碳水化合物之氧化反應　第一報　氧化蔗糖製造草酸

Oxidation of Carbohydrates I. Oxalic Acid from Sucrose by Oxidation

陸貫一(Kuan-I Lu) ； 羅仁道(Ren-Daw Luo)

《化學》 55年2期 (1966/06) Pp. 76-84

https://doi.org/10.6623/chem.1966012

摘要

蔗糖用適當觸媒，行銷酸氧化，可產生草酸(oxalic acid)。此法所得的草酸純度很高，可供作純粹化學試藥，勝過其他工業生產的蟻酸鈉加熱法、木屑燒碱法等。觸媒以釩酸鈉(sodium meta-vanadate)最佳。實際產率，合理論量的70%，此與文獻上所載最高產率相符合。硝酸用量較多，產生1 Kg草酸約需費100%硝酸1.6~1.8kg，但反應所生之NO_2經耗費硝酸0.64~0.72kg，如導入氧氣則回收率可高達80%以上，僅耗費硝酸0.32~0.36kg。吸收塔如加改良，則硝酸回收率可再提高，故需用硝酸量尚可相對減少。關於反應溫度、反應時間、觸媒量、酸量等相互關係均予研討。

並列摘要

Sucrose can be oxidized in to oxalic acid with nitric acid in the presence of proper catalyst. The purity of the product is very high and can be used as c.p, grade reagent. It excels those industrial products either from the sodium formate process or from the alkali-sawdust process. Sodium meta-vanadate was proved to be the most effective catalyst. The average yield is 70% of the theoretical conversion, which is about the same as reported in the literature.Consumption of nitric acid is rather high; for producing 1 kg of oxalic acid 1.6-1.8 kg of 100% HNO_3 is required. Nevertheless, the NO_2 gas evolved can be absorbed with water or mother liquor and converted back to HNO_3 with air, giving about 60% recovery, whereas with oxygen, giving recovery more than 80%. With this refinement in operation, 1 kg oxalic acid consumes only 0.64-0.72 kg HNO_3 in the former case or 0.32-0.36 kg HNO_3 in the latter case. In order to recover more NO_2 and to lower the production cost, the recovery operation can be much improved by changing the details of gas absorbing system. The relationships between the reaction temperature, the reaction time, the catalyst concentration, and the amount of nitric acid are given.