GB/T 9104.3-1988 Test method for industrial stearic acid Determination of acid value GB/T9104.3-1988 standard download decompression password: www.bzxz.net
Some standard content:
National Standard of the People's Republic of China Test methods for industrial stearic acids---Determination of acid value 1 Subject content and scope of application This standard specifies the determination method of industrial stearic acid. UDCbzxz.net 668.1.012 :543.06 GB 9104.3--88 This standard is applicable to the determination of industrial stearic acid produced by pressing or distillation after hydrolysis of animal and vegetable fats. 2 Definition Acid value: milligrams of potassium hydroxide consumed to neutralize 1g of sample. 3 Reagents 3.1 Potassium hydroxide (GB2306) 0.2 mol/L standard solution 3.2 95% ethanol (GB679) analytical grade 3.3 Phenolic acid indicator 1% ethanol solution 4 Apparatus 4.1 Burette 50 mL 4.2 Erlenmeyer flask 150 mL 5 Test procedure Weigh about 1 g of sample (accurate to 0.0001 g) and place it in an Erlenmeyer flask. Add about 70 mL of ethanol (3.2) (using phenolic acid as an indicator, neutralized with potassium hydroxide solution to a slightly reddish color) and heat to dissolve it. Then add 6 to 10 drops of phenolic acid indicator (3.3) and immediately titrate with potassium hydroxide standard solution (3.1) until it turns slightly red. The end point is that the color can be maintained for 30 seconds without fading. 6 Calculation of results AV= VxcX 56. 1 Wherein: A·V—acid value, mg/g; V—-volume of potassium hydroxide standard solution consumed during titration, mL, C—concentration of potassium hydroxide standard solution, mol/Lm-—mass of sample, g. Approved by the Ministry of Light Industry of the People's Republic of China on April 30, 1988 and implemented on October 1, 1988 The allowable error of parallel test results is 0.5. Additional remarks: GB9104.3—88 This standard was proposed by the Ministry of Light Industry of the People's Republic of China. This standard is technically managed by the Daily Chemical Industry Science Research Institute of the Ministry of Light Industry. This standard was drafted by the Daily Chemical Industry Science Research Institute of the Ministry of Light Industry. This standard is equivalent to the determination of acid value in the Japanese Industrial Standard JISK3331 "Industrial Hardened Oil Fatty Acids". 106 Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.