Removal of Atrazine from Aqueous Solutions Using HNO 3 Treated Oil Palm Shell-Based Adsorbent

Transcription

1 Rmoval of Arazin from Aquous Soluions Using HNO 3 Trad Oil Palm Shll-Basd Adsorbn I.A.W. Tan, L.L.P. Lim, and K.T. Lim Absrac Acivad carbon is a prominn marial for adsorpion of arazin, howvr is usag is rsricd du o h high cos. Thus, alrnaiv adsorbn drivd from agriculural was has bn invsigad. This sudy focusd on h fasibiliy of dvloping low-cos adsorbn from oil palm shll for rmoval of arazin from aquous soluions. Th adsorbn was drivd from oil palm shll using HNO 3 ramn. Th drivd adsorbn was characrizd for h surfac morphology and surfac chmisry using SEM and TIR, rspcivly. Adsorpion quilibrium xprimns wr carrid ou in bach mod o invsiga h ffcs of adsorbn dosag, iniial concnraion, conac im and soluion ph on h adsorpion upak of arazin on h adsorbn. Th rundlich isohrm modl showd a br corrlaion compard o Langmuir isohrm modl o fi h quilibrium daa, giving h adsorpion capaciy of mg/g(l/mg) 1/n a 30 o C. Arazin soluions wih ph 2 showd h highs adsorpion upak of 17.68%. Th highs prcnag rmoval was found o b 6.06% wih adsorbn dosag of 2 g/200 ml. Th adsorpion procss was found o follow h psudo-scond-ordr kinic modl mor han h psudo-firs-ordr kinic modl as h corrlaion cofficins, R 2 for h psudo-scond-ordr kinic modl wr rlaivly highr for all arazin concnraions, ranging from Th adsorbn drivd was provn o b fasibl in rmoving arazin from aquous soluions. Kywords: Oil Palm Shll, Arazin, Adsorpion, Isohrm, Kinic I I. INTRODUCTION NTOXICATIONS ascribd o psicids hav bn simad o b as high as 3 million cass of acu and svr poisoning annually. Hnc, h imporanc of alrnaivs o prvn many of h psicids poisonings, conaminaions and rmov psicids from h aquous soluions ha xis oday is of major concrn [1]. Arazin,2-chloro-4-(hylamino)-6- (isopropylamino)-s-riazin, is an organic compound consising of an s-riazin-ring which is widly usd as hrbicid. Arazin is usd o sop pr- and pos-mrgnc broadlaf and grassy wds in major crops [2] [3]. Th compound is boh ffciv and inxpnsiv, and hus is wll-suid o producion sysms wih vry narrow profi margins, as is ofn h cas wih maiz. Th wid us of arazin howvr ngaivly impacs h war qualiy and poss nvironmnal polluion, vn hough is us is in a limid amoun of compound dspi is us is wihin h prmid dosag. Adsorpion chniqu is favourabl for arazin rmoval du o is simpliciy as wll as h availabiliy of a wid rang of adsorbns. Commrcial acivad carbon has high adsorpion capaciy for rmoval of arazin. Howvr, h major drawback is is high cos of producion, making is usag in rmoval of arazin lss araciv. Thus, hr is a dmand for alrnaiv adsorbns, which ar mad of inxpnsiv marials such as agriculural wass. Sinc oil palm shll is abundan in Malaysia, hrfor his sudy aims o invsiga h fasibiliy of using oil palm shll-basd low-cos adsorbn for rmoval of arazin from aquous soluions. II. MATERIALS AND METHODS 2.1 Marials and apparaus In his rsarch, oil palm shll was slcd as raw marial o prpar h lowcos adsorbn. Th oil palm shll was collcd from dral Land Consolidaion and Rhabiliaion (lcra) palm oil mill, Sarawak and h granular acivad carbon of 6x12 msh siz was providd by Bravo Grn Sdn Bhd. Analyical grad of arazin was usd for h prparaion of sock soluion. Disilld war was usd in h prparaion of all soluions and adsorbn sampl purificaion. Volumric flask of 1000 ml was usd o prpar sock soluion. Conical flasks of 500 ml wr usd in bach adsorpion xprimns. Ivy A. W. Tan is wih h Dparmn of Chmical Enginring and Enrgy Susainabiliy, aculy of Enginring, Univrsii Malaysia Sarawak, Koa Samarahan, Sarawak, Malaysia. (-mail: awian@fng.unimas.my). Lonard L. P. Lim is wih h Dparmn of Civil Enginring, aculy of Enginring, Univrsii Malaysia Sarawak, Koa Samarahan, Sarawak, Malaysia. (-mail: llplonard@fng.unimas.my). Kwang Ting Lim is wih h Dparmn of Mchanical and Manufacuring Enginring, aculy of Enginring, Univrsii Malaysia Sarawak, Koa Samarahan, Sarawak, Malaysia. (-mail: ridilim88@homail.com). 17

