Fly ash-based porous pellets (FAP) were prepared using fly ash,palm kernel shells and bentonite.The FAP was later loaded with nano-zero valent iron (nZVI) using wet chemical reduction under atmospheric conditions with ascorbic acid as stabilizer.The removal rate of crystal violet (CV),scatter ratio and the weight of loaded iron were used to determine the best conditions for preparing FAP and FAPZVI.The adsorption behaviors of FAP and FAPZVI were investigated.The results showed that:(1) The optimum conditions for FAP preparation were:mass ratio of fly ash,bentonite and oil palm shell of 190∶ 95∶ 15,sintering temperature 800 ℃ and heating rate 10 ℃/min sintering time 30 min.(2) The optimum conditions of FAPZVI preparation were:iron/FAP mass ratio 1∶3 and shaking time 1 h;SEM analysis showed that the nZVI was loaded on the FAP successfully.(3) The removal rate of 200 mg/L CV using FAPZVI was up to 94.8％,while using FAP was only 26.2％ under the same conditions.FAPZVI removal mechanisms included physical adsorption by FAP and chemical reduction by nZVI as the dominant mechanisms.(4) FAP can keep the oxidation product of nZVI(Fe2+) in the surface,which can be reduced to nZVI again.Regeneration studies using 100 mg/L CV showed that after ten cycles,the removal rate was up to 97.6％ within 30 minutes.%为制备新型可再生吸附反应材料,以工业废弃物粉煤灰、棕榈壳等为主要原料,烧结制备FAP(粉煤灰基多孔材料),并以FAP为载体负载纳米零价铁,制备FAPZVI(粉煤灰基纳米零价铁多孔材料),以散失率、龙胆紫去除率、纳米零价铁负载量等为指标,确定FAP及FAPZVI的最佳制备条件,并考察二者对染料龙胆紫的去除特性.结果表明:①FAP的最佳制备条件为m(粉煤灰)∶m(膨润土)∶m(棕榈壳)=190∶95∶15.升温速率10℃/min.烧结温度800℃.保温时间30 min.②FAPZVI最佳制备条件为m(Fe)/m(FAP) 1∶3.振荡时间1h.选用抗坏血酸为稳定剂.过程中无需使用惰性气体;SEM结果表明纳米零价铁被成功负载于FAP上.③FAPZVI对200 mg/L龙胆紫的去除率为94.8％.FAP同条件下的去除率仅为26.2％.FAPZVI对龙胆紫的去除同时存在物理吸附和化学还原作用.并且纳米零价铁的还原占主导作用,④FAPZVI再生10次后30 min内对100 mg/L龙胆紫去除率高达97.6％.研究显示.FAP可将纳米零价铁氧化产物Fe2+固定在表面.经还原后可再生为纳米零价铁.具有良好的再生性能.
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