Experimental report on the preparation of adipic acid

Preparation Experiment Report of Adipic Acid
Overview of Preparation Experiment Report of Adipic Acid: Adipic acid, also known as dimethyl adipate, is an important chemical raw material widely used in polyester resins, coatings, plastics, dyes and other fields. The aim of this experiment is to prepare adipic acid through the acid catalyzed reaction of ammonium bicarbonate and hexanediol. Experimental steps: 1 Preparation before experiment:
- Prepare the required reagents: ammonium bicarbonate, hexanediol, sulfuric acid, calcium chloride. -Preparation solution: Dissolve 50 ml of hexanediol and 10 g of ammonium bicarbonate in a 250 ml three necked flask. two Reaction process: Heating reaction: Connect a three necked flask to a condenser tube and a dropper funnel, heat the reaction mixture to boiling, and maintain the reaction temperature at 140-150 degrees Celsius. -Auxiliary drying: During the reaction process, sulfuric acid is slowly added through a dropping funnel to maintain the acidity of the reaction solution. At the same time, moisture is removed through a calcium chloride drying tube to promote the reaction. three Reaction completion: - Reaction time: The reaction continues for 2-3 hours until the reaction solution becomes transparent. -Cooling and Separation: After stopping heating, let the reaction flask cool to room temperature. Then, transfer the reaction solution to a funnel and extract it with an equal volume of ether solvent. -Distillation purification: Transfer the organic phase to a distillation flask for distillation purification, and collect the target product. Experimental data and results: Through the above experimental steps, we successfully prepared adipic acid. During the experiment, we observed that at the beginning of the reaction, the reaction solution appeared as a milky white suspension, and as the reaction progressed, the liquid gradually became transparent. After the reaction, we obtained colorless and transparent adipic acid product. Experimental discussion: In this experiment, ammonium bicarbonate and hexanediol were used as reactants to prepare adipic acid through acid catalyzed reaction. Ammonium bicarbonate decomposes during heating to produce ammonia and carbon dioxide, while hexanediol reacts with ammonia to produce adipic acid. By adding appropriate amounts of sulfuric acid and calcium chloride, the reaction can be promoted and water can be removed, resulting in improved yield and purity. The control of reaction temperature is crucial in experiments. Excessive temperature may lead to product decomposition or side reactions, reducing yield and purity. Therefore, during the heating reaction process, it is necessary to closely control the reaction temperature within the range of 140-150 degrees Celsius. In addition, the acidity or alkalinity of the reaction solution can also affect the progress of the reaction. Slowly adding sulfuric acid through a dropper funnel can maintain the acidity of the reaction solution and promote the formation of adipic acid. Meanwhile, removing moisture through calcium chloride drying tubes can reduce the interference of moisture on the reaction. Summary: Through this experiment, we successfully prepared adipic acid and observed the entire reaction process. The experimental results indicate that the method of preparing adipic acid by reacting ammonium bicarbonate with hexanediol is feasible. By controlling the reaction temperature and acidity of the reaction solution reasonably, the yield and purity can be improved. The preparation method of adipic acid is of great significance for research and application in related fields.