2 Plasic pips of 3 ml wr usd in h xprimn for addiion of sulphuric acid (H 2 SO 4 ) and sodium hydroxid (NaOH) o adjus h soluion ph and o xrac h sampl. Th concnraions of arazin wr analyzd by using a UV-visibl spcrophoomr (Shimadzu UV mini 1240). 2.2 Prparaion of adsorbn Th oil palm shll was washd wih doubl disilld war o rmov forign impuriis. Th sampl was drid in an ovn a 110 o C for 24 h. Th sampl was hn coold o room mpraur, crushd and sivd in sainlss sl msh siv o obain paricls sizd wihin h rang of mm. Th sampl was washd again horoughly wih doubl disilld war o rmov h fibrs and fin paricls, hn drid a 45 o C for 4 h in an ovn. 50 g of h sampl was soakd in 200 ml of n-hxan o rmov rsidu oil from h oil palm shll surfac. Thn, h sampl was chmically rad wih 200 ml of 0.1 M niric acid for 1 h, followd by soaking in 200 ml of mhanol for 1 h o rmov inorganic and organic mars from h surfac of h adsorbn [4]. Th adsorbn sampl was washd wih ho war unil h soluion ph rachd 7, hn subjcd o hrmal ramn in an ovn a mpraur of 200 o C for 6 h o incras h surfac ara. Th chmically and hrmally rad adsorbn was sord in a sampl bol for furhr characrizaion and analysis. 2.3 Characrizaion of adsorbn Th oil palm shll-basd adsorbn was characrizd using scanning lcron microscop (SEM) (JEOL JSM-6390LA) o sudy h surfac morphology of h adsorbn bfor and afr h chmical ramn and also afr h adsorpion of arazin whras ourir ransform infrard (TIR) spcrophoomr (Shimadzu IRAffiniy-1) was usd o idnify h funcional groups prsn on h surfac of h oil palm shll-drivd adsorbn. 2.4 Bach adsorpion sudis Adsorpion quilibrium xprimns wr carrid ou in bach mod o invsiga h ffcs of iniial concnraion of arazin, conac im, adsorbn dosag and iniial soluion ph on h adsorpion upak of arazin by oil palm shll-basd adsorbn. Th sock soluion of arazin was prpard by dissolving 30 mg of analyical grad arazin in powdr form in 1% of mhanol. Th sock soluion of arazin of 30 mg/l was dilud using disilld war o h rquird concnraions in h rang of 5-30 mg/l. Adsorpion xprimns o sudy h ffc of iniial concnraion wr conducd using 200 mg of adsorbn wih 200 ml of arazin soluion of diffrn iniial concnraions a consan mpraur (30 o C). Th ffc of adsorbn dosag was sudid using dosag rang of 0.2g-2g in 200 ml of arazin soluion wih iniial concnraion of 5 mg/l a consan mpraur (30 o C). Th ffc of soluion ph on arazin adsorpion was invsigad by conacing 200 mg of adsorbn wih 200 ml of arazin soluion wih iniial concnraion of 5 mg/l a varying iniial ph in h rang of 2-12 a consan mpraur (30 o C). Adsorpion quilibrium xprimns wr rpad by using acivad carbon undr h sam condiion o invsiga h ffcs of iniial concnraion of arazin on h adsorpion upak of arazin by acivad carbon. This was don o compar h ffcivnss of h oil palm shll-basd adsorbn in rmoving arazin wih h commrcial acivad carbon. Th absorbanc of arazin a maximum wavlngh of 222 nm was plod agains arazin concnraion o obain a calibraion curv for drminaion of arazin concnraions. Th adsorpion upak a im, q (mg/g), was xprssd using (1) [5]: q ( C 0 C ) V / W (1) whr q is h amoun of arazin adsorbd by adsorbn (mg/g), C is h iniial concnraion of arazin (mg/l), 0 C is h concnraion of arazin a any im (mg/l), V is h soluion volum (l), and W is h mass of adsorbn usd (g). 