プラスチック容器の清浄法
スポンサーリンク
概要
- 論文の詳細を見る
Cleaning method for the containers which contained inorganic particles was investigated by rigorous chemical leaching. The important condition for removing the particles from plastics is that the leaching solution diffuses into the plastics and it reacts with the particles. <BR>About 0.1 percent of nitric acid and about 0.02 0.03 percent of hydrochloric acid were absorbed in Teflon but water was scarcely absorbed in it. However, after dealing by nitric acid leaching, the absorption of hydrochloric acid and water in Teflon increased up to 0.05 percent. In the case of polyethylene, about 0.1 percent of hydrochloric acid and about 0.05 percent of water were absorbed but nitric acid reacted with it and decomposed it.<BR>Pieces of Teflon sample were placed in each leaching solution (1: nitric acid, 2 : hydrochloric acid, 3: three-to-one mixture of concentrated nitric acid and hydrochloric acid) under boiling, and after every an adequate period, the samples were taken out and the change of the particles was observed under a microscope. This experiment showed that nitric acid was more active to the particles than hydrochloric acid. The degree of the dissolution of the particles by the leaching solutions decreased in an order, nitric acid, mixture of nitric acid, hydrochloric acid and hydrochloric acid. Some of the particles were not dissolved by any acids. However, the quantity of such particles was rather small, especially by the dissolution with the mixture of nitric acid and hydrochloric acid.<BR>The dissolution of particles can be divided into three steps, the first is the diffusion (introduction) step, where the solution reaches the particles, the second is the reaction step, where the crack between particles and plastic is occupied by the dissolved solution, and the final is the growth of branch pattern step where the dissolved solution diffuses into plastic and a branch pattern grows slowly and steady. A leaching period up to five days was necessary in order to remove large particles (200 microns). The recommended procedure is as follows.<BR>Teflon bottles, washed by water are immersed in a three-to-one mixture of concentrated nitric acid and hydrochloric acid for two days and then immersed in concentrated nitric acid for three days. (The presence of hydrochloric acid may be favorable in order to dissolve some metal oxide particles.) The leached Teflon bottles are then immersed in boiling water for three days (the water is changed every day) and are finally dried under vacuum.
- 社団法人 日本分析化学会の論文
著者
関連論文
- ガラスファイバの通信への応用
- 抽出吸光光度法による金属ウラン中の微量塩素の定量
- 銅中の微量水銀の吸光光度定量
- 溶媒抽出薄膜法による微量元素のけい光X線分析
- ジエチルジチオカルバミン酸によるビスマス,銅およびテルルの吸光光度定量法
- ジエチルジチオカルバミン酸錯塩の酸およびアルカリによる逆抽出
- ジエチルジチオカルバミン酸によるバスマス中の銅の定量
- 溶媒抽出-原子吸光法による銅,ニッケル,アルミニウムおよびウラン地金中の極微量カドミウムおよび亜鉛の定量
- 銅のスパーク法においてゼラチン使用による感度上昇法
- 原子吸光法によるアルミニウム地金およびアルミニウムウラン合金中の不純物の定量(ノート)
- アルミニウム地金中の微量ウランの光度定量
- プラスチック容器中の無機介在粒子
- プラスチック容器の清浄法
- 吸脱着還元を利用した金属中のイオウの吸光光度定量(ノート)
- 微量コバルト,銅およびニッケルの逐次吸光光度定量法
- EDTAをいんぺい剤とする非鉄金属中の微量鉄の吸光光度定量法
- 硫酸銅電解浴中のにかわの定量