【摘要】 灰渣经酸化处理制成多孔材料,可大幅降低其导热系数,在保温材料领域有很大的利用价值。文中采用醋酸和盐酸分别对灰渣进行酸处理,探究了酸浓度、反应温度和反应时间对改性灰渣导热系数的影响。利用原子吸收分光光度计(AAS)、X射线衍射分析(XRD)和比表面积分析仪(BET)对灰渣的组成和结构进行了表征,对引起导热系数变化的原因进行了分析。结果表明:盐酸和醋酸处理均可有效降低灰渣的导热系数,但醋酸效果更好。反应条件中酸浓度对导热系数的影响较反应时间和温度更大;而酸处理过程中一定的比表面积、介孔和结晶度的增加是导致其导热系数降低的主要原因。更多还原

【Abstract】 Gasification slag was used to produce a porous matter by simple acid treatment. This treatment also significantly decreased its thermal conductivity, and the treated porous slag had great potential to be utilized as an insulation material. In this study, the gasification slag was treated by acetic acid(HAc) and hydrochloric acid(HCl) to investigate the effect of acid concentration, reaction temperature and reaction time on the thermal conductivity of the modified slag. In addtion, its chemical composition and structure were characterized by the atomic absorption spectrometry(AAS), X-ray diffraction(XRD), nitrogen adsorption and desorption(BET/BJH), and some explanations were given to explain the thermal conductivity changes. The results show that both HAc and HCl play a key role in the decrease in thermal conductivity, but HAc is more effective. Moreover, the effect of acid concentration on thermal conductivity is greater than that of reaction time and temperature. While a certain specific surface area, the mesopores and the crystallinity contribute to the decrease in thermal conductivity.更多还原