2.5 Adsorpion isohrms Th shap of an adsorpion isohrm xprsss h spcific rlaionship bwn h concnraion of adsorba and h adsorpion capaciy of h adsorbn and rflcs h possibl mod for h adsorpion procss. Th Langmuir modl is valid for monolayr adsorpion, applicabl o homognous adsorpion on a surfac. Th linar form of h Langmuir adsorpion isohrm quaion (2) can b wrin as following [6]: C / q 1/ QmK L (1/ Qm ) C (2) whr C is h quilibrium concnraion of h adsorba (mg/l), q is h amoun of adsorba adsorbd pr uni mass of adsorbn (mg/g), Q and m K ar Langmuir consans rlad o adsorpion capaciy (mg/g) and ra of adsorpion (l/mg), L rspcivly. Th plo of C / q agains C would giv h valu of Q and m K. L Th rundlich isohrm is an mpirical quaion basd on h assumpion of mulilayr formaion of adsorba ono a hrognous surfac of adsorbn. I assums ha srongr binding sis ar occupid firs and binding srngh dcrass wih incrasing dgr of si occupaion. Th linar form of rundlich isohrm quaion (3) can b wrin as following [7]: ln q ln K (1/ n) ln C (3) whr K and n ar rundlich consans which K is h adsorpion capaciy of h adsorbn (mg/g(l/mg)) 1/n and n is a masur of favorabiliy of h adsorpion procss. Th plo of ln q agains ln C would giv h valu of K and n. 18

3 2.6 Adsorpion kinics To xamin h mchanism of h adsorpion procss, wo kinic modls wr usd o fi h xprimnal daa. A simpl kinic analysis of h adsorpion was valuad by mploying h psudo-firs-ordr (4) and psudo-scond-ordr (5) quaions [6]: ln( q q ) ln q k1 (4) whr q and q ar h amouns of adsorba adsorbd (mg/g) a quilibrium and a im, rspcivly, and k is h 1 adsorpion ra consan (min -1 ). Consan k and 1 q could b calculad from h plo of ln( q q ) vrsus im. 2 / q 1/( k2q ) (1/ q ) (5) whr k 2 is h ra consan of scond-ordr adsorpion (g/mg min). Th plo of / q agains would giv h valu of k 2 and q. III. RESULTS AND DISCUSSION 3.1 Characrizaion of adsorbn. Th SEM imags of h raw oil palm shll, oil palm shll-basd adsorbn rad wih HNO 3, acivad carbon and oil palm shll-basd adsorbn afr adsorpion of arazin ar prsnd in igurs 1(a) (d), rspcivly. rom igur 1(a), h SEM micrograph shows dir-covrd and unclar pors on h surfac of raw oil palm shll. Thr ar vry small pors prsn on h surfac of h raw oil palm shll. Chmical ramn wih HNO 3 on h oil palm shll-basd adsorbn rsuld in h dvlopmn of pors, as shown in igur 1(b). Th rsuls showd ha h surfac of h HNO 3 rad adsorbn was highly porous as compard o h raw oil palm shll. This provd ha HNO 3 had h ponial in changing h surfac srucur of h adsorbn by is chmical propris in corroding h surfac of h oil palm shll and incrasd h porosiy ono i. Bsids, acid ramn migh dissolv h minrals from h adsorbn surfac, hus incrasd h por volum and surfac ara of h adsorbn [4]. Manwhil, h pors found on h surfac of h acivad carbon wr rlaivly largr. I could b sn ha h xrnal surfac of acivad carbon was full of clar and dp pors, as illusrad in igur 1(c). rom igur 1(d), i could b obsrvd ha h pors dvlopd on h surfac of h adsorbn wr bing occupid by h arazin molculs. (a) (b) (c) (d) igur 1: SEM imags of (a) raw oil palm shll, (b) oil palm shll-basd adsorbn rad wih HNO 3, (c) acivad carbon and (d) oil palm shll-basd adsorbn afr arazin adsorpion. rom h TIR spcrum