| There is a serious shortage of available soil in China,especially the shortage of urban planning land.It is necessary to treat and reuse the contaminated land.Thus,it is of unusual practical major to repair and treat the chemical contaminated sites that have been moved and shut down.In the announce published by Zhejiang Province in March 2015,the "specific rules for soil pollution control in Zhejiang Province" focuses on the contaminated land to be developed for mercantile building,mercantile serve,public reach and public serve,and focuses on carrying out the treatment scheme and effectively repairing the contaminated land.In this paper,Qiantangjiang silt is used as parent soil,cetyltrimethy lammonium bromide(CTMAB)modified calcium bentonite is used as organic modified bentonite.China has rich reserves of calcium bentonite,so the preparation of soil organic modified bentonite bentonite isolation wall material can be used as a new effective isolation wall adsorption material for adsorption,anti-seepage and anti pollution,which able significantly raise the quality of calcification bentonite physics and chemical nature of bentonite.With the mature technology and simple construction of sodium bentonite,it has been widely used and the preparation cost has been reduced.Moreover,bentonite itself is a kind of soil,consolidation and permeability characteristics of isolation wall materials,was develop to drew absorb isotherm and absorb kinetics,and the absorb mechanism were find the results display that the nature of the soil bentonite barricade wall is great improved by adding an organic improve bentonite,that has practical great for the promote to a higher office and sorption partition wall material.In order to understand and make full use of the properties of organic modified bentonite,cetyltrimethy lammonium bromide was used as the organic modifier material of bentonite.The adsorption of phenol on Bentonite mixed with cetyltrimethy lammonium bromide was systematically analyzed.The influence of modified dosages,organics modified bentonite dosage,generation rates time and solution p H on absorb of phenol was studied through round experiments,the absorb kinetics fitting bight and absorb isotherm were drew through the study of phenol absorb on soil organic modified bentonite bentonite partition wall materials.The induration permeability characteristics of cut wall materials was tested to explore the effect of organic modified bentonite substance on the compression,consolidation and permeability characteristics of partition wall materials.(1)The bodily properties in natural bentonite,for example swelling ability bentonite value,blue absorption capacity,colloid value and ion exchange capacity,have been effectively improved and the performance is better after being purified by sodium chloride.Therefore,sodium bentonite is selected for the preparation and practical application of bentonite based adsorption materials.Through the orthogonal test,the polymer content in the modified bentonite was taken as the evaluation index,and the best preparation factor were obtained as go after: CTMAB potency was 25.0 g / L,repercussion time was 90 min,water-marie shaking temperature was 60℃,p H value was 8.0.Among the four factors influencing the preparation of organic modified bentonite,the range of CTMAB concentration is far greater than that of the other three factors,this is CTMAB concentration is the best important factor.(2)Through the comparison of three adsorption kinetic models,it is discover that the initial period of phenol absorb by the quasi first-order travel equation is consistent,still the deflect was great in the later balance gradation.The false second-order travel formula includes the all-out process of adsorption,such as the internal and external spread of particles,the inward and outside surface adsorb.It can show the full reaction process great well and authentic present the whole gradation mechanism of phenol on the adsorbent,with R2 of0.9956.By equilibrium Langmuir and Freundlich adsorb isotherms,it is that the Langmuir adsorption tour equation had a grand limit of fitting,QM was 423.9mg/g,and the adsorption capacity of organically modified bentonite for phenol treatment was larger.(3)The addition of matter modified bentonite be capable of effectively heighten the adsorption rate,and the adsorption rate is more than 45%,which indicates that the addition of organic modified bentonite has a strong impact on the adsorption of phenol.When the mass concentration of adsorption is 50mg/L phenol solution 30 ml,the optimal dosage is 5%organic modified bentonite bentonite separation wall material,and the adsorption rate is 67%.(4)Adding a small amount of organic modified bentonite in the soil sample has little effect on the original solid characteristics of the soil prototype.With the raise by stable pressure,the finally clarify and stable ratio of the soil prototype raise.and that permeability coefficient of soil sample is lower under high pressure,which indicates that the incorporation of organic modified bentonite will retard the drainage consolidation of soil sample.After adding different amounts of organic modified bentonite,the soil samples show different consolidation characteristics.with content of organic better bentonite is 3%,the final cut down of the sample attain the maximum value of 5.62 mm,and the last invalid ratio attain the minimum value of 0.803. |
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