Extraction of caffeine from tea except ethanol extraction

In the experiment of extracting caffeine from tea, in addition to ethanol extraction, what solvents can be used
Ethyl acetate, chloroform, pyrimidine, pyrrole, tetrahydrofuran and acetone can also be used. Each gram of caffeine is soluble in 46 ml of water, 5.5 ml of hot water (80 ℃), 1.5 ml of boiling water, 66 ml of ethanol, 22 ml of hot ethanol (60 ℃), 50 ml of acetone, 5.5 ml of chloroform, 530 ml of ether and 100 ml of benzeneExperimental report on extracting caffeine from tea
Teaching requirements for extracting caffeine from tea: learn the basic principles and methods of extracting caffeine from tea, and understand the general properties of caffeine. Master the principle and method of extracting organic matter with Soxhlet extractor. Be more familiar with the basic operations of extraction, distillation and sublimation. Preview content: extraction
How to purify caffeine
Purifying caffeine is a high school course. In chemistry class, there was an experiment to extract caffeine from tea. Experiment report on extracting caffeine from tea objective to learn the method of extracting alkaloids and the principle of Soxhlet extractorHow to extract caffeine from tea
The traditional methods of extracting caffeine from tea include ethanol reflux method and sodium carbonate solution boiling method. However, the former needs to be refluxed in Soxhlet extractor for more than 215h, which has a long cycle, high alcohol consumption and energy consumption, and is not conducive to industrial productionHow to extract caffeine from tea
A large amount of sublimation at 180 ℃ and needle like crystallization after cooling. This property is used for extraction. At present, domestic colleges and universities mostly use the sublimation method [1-2] for teaching, Control the temperature at 182 ~ 185 ℃, sublimate for 15 min, and obtain 5 ~ 6 mm long crystals after cooling. The crystals are white needlesHow to extract caffeine from tea
The experimental raw materials for extracting caffeine from tea by microwave radiation are oolong tea and black tea. The main reagents are edible alcohol (98%) and quicklime (c.p.). The main instruments are nn-k577wfs microwave oven and xt4-100x micro melting point testerWhy use Soxhlet extractor to extract caffeine from tea? Why not use ordinary reflux condensing device
Because caffeine begins to sublimate at 100 ℃, it takes a long time to heat it with a general reflux condensing device, and caffeine sublimates and escapes from the solution, and ultimately cannot be obtained. While Soxhlet extractor uses condensed ethanol to extract, the sublimation of caffeine is greatly reduced. Although in the absence of Soxhlet extractors, reflux condensing devices can be used. HoweverHow does tea extract caffeine
Extraction of caffeine (1) extract 8g tea, put it into the filter paper cylinder of Soxhlet extractor, add 80ml of 95% medical alcohol and several pieces of zeolite into the flask of extractor, install Soxhlet extractor, connect condensate, heat it, and extract continuously for 1 ~ 1.5 hours (extraction can be stopped when the color of extract is very light)The process of extracting caffeine from tea (simpler)
Add a small amount of ethanol from its top until it just goes down (2) Heat with water bath. After continuous extraction for 2~3h, stop heating immediately when the extract becomes very weak and the liquid in the extractor has just been sucked down (3) After cooling, transfer the extract to a 250ml conical flask to obtain crude caffeine, and stick a label for further purificationHow to extract caffeine from tea or coffee beans??? Detailed explanation
Objective: to learn the basic principles and methods of extracting caffeine from tea and understand the general properties of caffeine; Master the principle and method of extracting organic matter with Soxhlet extractor; Be further familiar with the basic operating experimental equipment such as extraction, distillation and Sublimation: tea and 95% ethanol