Modification Of Oil Shale Ash On The Adsorption Of Lead And Cadmium

With the shortage of global petroleum and coal resource,oil shale as a kind of new altermative energy sources,is becoming more and more important. Oil shale resort was mainly applied to utilization of retorting and burning for electricity. There is much oil shale ash during the producing of the oil. Oil shale ash is discarded as waste unceremoniously so that it lead a serious impact on the global environment and a waste of resource. In addition, much stacking ash needs to occupy a lot of land and lead the environmental pollution. Therefore , the comprehensive use of oil shale ash had an important practiacal significance.Based on oil shale ash from Chengda company located in Huadian of Jinlin province,China.The adsorption characteristics of lead and cadmium from aqueous solutions by using modified oil shale ash were studied systematically.The main content is that oil shale ash such as the raw materials was converted into a new adsorbent by an alkali fusion and hydrothermal synthesis method. The alkali-treated oil shale ash was used as low cost adsorbent to remove of lead and cadmium from aqueous solutions.The chang of physical structure of the modified oil shale ash as the research object, was obtained by the testing method of SEM. The adsorption characteristics of lead and cadium on aquetion by modified oil shale ash were studied by a good deal of static adsorption experiments.Effects of all kinds of parameters such contact time in shaker, adsorbent dosages, particle size and pH of solutionson were investigated,the process of synthesis were discussed by the analysis of the adsorption kinetics. Adsorption thermodynamics and the key parameters were studied and optimized to reach the best experiment conditions.And effects of adsorption were proved by using Energy dispersive spectrometer (EDS) and Langmuir adsorption isotherm were put to use to fit the process of adsorption or not. The test results have shown that the modified oil shale ash was a promising and efficient adsorbent with a simple preparation, abundant raw materials and low cost.?After oil shale ash modified, the porosity increased and surface attached to the hydroxyl groups by SEM analysis, on the best condition that the pH was on nature and the temperature was room temperature, holding time in shake was 6 minutes, the particle size was 200 mesh, the adsorbent dasage was 0.4g and 1.0g respectively, the removal achieved at 97.21% and 96.07%. Modificated oil shale ash which have participated in the adsorption reaction contained lead and cadium elements as compared with unreacted ash by EDS. And the process of lead and cadium ions'adsorption was a non-spontaneous process,and the Langmuir model come up to the process of adsorption with? R2>0.996 in all cases. Based on such results, it is concluded that the alkali-treated oil shale ash may possess strong potentials used in wastewater treatment.