{"id":1702,"date":"2025-11-20T18:07:49","date_gmt":"2025-11-20T18:07:49","guid":{"rendered":"https:\/\/pharmacoguide.com\/?p=1702"},"modified":"2025-11-20T18:07:49","modified_gmt":"2025-11-20T18:07:49","slug":"determination-of-acetyl-value","status":"publish","type":"post","link":"https:\/\/pharmacoguide.com\/?p=1702","title":{"rendered":"Determination of Acetyl Value"},"content":{"rendered":"<h3 style=\"text-align: center;\"><span style=\"text-decoration: underline;\"><em><strong>Title:<\/strong> <\/em><strong><em>Determination of Acetyl Value<\/em> <\/strong><\/span><\/h3>\n<p>&nbsp;<\/p>\n<p>1.\u00a0\u00a0\u00a0\u00a0\u00a0 Objective: To determine the Acetyl Value of the sample.<\/p>\n<ol start=\"2\">\n<li><strong>Principle:<\/strong> The acetyl value is the number which expresses in milligrams the amount of Potassium Hydroxide required to neutralise the acetic acid liberated by the hydrolysis of 1 g of acetylated substance.<\/li>\n<\/ol>\n<p><strong>\u00a0<\/strong><\/p>\n<p><strong>3. Procedure:<\/strong><\/p>\n<p>Determine the saponification value of the substance being examined as per saponification value test.<\/p>\n<p>Acetylate the substance being examined by the following method:<\/p>\n<p>Place 10 g of sample with 20 ml of\u00a0Acetic anhydride\u00a0in a long-necked, round-bottomed 200-ml flask attached to a reflux air condenser. Support the flask on a sheet of heat-resistant material in which a hole of about 4 cm in diameter has been cut and heat it with a small, naked flame, not more than 25 mm in height and which does not impinge on the bottom of the flask. Boil gently for 2 hours, allow to cool, pour into 600 ml of\u00a0water\u00a0contained in a large beaker, add 0.2 g of\u00a0pumice powder\u00a0and boil for 30 minutes. Cool, transfer to a separator and discard the lower layer. Wash the acetylated product with three or more quantities, each of 50 ml, of a warmed saturated solution of\u00a0sodium chloride\u00a0until the washings are no longer acid to\u00a0litmus paper. Finally shake with 20 ml of warm\u00a0water\u00a0and remove the aqueous layer as completely as possible. Pour the acetylated substance into a small dish, add 1 g of powdered\u00a0anhydrous sodium sulphate, stir thoroughly and filter through a dry pleated filter. Determine the\u00a0saponification value\u00a0of the acetylated substance.<\/p>\n<p>&nbsp;<\/p>\n<p>Calculate the acetyl value from the expression:-<\/p>\n<p><strong>\u00a0\u00a0 \u00a0Acetyl value<\/strong> = \u00a0\u00a0<u>1335 (b \u2013 a )<\/u><\/p>\n<p>(1335 \u2013 a)<\/p>\n<p>&nbsp;<\/p>\n<p>Where, <strong>a<\/strong> = Saponification value of the substance;<\/p>\n<p><strong>b<\/strong> = Saponification value of the acetylated substance.<\/p>\n<p>&nbsp;<\/p>\n<hr \/>\n<p>&nbsp;<\/p>\n<h4 style=\"text-align: center;\" align=\"center\"><em><u><span style=\"font-size: 16.0pt; line-height: 115%;\">&#8220;End of Document&#8221;<\/span><\/u><\/em><\/h4>\n","protected":false},"excerpt":{"rendered":"<p>Title: Determination of Acetyl Value &nbsp; 1.\u00a0\u00a0\u00a0\u00a0\u00a0 Objective: To determine the Acetyl Value of the sample. Principle: The acetyl value is the number which expresses in milligrams the amount of Potassium Hydroxide required to neutralise the acetic acid liberated by the hydrolysis of 1 g of acetylated substance. \u00a0 3. Procedure: Determine the saponification value [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"templates\/template-full-width.php","format":"standard","meta":{"footnotes":""},"categories":[41],"tags":[],"class_list":["post-1702","post","type-post","status-publish","format-standard","hentry","category-elemental-impurities"],"_links":{"self":[{"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/posts\/1702","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1702"}],"version-history":[{"count":1,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/posts\/1702\/revisions"}],"predecessor-version":[{"id":1703,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=\/wp\/v2\/posts\/1702\/revisions\/1703"}],"wp:attachment":[{"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1702"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1702"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pharmacoguide.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1702"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}