obaind, h raw oil palm shll showd six major absorbanc paks wih high innsiy a cm -1, cm -1, cm -1, cm -1, cm -1 and cm -1 as wll as wo paks a cm - 1 and cm -1 wih lowr innsiy. Th pak a cm -1 migh b aribud o NH srching mod of amins or amids, whil h pak a cm- 1 was aribud o C-H aliphaic srching vibraion du o h xisnc of aliphaic groups in h oil palm shll. Th pak around cm 1 could b ascribd o C=C srching vibraion in aromaic rings [5]. Th pak a cm -1 was aribud o srong P-O-C inracion wih h surfac of h unrad oil palm shll. This indicad ha h absorbanc paks wr h srongs and had h highs frquncis for aliphaic compounds [5]. Th TIR spcrum for HNO 3 rad oil palm shll showd six absorbanc paks wih high innsiy a cm -1, cm -1, cm -1, cm -1, cm -1 and cm -1 as wll as wo paks wih lowr innsiy a cm -1 and cm -1. Th srong pak a cm -1 was ypical of vibraion originaing from O H srching frquncy of hydroxyl funcional groups wih hydrogn bonding [8]. Th pak a cm -1 could b assignd o C=C srching of aromaic rings polarizd by oxygn aoms bound nar on of h C aoms whil h spcra rvald a pak a cm -1 19

4 which indicad h prsnc of carboxylic group [9]. In h HNO 3 ramn of oil palm shll-basd adsorbn, unsabl oxygn groups (.g. carboxyl groups) ar dcomposd and only hydroxyl and carbonyl groups rmaind whrby h succssiv physical and chmical ramn has hlpd in ransforming a non-porous oil palm shll o a wll dvlopd adsorbn wih favorabl surfac chmisry [9]. Th pak occurrd a cm -1 was ascribd o R OH srching of hydroxyl groups. Th low innsiis obsrvd for h paks could b h rsul of h liminaion of hs groups by carbonizaion and acivaion [10]. Th prsnc of OH groups impard ngaiv charg o h oil palm shll surfac [10]. Th highs innsiy pak for acivad carbon was obaind a cm-1 and a lowr innsiy pak was obaind a cm -1. Th pak occurrd a cm -1 was aribud o C=C srching vibraion of aromaic rings whil h pak a cm -1 was ascribd o NH srching mod of srong OH alcohols or phnols groups [6]. 3.2 Effc of conac im and iniial arazin concnraion Th adsorpion of arazin by oil palm shll-basd adsorbn and acivad carbon was sudid a diffrn iniial concnraions of arazin of 5, 10, 15, 20, 25 and 30 mg/l a 30 o C. Basd on h rsuls obaind by using UV visibl spcrophoomr (Shimadzu UV mini 1240), a graph of adsorpion upak vrsus h adsorpion im a various iniial concnraions of arazin for oil palm shll basd-adsorbn and acivad carbon was plod as shown in igur 2 and igur 3, rspcivly. Th adsorpion upak of h oil palm shll-basd adsorbn and acivad carbon was found o incras wih h iniial concnraion of arazin. Th incras in iniial concnraion of arazin has ovrcom h rsisanc o h mass ransfr of arazin bwn h aquous and solid phass which also nhancd h inracion bwn arazin and adsorbn as wll as acivad carbon [11]. As h iniial concnraion of arazin incrasd, i incrasd h concnraion gradin which acd as h driving forc for h adsorpion procss [12]. igur 2 shows ha h im for h arazin soluion wih iniial concnraion of 5 mg/l and 10 mg/l o rach quilibrium was 180 min whil h arazin soluions wih iniial concnraion of 15 mg/l o 30 mg/l rquird longr im o rach quilibrium. This was du o h fac ha a low concnraions, h raio of availabl surfac o h iniial arazin concnraion was largr which had asd h adsorpion procss, hrfor i was asir for h procss o aain quilibrium. Howvr, in h cas of highr concnraions, his raio was rlaivly lowr, hus mor im was ndd o achiv quilibrium. Th adsorpion upak of arazin on acivad carbon as shown in igur 3 rvald ha h adsorpion procss was qui rapid iniially and rachd quilibrium afr 23 h. Th iniial high adsorpion ra was du o h abundanc of fr binding sis[11]. Th adsorpion upak of arazin molculs by h acivad carbon and h im rquird for sablishmn of quilibrium suggsd h ffcivnss of acivad carbon in rmoving arazin from aquous soluions. igur 2: Adsorpion upak of arazin a various iniial concnraions on oil palm shll-drivd adsorbn igur 3: Adsorpion upak of arazin a various iniial concnraions on acivad carbon. 