硫酸钾结晶及动力学研究(英文)-豆柴文库

您所在位置：网站首页 / 硫酸钾结晶及动力学研究(英文).docx / 文档详情

在线预览结束，喜欢就下载吧，查找使用更方便

5 金币

下载文档

/ 2

下载提示

如果您无法下载资料，请参考说明：

1、部分资料下载需要金币，请确保您的账户上有足够的金币

2、已购买过的文档，再次下载不重复扣费

3、资料包下载后请先用软件解压，在使用对应软件打开

文本预览

硫酸钾结晶及动力学研究(英文)
PotassiumSulfateCrystallizationandKineticsStudy
Introduction
Potassiumsulfate(K2SO4),alsoknownassulfateofpotash,isawidelyusedsaltinvariousindustriessuchasfertilizers,pharmaceuticals,andfoodproduction.Itisawhitecrystallinesolidthatissolubleinwaterandhasahighthermalstability.TheproductionmethodofK2SO4usuallyinvolvesthereactionbetweenpotassiumchlorideandsulfuricacid.Thesolidproductisobtainedviaacrystallizationprocess.Thecrystalstructure,morphology,andsizehaveanimportantimpactonthephysicalandchemicalpropertiesofK2SO4.Therefore,theunderstandingofthecrystallizationkineticsandmechanismiscrucialfortheoptimizationoftheproductionprocessandproductquality.
CrystallizationProcessandKinetics
Crystallizationisaprocessinwhichdissolvedsolutesprecipitatefromasolutiontoformcrystallinesolids.Theprocesscanbedividedintotwostages:nucleationandgrowth.Thenucleationstageistheformationofsmallcrystalnucleifromsupersaturatedsolution.Thegrowthstageistheenlargementofthenucleibydepositionofsolutefromthesolutionontothesurfaceofthegrowingcrystal.Thekineticsofcrystallizationincludestheprocessesofmasstransferandreactionkinetics.Masstransferincludesthediffusionofsolutemoleculesfromthebulksolutiontothesurfaceofthecrystal.Reactionkineticsincludethechemicalreactionsthatoccurduringtheformationofthecrystalnucleiandthegrowthofthecrystal.
IntheproductionprocessofK2SO4,thecrystallizationcanbecarriedoutbyevaporatingthesolutionorcoolingthesolution.Thecoolingprocessisusuallypreferredduetothelowerenergyconsumptionandbettercontrolofcrystalsizeandmorphology.Thecrystalshapeandsizecanbecontrolledbytheselectionofthecrystallizationconditionssuchastemperature,pH,andstirringrate.ThemostcommonlyobservedcrystalshapesofK2SO4arevoid-structured,rectangular,andneedle-shaped.ThecrystalmorphologyaffectsthephysicalandchemicalpropertiesofK2SO4,suchasthesolubility,density,andangleofrepose.
ThenucleationrateandgrowthratearethekeyparametersinthecrystallizationkineticsofK2SO4.Thenucleationrateisaffectedbythesupersaturat