Study on microscale chemical expenments for reduction of experiment wastes

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This project aimed at development of general purpose miniaturized chemical experiment apparatus system in order to reduce amounts of experiment wastes produced by chemical experiments. Most of the chemical experiments are planned to yield sufficient information, not to yield amount of product material. Therefore, as far as keeping the quality of information obtained from an experiment, amount of material used in the experiment can be reduced.In the first year of this project, downsizing of educational experiments adopted in the specialized course in the chemistry departments in a university. As a model experiment, the Friedel-Crafts acylation of toluene was adopted because this experiment includes several procedures applicable to general organic synthesis reaction, such as refluxing, liquid-liquid extraction, washing, drying, distillation and filtration. By using the smallest commercial apparatus, 1/6-scale experiment was examined. From the results of this examination the following points was understood : Production yield of object material was not degraded within a scale of 1/10 ; Handling easiness was not lost in such scale ; 1/10 was the practical limit of downsizing when commercial apparatus were used.In the second (final) year of this project, original apparatus were designed and manufactured in order to realize 1/25-scale downsizing. The model experiment adopted here was acetylation of glucose hydroxy-groups by acetic acid unhydrate, which is frequently executed in organic synthesis laboratories. This reaction includes dissolving, nitrogen purge, several-hour reaction in water bath, washing-extraction, drying and filtration.Production yield of 72% which is comparable to 76% in full-scale experiment was achieved by using newly designed apparatus, while amount of experiment wastes was reduced down to 1/25 of conventional experiment.