3.3 Effc of adsorbn dosag Th ffc of h adsorbn dosag was sudid a 30 o C by varying h adsorbn amoun from 0.2 o 2 g wih iniial arazin concnraion of 5 mg/l. I could b sn from igur 4 ha iniially h prcnag rmoval of arazin incrasd vry sharply wih h incras in adsorbn dosag. This rnd was xpcd bcaus as h adsorbn dosag incrasd, h numbr of adsorbn paricls incrasd and hus mor arazin molculs wr aachd o hir surfacs [12]. Th prcnag of rmoval incrasd rapidly up o 6 % wih h incrasing amoun of adsorbn from 0.2 o 2 g. Th iniial ris in adsorpion wih adsorbn dosag was du o a srongr driving forc and largr surfac ara. Wih a ris in adsorbn dosag, hr was lss corrsponding incras in adsorpion rsuling from lowr adsorpiv capaciy uilizaion of adsorbn [9]. 3.4 Effc of soluion ph Bach adsorpion xprimns wr prformd a diffrn soluion ph ranging from ph 2 o 12 a 30 ºC. Th iniial concnraion of arazin was 5 mg/l and roaion spd of h shakr was fixd a 180 rpm. Th prcnag of arazin rmoval dcrasd wih an incras in h soluion ph, as shown in igur 5. This rnd occurrd possibly du o a low ph, h surfac of h adsorbn would b surroundd by h hydronium ions, which migh nhanc h arazin inracion wih binding sis of h adsorbn by grar araciv forcs and hnc improvd is upak on polar adsorbn [13]. 20

5 igur 4: Effc of adsorbn dosag on arazin rmoval. igur 5: Effc of soluion ph on arazin rmoval. 3.5 Adsorpion isohrms Th sudy of h adsorpion isohrm is fundamnal, and plays an imporan rol in h drminaion of h adsorpion capaciy of an adsorbn, on of h mos imporan criria in slcing a suiabl adsorbn [7]. In his sudy, wo isohrm modls wr usd in fiing h quilibrium daa, namly h Langmuir and rundlich isohrm modls. Th Langmuir isohrm modl is valid for monolayr adsorpion, applicabl o homognous adsorpion on a surfac assuming ha all h adsorpion sis hav qual solu affiniy and ha adsorpion a on si dos no affc h adsorpion a an adjacn si [14]. Th rundlich isohrm is an mpirical quaion basd on h assumpion of mulilayr formaion of adsorba ono a hrognous surfac of adsorbn. I assums ha srongr binding sis ar occupid firs and binding srngh dcrass wih incrasing dgr of si occupaion [8]. Th R 2 valus obaind for Langmuir isohrm modl was 3x10-5 for oil palm shll-basd adsorbn and for acivad carbon. This indicad ha h adsorpion of arazin ono h adsorbn and acivad carbon did no fi wll o h Langmuir isohrm modl. Th linarizd form of rundlich isohrm modl was usd o valua h adsorpion capaciy of h adsorbn and acivad carbon. Th R 2 valus obaind for rundlich isohrm modl wr and rspcivly for h adsorbn and acivad carbon, which indicad ha rundlich isohrm modl br fid h quilibrium daa. Th Langmuir and rundlich consans wr calculad from (2) and (3), rspcivly and ar summarizd in Tabl 1. Th adsorpion capaciy, K and innsiy n for adsorpion of arazin on oil palm shll-basd adsorbn wr (mg/g)(l/mg) 1/n and 0.98, rspcivly. Th valu of n which was lss han on indicad ha h adsorpion of arazin on oil palm shll-basd adsorbn was lss favorabl as compard o acivad carbon. Howvr, his rsul is consisn wih h liraur whr Alam