微波辅助合成低水硼酸锌

Synthesis of low-hydrated zinc borate assisted by microwave

采用氧化锌、硼酸为原料，利用微波加热合成低水硼酸锌（ZB-2335），以缩短反应时间、提高反应效率。实验中考察了反应温度、微波辐射时间、原料比等因素的影响；确定了适宜的反应条件为：反应温度105—110℃，微波辐射时间55min，氧化锌与硼酸的物质的量比1：11，氧化锌与水的物质的量比1：140，产率达97．6％。产品的组成分析结果符合要求，其失水温度高于340℃。微波加热条件下的反应速率约是常规加热法反应速率的13倍，该方法具有不引入外来离子，产物单一，不需精制、分离，反应母液可以重复利用，反应过程容易控制等特点，是合成阻燃剂ZB-2335的较佳路线。

The synthesizing method of low- hydrated zinc borate （ZB -2335 ） with boric acid and zinc oxide through microwave heating was studied, so as to shorten the reaction time and increase the reaction efficiency. Effects of reaction factors were investigated in the tests, such as reaction temperature, microwave irradiation time and ratio of raw materials etc.. The optimum conditions were confirmed as：reaction temperature 105 - 110 ℃, the time of microwave irradiation 55 min,the amount- of- substance ratio of zinc oxide and boric acid 1：11 ,the amount- of- substance ratio of zinc oxide and water 1 ： 140,the yield rate 97.6%. The composition analysis of product was up to the standard,and its dehydration temperature was higher than 340 ℃. The reaction was 13 times faster under microwave irradiation than under conventional heating. The method adopted in the study is a better approach to synthesize fire -retardant （ ZB -2335 ） ,which has a great deal of advantages, such as it may help single production without importing exotic ion, there is no need to refine or separate, mother liquor can be recycled and it＇s much easier to control in the reaction process etc..