. Rinse off the stir bar and retriever with the diluent solvent wash bottle. 18. Stopper and shake the flask, then pour the contents on the filter. If the amount of insoluble material is high, pour the contents on the filter in aliquots. 19. Rinse stopper into the funnel with diluent to coll
24、ect any residual sample. 20. When the level of the solution has receded to the throat of the funnel, rinse the funnel using hot (about 80C) heptane or toluene solvent, washing down the sides of the funnel to rinse any sediment onto the filter (see Note 3). CAUTION: Heptane and toluene have low flash
25、 points. 21. Continue with vacuum until the solids on the filter appear to be dry. 22. Unclamp the filter holder and gently remove the funnel. If the sediment is unusually heavy (greater than 40 to 50 mg) some of it may tend to cling to the throat of the funnel at the bottom where it meets the filte
26、r. Wash this material onto the filter using diluent solvent. 23. Examine the filter disc. The outer edge should be only lightly discolored if it was properly gripped by the holder. Wash the edge of the filter disc with a fine stream of solvent to remove any oil that may have seeped under the edge of
27、 the holder until the filter appears dry. 24. Turn off the vacuum and carefully transfer filter to the Petri dish in which the disc was originally weighed. 5 of 7 614-16 25. Discard the filtrate. 26. Place the dish containing the filter in the oven at 100C for 30 minutes to evaporate any residual so
28、lvent. 27. Remove the dish and filter, and cool in a desiccator until it reaches ambient temperature, approximately 30 to 45 minutes. 28. Reweigh to the nearest 0.0001 g. Note and report if any solid particles appear to be present on the filter. Calculations Calculate the concentration of heptane or
29、 toluene insolubles using the Equation. Insoluble Matter, mass-% = 100(G-T) L- M where: G = gross weight of dish, filter and residue, g T = tare weight of dish and filter, g L = weight of round bottom flask and sample, g M = weight of round bottom flask, g Note the solvent used when reporting insolu
30、bles results. For values from 0.01 mass-% to 10.0 mass-%, report to two decimal places. For values 10.0 mass-% and higher, report to one decimal place. Notes 1. Many waxy or viscous materials can be safely heated prior to transferring the desired amount into the flask. However, prolonged or overheat
31、ing can often cause oxidative or thermal polymerization of asphaltene precursors that result in a higher insolubles content. 2. Do not use more vacuum than what is absolutely necessary because evaporation of solvent and consequent chilling of the mixture may occur and cause the wax to precipitate. 3
32、. Rinsing the funnel is best done by using hot solvent. Do not allow the filter cake to become dry when rinsing as cracks may develop, allowing the solvent to flow through the cracks and not through the filter cake. This incomplete washing could cause high results. 4. Scope of the method allows for
33、determination of up to 25% insoluble material. Higher levels may be determined. However, precision has not been determined above the method scope. Precision Precision statements were determined using UOP Method 999, “Precision Statements in UOP Methods”. Repeatability and Site Precision A nested des
34、ign was carried out for determining heptane or toluene insolubles in four samples by two analysts. Each analyst carried out tests on two separate days, performing two tests each day for a total of 32 analyses. Using a stepwise analysis of variance procedure, the within-day and within-lab estimated s
35、tandard deviations (esd) were calculated for the components at the concentration levels listed 6 of 7 614-16 in Table 1. Two tests performed by the same analyst on the same day should not differ by more than the repeatability allowable differences shown in Table 1 with 95% confidence. Two tests perf
36、ormed in one laboratory by different analysts on different days should not differ by more than the site precision allowable differences shown in Table 1 with 95% confidence. Table 1 Repeatability and Site Precision, Insolubles, mass-% Repeatability Site Precision Sample Mean Within Day esd Allowable
37、 Difference Within Lab esd Allowable Difference “A“ Heptane Insolubles 11.5 0.36 1.4 0.42 2.6 “B“ Heptane Insolubles 0.46 0.019 0.07 0.023 0.09 “C“ Toluene Insolubles 2.69 0.077 0.30 0.102 0.40 “D“ Toluene Insolubles 22.0 0.12 0.5 0.15 0.6 The data in Table 1 are a short-term estimate of repeatabili
38、ty. When the test is run routinely, a control standard and chart should be used to develop a better estimate of the long-term repeatability. Reproducibility There is insufficient data to calculate the reproducibility of the test at this time. Time for Analysis The elapsed time for a single analysis
39、is 3.5 hours. The labor requirement is 1 hour. Suggested Suppliers Burdick and Jackson, 1953 S. Harvey Street, Muskegon, Ml 49442, USA, 1-800-322-2766, www.labchemicals- Fisher Scientific, 711 Forbes Ave., Pittsburgh, PA 15219-4785, USA, 1-412-490-8300, Millipore Corp., Prescott Road, Jaffrey, NH 0
40、3452 USA, 1-603-532-8711, VWR International, 1310 Goshen Parkway, West Chester, PA 19380, USA, 1-610-431-1700, 7 of 7 614-16 Figure 1 Insolubles Apparatus Set up of apparatus for Insolubles determination. (1) Reflux apparatus and Electromantle, (2) Filtration unit, (3) Solvent heating apparatus. 1 2 3