al. [15] also rpord ha h adsorpion of arazin using various adsorbns wr wll rprsnd by rundlich isohrm modl. Tabl 1: Langmuir and rundlich consans for adsorpion of arazin on oil palm shll-basd adsorbn and acivad carbon. Adsorbns Langmuir rundlich Q m (mg/g) K L (l/mg) R 2 K (mg/g)(l/mg) 1/n n R 2 Oil palm shll-basd adsorbn E-0.5 3E Acivad carbon E Adsorpion kinics Adsorpion kinics is a crucial characrisic from h poin of viw of analyzing h fficincy of adsorpion procsss which dscribs h solu upak ra and vidnly his ra conrols h rsidnc im of adsorbn upak a h solid soluion inrfac including h diffusion procss [13]. Th mchanism of adsorpion dpnds on h physical and chmical characrisics of h adsorbn as wll as on h mass ransfr procss [16]. Th Lagrgrn s psudo-firs-ordr and psudoscond-ordr modls [6] wr usd o invsiga h adsorpion kinics daa in ordr o drmin h mchanism of adsorpion procss in his sudy. Th psudo-firs-ordr and psudo-scond-ordr consans for oil palm shll-basd adsorbn and acivad carbon ar lisd in Tabl 2 and Tabl 3, rspcivly. Basd on h psudo-firs-ordr plo, h R 2 valus obaind wr rlaivly low and h xprimnal q valus did no agr wih h calculad valus obaind from h linar plo. This indicad ha h adsorpion of arazin ono h adsorbn did no fi ino h psudo-firs-ordr quaion. Howvr, h R 2 valus obaind for h psudo-firs-ordr modl wr grar han 0.99 for acivad carbon and h q calculad by his modl wr clos o hos obaind from h xprimns. Similar rnd has bn rpord by Gupa al. [9] for psicid rmoval from waswar using acivad carbon prpard from was rubbr ir. As h siz of arazin and mhyl parahion was almos h sam, hir ra consans should also b similar, and h xprimnal ra consans wr found o b narly h sam [9]. Th psudo-scond-ordr kinic modl prdicd h bhavior ovr h whol rang of adsorpion and was in agrmn wih chmisorpion bing h ra conrolling sp [17]. Th R 2 valus obaind for h psudo-scond-ordr kinic modl wr rlaivly high for all arazin concnraions using h oil palm shll-basd adsorbn. This furhr confirmd ha h psudo-scond-ordr kinic modl was suiabl in dscribing h adsorpion of arazin ono h adsorbn. Howvr, an invrs rlaionship was obsrvd for acivad carbon which showd lowr R 2 valus for psudo-scond-ordr kinic modl, which rangd bwn

6 Tabl 2: Psudo-firs-ordr and psudo-scond-ordr consans for adsorpion of arazin on oil palm shll-basd adsorbn. Exprimnal q Psudo-firs-ordr modl Psudo-scond-ordr modl Iniial concnraion (mg/l) (mg/g) k 1 (min -1 ) q (mg/g) R 2 k 2 (g/mg.min) q (mg/g) R E Tabl 3: Psudo-firs-ordr and psudo-scond-ordr consans for h adsorpion of arazin on acivad carbon. Iniial concnraion Exprimnal q Psudo-firs-ordr modl Psudo-scond-ordr modl (mg/l) (mg/g) k 1 (min -1 ) q (mg/g) R 2 k 2 (g/mg.min) q (mg/g) R E E ,831E E E E IV. CONCLUSIONS Th HNO 3 ramn faciliad in h dvlopmn of a wll dvlopd porous adsorbn and ingraion of carbonyl and hydroxyl funcional groups ono h adsorbn surfac. Ths could b obsrvd hrough h SEM micrographs and h TIR spcrum, rspcivly. Th opimum ph obsrvd was a ph 2 which gav h highs arazin rmoval of 17.68% whras wih adsorbn dosag of 2 g, h highs arazin rmoval was found o b 6.06%. Th quilibrium analysis was don using Langmuir and rundlich isohrm quaions. Th rundlich isohrm modl showd a br corrlaion compard o Langmuir isohrm modl in fiing h quilibrium daa, giving h maximum adsorpion capaciy of mg/g(l/mg) 1/n a 30 o C. Th adsorpion procss was found o follow h psudo-scond-ordr kinic modl for h oil palm shll-basd adsorbn which suggsd ha h adsorpion ra was dpndn mor on h