吸附--催化氧化技術(shù)處理廢水中苯酚的研究.pdf

1、楊洋：吸附催化氧化技術(shù)處理廢水中苯酚的研究摘要含酚廢水是一類(lèi)毒性高且難以生物降解的有機(jī)廢水，含酚廢水的處理方法一直是人們研究的重點(diǎn)。隨著環(huán)境保護(hù)要求的提高，廢水的達(dá)標(biāo)排放要求也越來(lái)越嚴(yán)格。因此，單一的處理方法往往難以滿(mǎn)足企業(yè)的需求，多種水處理技術(shù)的組合成為研究的熱點(diǎn)方向之一。本文采用吸附催化氧化組合技術(shù)對(duì)模擬廢水與石化廢水中的苯酚進(jìn)行深度處理，即先通過(guò)吸附的方法對(duì)預(yù)處理后廢水中的苯酚進(jìn)行富集，再將吸附的苯酚脫附下來(lái)進(jìn)行集中催化氧化處理，

2、從而大大降低生化處理的時(shí)間，提高廢水的處理效率?；钚蕴坷w維(ACF)作為一種新型的吸附材料，具有比表面積大、孔徑分布窄、微孔含量豐富、吸脫附速度快、再生條件溫和等優(yōu)點(diǎn)，可以作為一種有效的處理廢水的吸附劑。實(shí)驗(yàn)首先采用ACF為吸附劑，以苯酚水溶液作為模擬廢水，考察了不同條件對(duì)ACF吸附苯酚性能的影響，并且考察了NaOH溶液對(duì)苯酚的脫附效果。結(jié)果表明，ACF對(duì)苯酚的吸附速率較快，一般情況下吸附30min且N可接近平衡；溫度對(duì)ACF吸附的影響

3、較小，升高溫度不利于ACF吸附苯酚；增jJHACF投加量可提高苯酚的去除率，但平衡吸附量下降，ACF禾IJ用率降低；酸、中性介質(zhì)條件有利于ACF吸附苯酚。吸附飽和后的ACF選用質(zhì)量濃度3％的NaOH溶液在60。C下即可脫附再生，ACF經(jīng)10次吸附與脫附重復(fù)實(shí)驗(yàn)后，吸附性能穩(wěn)定。采用ACF為吸附劑，對(duì)比研究TACF對(duì)模擬廢水與石化廢水中苯酚的吸附過(guò)程，主要從吸附等溫線(xiàn)、吸附動(dòng)力學(xué)以及動(dòng)態(tài)吸附脫附等方面作了比較。采用LangmuirNFre

4、undlich兩種吸附模型對(duì)實(shí)驗(yàn)數(shù)據(jù)進(jìn)行擬合，結(jié)果表明ACF對(duì)模擬廢水中苯酚的吸附更符合Langmuir吸附模型，ACF對(duì)石化廢水中苯酚的吸附更符合Freundlich吸附模型，主要因?yàn)槭瘡U水中油類(lèi)等物質(zhì)的存在，影Ⅱ向至I]ACF表面對(duì)苯酚的吸附，不再是單純的單分子層吸附。動(dòng)力學(xué)實(shí)驗(yàn)表明，ACF吸附模擬廢水和石化廢水中苯酚時(shí)，平衡吸附量隨著吸附劑投加量和溫度的增加而減小。不同ACF用量和溫度下，ACF吸附兩種廢水的吸附過(guò)程均符合準(zhǔn)二級(jí)

5、動(dòng)力學(xué)模型；熱力學(xué)和活化能參數(shù)表明，ACF吸附苯酚是一個(gè)自發(fā)的放熱過(guò)程，ACF對(duì)廢水中苯酚的吸附以物理吸附過(guò)程為主。采用自制的ACF吸附柱對(duì)兩種廢水的動(dòng)態(tài)吸附與脫附性能作了考察。動(dòng)態(tài)吸附實(shí)驗(yàn)表明，ACF填充量相同時(shí)，由于石化廢水中油類(lèi)等物質(zhì)的存在，在出水量500mL為之前石化廢水經(jīng)過(guò)吸附柱后的出水中苯酚濃度要高于模擬廢水，說(shuō)明石化廢水中的油類(lèi)物質(zhì)與苯酚產(chǎn)生了競(jìng)爭(zhēng)吸附。動(dòng)態(tài)脫附實(shí)驗(yàn)表明，模擬廢水中被吸附的苯酚從ACF上脫附的速率高于石化廢

