Synthesis of Potassium Aluminum Sulfate ..
Chemistry Lab - Synthesis of Alum - YouTube
1) Simultaneously, the average pH of book papersshifted from 6.7 to 4.8. Barrett,in his X-ray fluorescence analysis of book papers from 1500 to 1800,found that papers in good condition contained less aluminum,potassium and sulfur than those in poor condition. Twentieth-century sizing trends can befurther exemplified by the postwar US rosin consumption, whichsteeply increased during the late 1950s. At the same time, up to 500,000 tons ofalum were used each year worldwide by the paper industry, whichamounted to 60% of the worldwide alum production.
Jul 19, 2015 · Synthesis of Alum - Duration: ..
Theywere ranked according to grading systems and could be purchased insolid pieces as so-called "patent alum." Well-known varietiesincluded cake alum, porousalum and Turkey Red Alum. Because of its greater concentration ofalumina (Al2O3) and cheaper productionprocedures, aluminum sulfate saved mill expenses and thereforereplaced aluminum potassium sulfate for most purposes in papermakingand particularly in rosin sizing towards the mid-19th century.
Synthesis of Chrome Alum - The Amateur Chemist
Slate and shale were other minerals which yielded alum whensubjected to several production steps which can be summarized asfollows: the aluminous rocks were piled up, roasted, andsubsequently extracted in water; potassium hydroxide was added tothe resulting solution; the crude alum crystals which formed in theevaporating solution were rinsed and redissolved in boiling water topurify the alum; the solution was transferred to large wooden caskswhere the alum crystals formed on the inside walls; and finally thecasks were dismantled and the crystals removed.Alum could be contaminated with byproducts of its manufacture,iron oxides and iron sulfates.