Ca(OH)2对煤炭腐植酸热解的影响

采用DTG、XRD及SEM技术，研究了干法混合与湿法混合下Ca(OH)₂对煤炭腐植酸热解的影响.结果表明：热分解温度低于400 °C时，无论干法和湿法，Ca(OH)₂对腐植酸脱吸附水和丢失官能团影响很小；440～610 °C时，湿法对应的腐植酸混合物热解失重速率高于干法；738 °C时，湿法中的腐植酸芳核结构热解失重速率达到最大值0.215 8 mg/min；Ca(OH)₂在腐植酸热解中起到消除002衍射峰，吸收CO₂及催化作用；Ca(OH)₂与腐植酸的混合物经H₂O浸泡后，Ca₂+可均匀负载在腐植酸分子表面发生络合反应，提高了催化热解效果.

Effects of Ca(OH)_2 on the Thermal Decomposition of Coal Humic Acid under Conditions of Dry and Wet Mixing

The effects of Ca(OH)2 on the thermal decomposition of coal humic acid under conditions of dry mixing and wet mixing were studied by means of DTG（derivative thermogravimetry），XRD（X ray diffraction）and SEM（scanning electron microscopy）. The results show that Ca(OH)2 additive has slight effect on the evaporation of the adsorbed water and the decomposition of the function groups from humic acid below 400 °C，whether under condition of dry mixing（i.e.,without the soaking role of H2O）or of wet mixing（i.e.,with the soaking role of H2O）. The mixture of humic acid and Ca(OH)2 under condition of wet mixing，440 °C～610 °C，presents higher weight loss rate than the mixture under condition of dry mixing. When heated up to 738 °C，the maximum weight loss rate of the aromatic nucleus from the humic acid mixture with the role of H2O arrives at 0.215 8 mg/min. It is found that Ca(OH)2 plays the role of the removal of 002 diffraction peak，the CO2 absorption and the catalysis in thermal decomposition of humic acid. What’s more，for the soaking role of H2O，Ca2+ ion is easily and uniformly loaded onto the molecule of humic acid，which is prone to complex reaction. As a result，the catalyse and the thermal decomposition of humic acid are enhanced.