关键词: 凹凸棒石;水洗除杂;酸改性;白度;化学组成

Abstract: In order to develop low grade palygorskite as welding electrode coated materials , the rinse and acid activation process of low grade palygorskite from Jiangsu were study systematically according to the requirements of welding electrode coated on whiteness and main oxides content .The suitable rinse and acid activation conditions were obtained . The experimental results show that , the whiteness of palygorskite improved by 17 .2％ under the optimum rinsing condition . After acid activation , the whiteness value of palygorskite is 72.1, and major oxides such as Al2O3, Fe2O3, MgO, CaO, was reduced by 28.5％, 39.8％, 50.7％and 98.3％, respectively.Infrared (FT-IR), X-ray fluorescence spectrum analysis ( XRD ) , X-ray fluorescence diffraction ( XRF ) and scanning electron microscope ( SEM) were used to characterize the composition , structure and appearance of the modified palygorskite .

Key words: palygorskite;rinse activation;acid modification;whiteness;chemical constitution