BAO CAO T 6 M TAT " H O I N S H I KHOA HOC K* NIf U 40 NAMflmS-2015) T H A N H LAP Vlf N HAN LAM KHOA HOC VA CfiNG NGHf VlfT NAM'
XAC B I N H B i l u K I | N SINH T R l / O W G V A T 6 N G H Q T LlPfT OT KHU£ T A O ChaetiKeros grociffs THtCH H ( r p l A M N G U b N N G U Y I N L i | U CHO BIODIESEL
Ld Thj Thdy Al'", OInh Thi Lan Anh', Hodng Thdi l ^ , Nguyin Anh Ode*
'Win Ddu khi vin Nam, Khdch son Thanh Ba, a Blnh Thgnh, Tp.HCM, alltt.rni!eevol.ovn.vn 'Bglhoc Khoa hoc TV nhlin, thdnh phi Ho ChlMlnh, 227 Nguyin Vdn Or, M, 05, Tg.Hi ChlVlnh
Tinh dp Ihiit. Khue tdo Chaetoceros gracilis Id lodi cd t^c d0 phdt hiin nhanh, dl nhdn nudi, vd td Idu dd dugc chd trpng nhdn nudi phvic vy cdc d6i hnjng thdy san d nude ta. Tren thd gjdi, vdi chuong tthih nghien cdu vi tdo cho nhien li$u sinh hijc cung
<H chd f khdo sdt nhdn nudi khud tdo (Chuong trinh cdc Lodi Thuy sdn (Aquatic Species Program) cda Hoa Kj-, ndm 1978 vd chuong trinh do T$p dodn Dau khi Thdi Lan PTT ket hsfp Dp hpc King Mongkut, ndm 2011). Nghien cdu ndy nhdm ddnh gii ti4m ndng cda chdng Chaetoceros gracilis thich hgrp ldm nguin nguyen li$u cho hiosiesel thdng qua d ^ dilm sinh trudng vd d$c tinh lipit sinh t6ng hgip.
Phiamgphip nghiin citu
Cdng trinh nghidn cdu ndy de c^ chi tiet \h dilu ki|n t6i uu cho nhdn smh khIi vd dieu kien dp Ivc gidm Hinh dudng kich thich t6ng hgp lipit d khue tdo Chaetoceros gracilis d qui md phdng thi nghi$m. Cdc ylu t6 dnh hudng din smh trudng dugc khdo sdt gim: nong dg CO2, cudng dO chilu sdng, pH, dd m|n, nong dO dmh dudng nito vd phltpho. Quy ho^h thvrc nghidm dugc thiit kl theo phuong phdp Taguchi g6m 25 nghi^ thde theo mdng tr\ic glao L'25 orthoairay vd thdng so ddnh gid Id tic d$ tdng trudng vd tn;>ng lugng khd smh khIi. Cdc so li^u dugc phdn tich th6ng kl bdng phin mim Mmitabld (Stat - DOE - Taguchi). Th\rc nghi?m xdc dinh dilu ki$n dp \\>c thich hgp cho tich lijy lipit dugc bl tri chgn Igc vd gidm thilu ylu t l dinh dudng (nito/photpho/silic); vd th\rc hi$n phuong thiic nudi hai giai doan: Giai dogn nhdn nudi gidu dinh duong, sau dd smh khdi dugc chuyin vdo dilu ki$n mdi trudng gidm thilu dinh dudng. Dien bien tich luy Upit dugc khdo sdt theo dgng hgc sinh trudng. Lipit ting sl dugc chilt td smh khdi khd theo phuong phdp cda Bligh vd Dyer (1959) vd hieu chinh quy trinh chilt theo Takagi vd cdng svt (2006). Xdc djnh am dg theo TCVN4326:2001. Djnh lugng Upit noi bdo blng phuong phdp chilt vd cdn khIi lugng.
