Catalytic Oxidation Of Glucose Towards Sodium Gluconate

Gluconic acid and its ramifications, like gluconates and glucose lactone, are the important and multifunctional organic chemicals. They are used broadly in chem.-engineering, food, pharmaceutical industry, and so on. The methods to prepare gluconic acid includes enzymatic oxidation, catalytic oxidation, compared with the former, the catalytic oxidation has such properties, simple production process, lower cost, and fast reaction rate, thus it is considered to be the most promoted method. However, the mono-metal catalysts are easy to be deactivated, leading to lower efficiency. Therefore, this paper uses bimetal catalysts to research the effect of preparation process on catalytic performance, and explore the ways to promote the stability of catalysts and products selectivity. Meanwhile, to optimize the preparation process can obtain the optimal parameter. The several new discovers during the experiment will be studied broadly and in depth. The results in this paper are summarized as follows:1. Using the single metal catalyst Pd/C, the conversion of the glucose is low (<40 %), and the selectivity of the sodium gluconate is moderate (<85 %). It indicates that single metal catalyst has a good performance for the side reaction.2. Bimetallic catalysts are used to increase the conversion of glucose and the selectivity of target product. The addition of the promoters rechange the Pd'electronic state, and promote the catalytic performance, and the space time yield of the sodium gluconate is similar to the value reported.3. The several factors during the catalysts preparation are studied, in order to optimize the preparation conditions and find the catalysts with the best performance. Pd-Mo catalyst shows skyscraping selectivity (>95 %) and moderate activity (>60 %); Pd-Cu shows better activity (>64 %) and the selectivity is higher than 90 %.4. Two novel methods are used in the experiment. One is that preparing the carbon material by myself which has a concave surface and without pore inside. The metal can only be supported on its surface outside. So its catalytic performance can be easily studied. The second is that two-step reduction, after the treatment, nanometer rate metals are highly dispersed in the surface of the activated carbon and Pd-Mo catalyst has a better improvement in its performance.