6、水中被吸附的苯酚，兩種水樣在達(dá)到脫附平衡后，平衡脫附液中石化廢水中苯酚濃度也要高于模擬廢水。油類(lèi)等物質(zhì)占據(jù)了ACF中一些的孔道，阻礙了苯酚分子的脫附。楊洋：吸附催化氧化技術(shù)處理廢水中苯酚的研究IllIIIIIM11111111IIIIINilIII—AbstractY2632406Phenolsareaclassofhighlytoxicanddifficulttodegradeorganicmatter，thetreatmentofp

7、henolicwastewateristhefocusofthestudyWastewaterdischargerequirementshavebecomemorestringentduetothedemandforenvironmentalprotectionThus，asingletreatmentmethodisdifficulttomeettheneedsofenterprisesThecombinationofavariety

8、ofwatertreatmenttechnologyhasbecomeoneofthehotresearchdirectionsInthispaper，thetechnologythatcombinedadsorptionwithcatalyticoxidationareappliedindepthtreatmentofphenolinsimulatedwastewaterandpetrochemicalwastewater，thati

9、s，centralizedphenolofpretreatedwastewaterbytheadsorptionmethodfirstly，thentheadsorbedphenolaredesorbedtohandlewithcatalyticoxidationThereby，greatlythebiochemicaltreatmenttimecanbereducedandtheefficiencyofwastewatertreatm

10、entcanbeimproved。Activatedcarbonfiber(ACF)asanovelfunctionalmaterialcanserveasaneffectiveadsorbentfortreatingwastewater,ithasremarkableadvantages：alargesurfacearea，narrowporesizedistribution，abundantmicropores，fastadsorp

11、tionanddesorption，mildregenerationconditions，etcInthispaper，ACFusedasadsorbent，phenolsolutionusedassimulatedwastewater，theinfluenceoftheACFadsorptionpropertiesofphenolwereinvestigatedindifferentconditions，andtheeffectofp

12、henoldesorptioninNaOHsolutionisalsoinvestigatedTheresultsshowthattheadsorptionrateofphenolinitialrapidonACF，generally30mintoclosetoequilibriumThetemperaturehasalittleeffectontheACFadsorptionproperties，raisingthetemperatu

13、reisnotconducivetotheadsorptionofphen01IncreasingtheACFdosagecanpromotephenolremovalrate，buttheequilibriumadsorptioncapacitydecreasedtocauseACFlowerutilizationInacidandneutralmedium，theadsorptionpropertybeRerthanalkaline

14、mediumSaturatedACFCallberegeneratedbymassconcentrationof3％sodiumhydroxideat60“C，ACFadsorptionperformancearestableandmaintainhighlevelafter10timesrepeatedadsorptionanddesorptionexperimentsUsingACFasadsorbent，thecomparativ

15、estudyintheadsorptionprocessofphenolofpetrochemicalwastewaterandsimulatedwastewateronACFhasbeeninvestigated，mainlyfromtheadsorptionisotherms，adsorptionkineticsanddynamicadsorptionanddesorption，etcAdsorptionisothermswered

16、eterminedandmodeledwithLangmuirandFreundlichadsorptionmodelTheresultsshowedthattheadsorptionprocessofphenolfromsimulatedwastewateronACFfitstheLangmuirmonolayeradsorption，buttheadsorptionprocessofphenolfrompetrochemicalwa

17、stewaterfitsFreundlichisothermmodelberetItismainlyduetotheoilandothersubstancesinpetrochemicalwastewateraffecttheadsorptionofphenolonACFsurface，adsorptionprocessisnolongerasimplemonolayeradsorptionKineticexperimentsshowt