availabiliy of h adsorpion sis han h concnraion of h arazin soluions. Th prsn sudy showd ha oil palm shll could b usd as a ponial prcursor for h prparaion of low-cos adsorbn for rmoval of arazin from aquous soluions. ACKNOWLEDGMENT Th auhors acknowldg h rsarch grans providd by Osaka Gas oundaion in Culural Exchang (OGICE) Rsarch Gran Schm and Univrsii Malaysia Sarawak undr Small Gran Schm 02(S84)/820/2011(18). Th auhors would lik o hank Bravo Grn Sdn. Bhd. for providing h acivad carbon. REERENCES [1] L.S. Tan, Nanofilraion ramn for psicids rmoval:a cas sudy for arazin and dimhoa, Masrs Dissraion, Univrsiy Scinc Malaysia, [2] T.S. Jamil, T.A. Gad-Allah, H.S. Ibrahim, and T.S. Salh, Adsorpion and isohrmal modls of arazin by zoli prpard from Egypian kaolin, Solid Sa Scinc, vol. 13, pp , [3] A. Mudhoo, and V.K. Garg, Sorpion, ranspor and ransformaion of arazin in soils, minrals and composs: a rviw, Pdosphr, vol. 21, pp , [4] G.Z. Mmon, M.I. Bhangr, and M. Akhar, Th rmoval fficincy of chsnu shlls for slcd psicids from aquous soluions, Journal of Colloids and Inrfac Scinc, vol. 315, pp , [5] J.M. Salman, V.O. Njoku, and B.H. Hamd, Adsorpion of psicids from aquous soluion ono banana salk acivad carbon, Chmical Enginring Journal, vol. 174, pp , [6] I.A.W. Tan, A.L. Ahmad, and B.H. Hamd, Adsorpion of basic dy on high-surfac-ara acivad carbon prpard from coconu husk: Equilibrium, kinic and hrmodynamic sudis, Journal of Hazardous Marials, vol. 154, pp , [7] D.Z. Chn, J.X. Zhang, and J.M. Chn, Adsoprion of mhy r-buyl hr using granular acivad carbon: Equilibrium and kinic analysis, Inrnaional Journal of Environmnal Scinc and Tchnology, vol. 7, pp , [8] V.O. Njoku, and B.H. Hamd, Prparaion and characrizaion of acivad carbon from corncob by chmical acivaion wih H3PO4 for 2,4- dichlorophnoxyacic acid adsorpion, Chmical Enginring Journal, vol. 173, pp , [9] V.K. Gupa, B. Gupa, A. Rasogi, S. Agarwal, and A. Nayak, Psicids rmoval from was war by acivad carbon prpard from was rubbr ir, War Rsarch, vol. 45, pp , [10] J.M. Salman, V.O. Njoku, and B.H. Hamd, Bnazon and carbofuran adsorpion ono da sd acivad carbon:kinics and quilibrium, Chmical Enginring Journal, vol. 173, pp , [11] K.L. Chang, J.H. Ling, and S.T. Chn, Adsorpion sudis on h rmoval of psicids (carbofuran) using acivad carbon from ric sraw agriculural was, World Acadmy of Scinc, Enginring and Tchnology, vol. 76, pp , [12] P.S. Kumar, R. Gayahri, and R.P. Arunkumar, Adsorpion of (III) ions from aquous soluion by Bngal gram husk powdr: Equilibrium isohrms and kinic approach, Elcronic Journal of Environmn, Agriculur and ood Chmisry, vol. 9, pp , [13] G.Z. Mmon, M.I. Bhangr, M. Akhar,.N. Talpur, and J.R. Mmon, Adsorpion of mhyl parahion psicid from war using warmlon pls as a low cos adsorbn, Chmical Enginring Journal, vol. 138, pp , [14] S.H. Lin, and R.S. Juang, Adsorpion of phnol and is drivaivs from war using synhic rsins and low-cos naural adsorbns: A rviw, Journal of Environmnal Managmn, vol. 90, pp , [15] J.B. Alam, A.K. Dikshi, and M. Bandyopadhyay, Efficacy of adsorbns for 2,4-D and arazin rmoval from war nvironmn, Global Ns:h Inrnaional Journal, vol. 2, pp , [16] T.K. Naiya, P. Chowdhury, A.K. Bhaacharya, and S.K. Das, Saw dus and nm bark as low-cos naural biosorbn for adsorpiv rmoval of Zn(II) and Cd(II) ions from aquous soluions, Chmical Enginring Journal, vol. 148, pp , [17] Y.S. Ho, and G. Mckay, Sorpion of dy from aquous soluion by pa, Chmical Enginring Journal, vol. 70, pp ,