Preparation Of Composite Ceramsite And Their Adsorption Phosphate Properties

Due to its low cost, stable structure, simple operation, recyclability and high adsorption for contaminant, ceramsite have been paid lots of attention in sewage treatment in recent years. Based on the advances in application of ceramsite to the treatment of sewage containing phosphate were reviewed in this paper. Solid waste was used as the main raw meterials, mixing with other meterials to produce ceramsite, and this novel ceramsite were applied for phosphate removal from aqueous solution.Some important parameters in the manufacturing process, which greatly affect the characteristics of ceramsite by several anslysis methods. The adsorption mechanisms was also discussed. The main detailed contents of the research include the following aspects:1) Phosphate removal by using Magnesium Oxide/ Construction Waste of subway composite ceramsite: Using solid waste residue of subway construction as the main raw material, mixing with magnesium oxide, a novel composite ceramisite was prepared. Sintering temperature, contents of magnesium oxide, effects of adsorption p H, temperature and time of attachment were investigated. The optimal preparation of the composite ceramsite obtained at 300? after preheating 25 min and then 20 min of sintered at 700?, which the content of magnesium oxide was 20%. Sorption capacity increased with increasing the sorption temperature, and the maximum sorption capacity can reach at 3811.6mg/kg when the initial temperature was 80?.2) Preparation and mechanism of shield residues-corbon composite ceramsite ceramsite for phosphate adsorption from aqueous solution: Using solid waste residue of shield residues, powdered rice straw and magnesium oxide as starting materials to prepare composite ceramisite by lower temperature calcination. Paramaters, such as sintering temperature, ratio of materials, effects of adsorption p H, temperature of adsorption and time of attachment on phosphate adsorption were investigated. The optimal preparation of the composite ceramsite obtained sintering at 700?, which the perfect ratio was 7:2:1. The optimum of adsorption was p H 6.3, and reaches adsorption equilibrium status in 12 hours. The Lagergren pseudo-second-order kinetics were suitable for the process, and the Temkin isotherm model fits the date well.3) Preparation and mechanism of lanthanum(?) composite ceramsite for phosphorus adsorption from aqueous solution: Using solid waste residue of chopped corn stover, lanthanum carbonate, and palygorskite clay as starting materials to prepare composite ceramisite by lower temperature calcination. Paramaters Such as effects of adsorption p H, temperature and time of attachment on phosphate adsorption were investigated. The result shows that ceramsite has a large BET-SAA(75.26m2/g).Within the range of p H from 2.9 to 12.3, the maximum removal rate capacity can reach over 96%.To simulation the equilibrium phosphate date, the Freundlich equation was better than the Langmuir equation.In this dissertation, the optimum conditions of synthesis of ceramsite were studied and discussed.The different types and functions with ceramsite that were obtained through different raw materials have some innovation. It will broad the researching field of solid waste utilizationand and provide important theoretical basis for resource utilization.