Study On Preparation Of Active Filter Material Based On Natural Zeolite And Manganese Removal Efficiency

Sand filtration manganese removal is a common manganese removal process.At this stage,the filter material in some manganese water removal plants in northern China needs to go through a long start-up stage after being put into the filter,resulting in the problem of seriously exceeding the manganese ions in the water plant in the early stage of operation.Directly produced outside the filter cell has a certain ability to remove manganese,low price,easy to obtain filter material,in the early stage of the operation of the water plant after the filter can effectively improve the effect of manganese removal,to achieve the water standard,has a wide range of research prospects and practical engineering significance.In this study,the preparation process of manganese oxide zeolite was optimized by orthogonal testing of manganese oxide zeolite by means of Mn SO₄alternating natural zeolite impregnated with oxidant,and the characterization and physicochemical properties of zeolite zeolite were analyzed by considering the influence of p H,oxidant concentration and oxidant type on the manganese oxide capacity The beaker experiment was used to explore the manganese removal efficiency of the prepared manganese oxide zeolite under different water quality conditions（ferrous ion concentration,p H,hardness）;the dynamic filtration experiment was carried out to explore the separate manganese removal effect and synchronous iron and manganese removal effect of manganese oxide zeolite,and the start time of the filter column under different filter speed conditions was studied.The final conclusion was reached:Zeolite adsorption type of Mn²⁺is a single-molecule layer that can spontaneously carry out surface activation energy uniformity,and also ion exchange,the adsorption performance of Mn2⁺is stronger than that of natural manganese sand and much larger than that of quartz sand,and the saturated adsorption amount is 0.5556mg/L.It is more suitable for the preparation of manganese active filter media as a matrix.Sodium hypochlorite has the strongest ability to convert divalent manganese into high-valent manganese oxides.The degree of influence of the three factors on the amount of manganese carried in the manganese carrier process is:the type of oxidant>the p H>the oxidant concentration.The optimal preparation conditions for manganese oxide zeolite are:at 20°C,101KPa,200 mg/L of manganese sulfate and 0.001 mol/L,p H=8 The sodium hypochlorite is alternately macerated12 times,of which the single prepared zeolite has a mass of 30 g.The formation of sodium-based zeolites by supporting a layer of loose and porous manganese oxides is conducive to the pore transport of Mn²⁺on the zeolite surface and the binding of zeolite particles to manganese oxides.Manganese oxides are mainly composed of Mn O₂and 3-valent manganese oxides,containing 6-valent manganese substances.The total amount of manganese active filter media not-on-load manganese based on natural zeolite was6.5398mg/g,the maximum manganese demanganization rate within 120h of shock culture was 0.97%,and the manganese oxide formed on the surface of the matrix was stronger and the loss of manganese oxide in the process of manganese removal was small.Manganese-carrying active zeolite has the function of simultaneous removal of iron and manganese,and the removal rate of manganese ions is higher when treating a single manganese-containing raw water.The removal effect is much higher than that of natural zeolite filter material,slightly lower than that of mature filter media in water plants,and the average manganese removal rate is 81.76%.When treating iron-manganese composite raw water,the average removal rate of Mn²⁺decreased by 8.89 percentage points.The factors affecting the removal rate of manganese ions are mainly ferrous ions,hardness and p H.The optimal water quality conditions suitable for manganese zeolite are:ferrous concentration of0.15mg/L,p H=7.73,hardness of 181.4mg/L;at this time,the removal rate of manganese ions reaches the highest value of 93.29%.Manganese zeolite running at a 1m/h filter speed was successfully started on the 8th day,but the start-up time was also extended as the filter speed increased,and the start-up time was greater than 15d when the filter speed was 4m/s。...