摘要
以胜利褐煤为研究对象,利用XRF、FT-IR等手段,采用灰分、pH值、不同相对蒸气压下的复吸水含量等参数,研究了Ca2+的离子效应对褐煤在不同相对蒸气压下复吸水含量的影响。研究结果表明,煤中Ca2+的负载量随用于交换的钙离子溶液浓度的增大而增加。煤中Ca2+的负载量对煤样的平衡复吸水含量影响较大,Ca2+负载量越大,煤样的平衡复吸水含量越大。相对蒸气压高于92%平衡复吸水含量的主要控制因素为游离水分子与游离水分子之间的相互作用力。相对蒸气压在11%~92%平衡复吸水含量的主要控制因素为金属水簇Ca+(H2O)n与毛细管之间的毛细管作用力。
Shengli lignite has been acid-washed.The chemical composition of ash from the raw sample was determined by X-ray Fluorescence（XRF）.The acid-w ashed lignite w as subsequently exchanged w ith different concentrations of Ca（CH 2 COOH） 2 solution.Ion-exchange process w as characterized by FT-IR,the ash content and pH value.The re-adsorption w ater contents of treated and raw samples w ere determined across a range of relative vapor pressures.The extend of ion-exchange reaction betw een Ca（CH 3 COO） 2 and-COOH groups w as controlled by the concentration of Ca（CH 2 COOH） 2 solution.The effects of Ca2＋on equilibrium re-adsorption w ater values varied depending on relative vapor pressures and the amount of loaded Ca2＋.Furthermore,the factor that controls equilibrium re-adsorption w ater content at relative vapor pressure of 92% or less is capillary force betw een Ca2＋-carboxyl group complex and capillary.How ever,at higher relative vapor pressure the key factor becomes interactions of free w ater molecules.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2013年第9期1025-1029,共5页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(51274197)
国家重点基础研究发展规划(973计划
2012CB214900)
关键词
离子交换
相对蒸气压
平衡复吸水含量
ion-exchange
relative vapor pressure
equilibrium re-adsorption water content