Chuyin este smh khIi khd vi tdo dugc th\rc hi$n theo phuong phdp AGAC 996.06, AOAC 969.33 vd cdng trtnh cda Nascunento vd cdng su (2013). Lipit ting dugc chilt trong hexan, axit bdo dugc xd phdng hda bdng NaOH/methanol, vd metyl hda vdi
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BAO CAO T 6 M TAT "HOI N G H I KHOA HOC K i NIf M 40 NAM I197S-2015) T H A N H LAP VlfN HAN LAM KHOA HOC VA CONG NGHf v i f r N A \ r
BF3/methanol Axit bdo metyl este dugc chilt bdng hexan. Thdnh phin axIt b&) metyl este dugc phdn tich bdng sdc k^ khIi phA GC-MS vd GC-FID vdi chuin Supelco 37 FAME mix (Supelco-47885, Sigma-Aldrich).
Tdm til kit qui vi Ihio lu^
Kit qud khdo sdt nlng dd CO2 thich hgp eho tdng trudng da chi ra toe dd tdng trudng d Chaetoceros gracilis tdng h^ren tinh vdi cac nlng dO CO2 Id 0,04%, 1% vd 2%; vd Khd ndng khdng CO2 d chdng ndy d^t mdc 4%. T^ nlng dd CO2 toi liu cho sinh taldng (2%), tic dg tang hudng ^ =l,386/ngdy, thdi gian thi h? Td = 12gid, hgng lugng khd smh khIi tii da la 0,62gani/Ut Vdy vdi cdc chi tilu tdng trudng d Chaetoceros gracilis: tic dd tdng trudng nhanh (cao hon ^ = 0,693Algdy), thdi gian the h$ ngdn (it hon 24gid), trgng lugng khd smh khoi cao (hon 0,5gani/lit), chung ndy ddp dng nhOng tilu chi ca bdn dl nhan djnh lodi tilm ndng cho nhdn nudi.
Kit qud khdo sdt ddng hgc smh trudng vd tii im hda sinh khIi ^ xdc dinh dugc dieu ki$n nudi thich hgp Id: nitrat 27,3-54,7 mg/l; silic 6,9 -13,8 mg/l; chilu sdng 3- lOkbt; dd mdn 20-35%o, pH 6,5-8,5. Sinh khdi tii da djt td 0,749 den 0,807g/l.
Kit qud khdo sdt dieu ki^n dp 1\TC ban ehl dinh dudng dd xdc dinh dugc cdc nghi|m thde l/4N:l/4P:l/4Si (nito, phltpho vd silic bdng Yi nlng dd ehuan cda mdi hudng F/2) vd l/2N:l/2P:0Si (khdng bl sung silic) cho hi|u qud tich luy Upit ihn lugt djt 47% vd 60% hgng lugng khd.
Kit qud phdn tich thanh phin axit beo dugc este hda (Fatty Acid Methyl Ester, FAME) chdng Chaetoceros gracilis bdng sdc ki? khi GC-FID dd chi ra cdc axit b&
metyl este chinh d lodi nay Id C14:0, C16:0, C16:l. Trong do, ti 1$ axit b&) chd ylu phdn bl cd mach Mo hda hojlc 1 vd 2 Udn kit ddi vd ddi khdng qua 18 cdchon. Ti I5 axit bio bdo hda va khdng bao hda don noi ddi (SFA+MUFA) Id 92,43% (hon 70%) dugc nhgn dinh Id thich hgp cho chi sl citan cao.
Kit qud phdn Uch thanh phln axit bdo ehuyin este hda dS chi ra nhiSng mi dilm cda nguln Upit vi tao ndy dli vdi tieu chi chgn nguydn li|u cho chuyin hda biodiesel.
Kit qud cda cdng trinh nay la ludn cd cho cdc nghiSn cihi nang dp quy md nhan nudi vi tdo phuc vy phdt triln nhien U§u sinh hgc.
Tit khda: Biodiesel, Chaetoceros gracilis, lipit, khui tdo.
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