ASTM D4085-93(R2021) pdf free download

ASTM D4085-93(R2021) pdf free download.Standard Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry
1. Scope
1.1 This test method covers the determination of the iron, copper, manganese, and calcium content ofcellulose pulp from wood or cotton. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Summary of Test Method
3.1 The sample is ashed in accordance with Test Methods D3516. 3.2 This test method is dependent on the fact that metallic elements in the ground state will absorb light of the same wavelength they emit when excited. When radiation from a given excited element is passed through a flame containing ground-state atoms of that element, the intensity of the trans- mitted radiation will decrease in proportion to the amount of the ground-state element in the flame. A hollow cathode lamp whose cathode is made of the element to be determined provides the radiation. The metal atoms to be measured are placed in the beam of radiation by aspirating the specimen into an oxidant-fuel flame. A monochromator isolates the charac- teristic radiation from the hollow cathode lamp and a photo- sensitive device measures the attenuated transmitted radiation.
4. Significance and Use
4.1 Manganese in pulp acts as a catalyst in oxidizing cellulose. 4.2 Iron in pulp can cause yellowness in rayon fibers and influence cellulose acetate plastics color. Iron also causes problems in photographic and blueprint papers. 4.3 Copper in pulp can act as a retardant in oxidizing cellulose and can affect viscose ripening. Copper interferes with the dye level of rayon fibers and influences cellulose acetate plastics color. 4.4 Calcium in pulps can cause problems in processing into acetate, rayon, cellophane, etc. Calcium can create undesirable deposits in viscose spinning and film casting operation. Cal- cium can influence viscosity control during cellulose acetate manufacture.
5. Apparatus
5.1 Atomic Absorption Spectrophotometer, consisting of an atomizer and burner, suitable pressure-regulating devices ca- pable of maintaining constant oxidant and fuel pressure for the duration ofthe test, a hollow cathode lamp for each metal to be tested, an optical system capable ofisolating the desired line of radiation, an adjustable slit, a photomultiplier tube or other photosensitive device, and a read-out mechanism for indicating the amount of absorbed radiation. 5.2 Oxidant—Air, which has been cleaned and dried through a suitable filter to remove oil, water, and other foreign substances, is the usual oxidant. 5.3 Fuel—Acetylene, commercially available, is the usual fuel. Acetone, always present in acetylene cylinders, can be prevented from entering and damaging the burner head by replacing a cylinder that has a gage pressure of only 3.5 kPa (50 psi) remaining. 5.4 Volumetric Flasks, 25-mL, 100-mL, and 1000-mL. N OTE 1—In listing the apparatus for this method, the items required for the ashing step are not listed. For these items refer to Test Methods D3516.
6. Reagents
6.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents shall conform to the specifications of the commit- tee on Analytical Reagents of the American Chemical Society, where such specifications are available. 6.2 Purity ofWater—Unless otherwise indicated, references to water should be understood to mean reagent water conform- ing to the requirements in Specification D1193, Type I. 6.3 Hydrochloric Acid (1 + 1)—Add 50 mL of concentrated hydrochloric acid (HCl, sp gr 1.19) to 50 mL of water. 6.4 Hydrochloric Acid (1 + 99)—Dilute 10 mL of concen- trated hydrochloric acid (HCl, sp gr 1.19) to 1000 mL with water. 6.5 Nitric Acid (1 + 1)—Add 50 mL of concentrated nitric acid (HNO 3 , sp gr 1.42) to 50 mL of water. 6.6 Sulfuric Acid (1 + 1)—Add 50 mL of concentrated sulfuric acid (H 2 SO 4 , sp gr 1.84) to 50 mL of water. 6.7 Standard Solutions—Dilute the solutions that follow with HCl (1 + 99) to prepare the standards to be used for calibration. Store all solutions in polyethylene bottles.