超声作用下碳酸钙晶体的形态变化

为了解超声场对碳酸钙晶体形态的影响,揭示其作用机制,采用自行设计的超声设备(40 kHz,0.88W/cm2)来处理不同过饱和度的碳酸钙溶液,并比较有、无超声作用的碳酸钙晶体的形态和大小.研究结果表明:超声空化效应所产生的微观热量不仅能促进过饱和溶液中碳酸钙晶核的形成,迅速降低溶液的过饱和度,还能改变碳酸钙晶体的形态;经超声处理的碳酸钙过饱和溶液中形成了大量微小的碳酸钙晶体,其中绝大部分为文石,少量为细小方解石,它们长时间悬浮在溶液中;超声的机械效应对碳酸钙晶体形态的影响甚微.

Morphology Variation of Calcium Carbonate Crystal Irradiated by Ultrasonic

In order to reveal the effects of ultrasonic irradiation on the morphology of calcium carbonate and the corresponding mechanism,calcium carbonate solutions with various degrees of supersaturation were treated using a self-devised ultrasonic equipment(40 kHz,0.88 W/cm2).The morphology and size of the calcium carbonate cry-stal with ultrasonic irradiation were then compared with those of the crystal without radiation.The results indicate that(1) the microcosmic energy generated by cavitation effect in the supersaturated solution accelerates the formation of crystal nuclei,decreases the supersaturation degree of solution and changes the morphology of the crystal,(2) a large number of calcium carbonate crystals exist in the form of aragonite while little in the form of calcite,and the crystals suspend in the solution for a long time,and (3) the mechanical effect of ultrasonic has little effect on the morphology of calcium carbonate crystal.