Lub Chromatography Heating Challenge
Centrifugal partition chromatography systems rau kev cais cov khoom ntuj thiab tshuaj purification ua haujlwm nrog cov kuab tshuaj txaus uas txawv ntawm 2 mus rau 50 mL / min nyob ntawm qhov loj me thiab cov qauv thauj khoom. PFA rhaub tube yuav tsum tswj qhov kub ntawm qhov kub ntawm ± 0.3℃txawm tias qhov hloov pauv hloov pauv uas hloov cov cua sov rho tawm ntawm phab ntsa rhuab. Phab ntsa tuab ntawm PFA raj ncaj qha tswj hwm ob qho tib si tshuaj tiv thaiv kev ncaj ncees tiv thaiv cov kuab tshuaj hnyav sib xyaw (ethyl acetate, methanol, acetonitrile, dichloromethane) thiab cov thermal teb ceev kom ntws transients. Kev txheeb xyuas ntau los ntawm 18 chromatography kev teeb tsa qhia tau hais tias txhua qhov 0.5 hli nce hauv phab ntsa tuab ntxiv 12 mus rau 15 vib nas this rau lub sijhawm daws teeb meem tom qab 50% nce tus nqi nce.
Thermal Response Time Constant Dependence on Wall Thickness
Lub thermal teb ntawm lub raj PFA kom ntws hloov ua ntej- xaj dynamics nrog lub sij hawm tas li τ=(m × Cp) / (h × A), qhov m yog tube loj ib chav tsev ntev, Cp yog tshwj xeeb kub, h yog convective coefficient, thiab A yog tshav kub hloov chaw. Rau ib tug raug 6 hli txheej txoj kab uas hla PFA rhaub tube, 1.5 hli phab ntsa muaj 0.85 grams ntawm polymer ib cm ntawm ntev nrog thermal mass ntawm 1.02 J / cm·K. Phab ntsa 2.5 hli muaj 1.32 g / cm3 nrog thermal loj ntawm 1.58 J / cm·K. Ntawm tus nqi ntws ntawm 10 mL / min ua rau convective coefficient h ntawm 850 W / m²·K, 1.5mm phab ntsa nthuav tawm lub sijhawm tas li ntawm 4.2 vib nas this, thaum 2.5mm phab ntsa qhia 6.5 vib nas this. Thaum tus nqi ntws nce mus rau 30 mL / min (h=1400 W / m²·K), lub sij hawm poob mus rau 2.6 vib nas this thiab 4.0 vib nas this feem. 2.5mm phab ntsa tsis tu ncua teb 50% mus rau 60% qeeb dua li ntawm 1.5mm phab ntsa hla kev khiav hauj lwm ntau.
Temperature Deviation Thaum Flow Transients
Qhov sib txawv ntawm qhov kub thiab txias thaum lub sij hawm khiav tus nqi hloov pauv nrog lub sij hawm ntawm phab ntsa tas li thiab qhov hloov pauv ntawm qhov kub ntawm qhov rho tawm. Thaum tus nqi ntws nce los ntawm 50% ntawm lub tshuab hluav taws xob tas li, lub qhov hluav taws xob qhov hluav taws xob poob qis dua li cov kuab tshuaj txias dua tshem tawm cov cua sov los ntawm lub raj phab ntsa. Rau 1.5 hli phab ntsa, qhov siab tshaj plaws kub poob tom qab 20 mus rau 30 mL / min kauj ruam hloov yog 0.8 degree, nrog rov qab mus rau hauv 0.2℃ntawm setpoint hauv 9 vib nas this. Rau 2.5 hli phab ntsa nyob rau hauv zoo tib yam, qhov siab tshaj plaws poob yog 1.3℃nrog rov qab mus rau 0.2℃yuav tsum tau 16 vib nas this. Kev sib cais ntawm chromatography kav ntev li 30 txog 60 feeb tuaj yeem zam qhov kev sib txawv ntawm 1.3 degree, tab sis khiav yuav tsum muaj kev daws teeb meem nyob ze qhov chaw peaks ua kom pom lub ncov dav dav thaum kub sib txawv tshaj ± 0.5 degree. Rau cov kev siv siab - daws teeb meem no, phab ntsa 1.5mm yog qhov tsim nyog txawm tias txo cov tshuaj tiv thaiv cov thickness.
Chemical Barrier Adequacy rau Common Solvents
Qhov yuav tsum tau muaj tshuaj barrier thickness nyob ntawm qhov hnyav ntawm cov theem mobile. Cov txheej txheem hnyav sib xyaw ntawm methanol- dej (60:40) ntawm 40℃qhia tias tsis pom zoo permeation los ntawm 1.5mm PFA, nrog huab hwm coj poob qis dua 0.02 mg / cm² tom qab 2000 teev. Dichloromethane-methanol sib tov, feem ntau rau kev sib cais ntawm cov polar compound, o PFA ntau dua. Gravimetric swelling tests qhia dichloromethane uptake ntawm 1.2% hauv 1.5 hli PFA tom qab 1000 teev piv rau 0.7% hauv 2.5 hli PFA. Qhov o ua rau muaj qhov hloov pauv uas tuaj yeem xoob lub raj fittings, nrog 1.5mm phab ntsa qhia 0.10mm txheej txoj kab uas hla nce 0.06mm rau 2.5mm. Rau dichloromethane- muaj cov theem txawb, phab ntsa 2.0mm txog 2.2mm sawv cev qhov tsawg kawg nkaus rau kev ruaj ntseg ntev -lub sij hawm sealing. Ethyl acetate-hexane sib tov, nquag siv nyob rau hauv countercurrent chromatography, qhia tus cwj pwm o nyob nruab nrab qhov twg 1.8 hli phab ntsa txaus rau 3000-teev kev pab cuam lub neej.
Quantitative Trade-Tawm los ntawm Solvent System
| Mobile Phase Composition & Ua Haujlwm Kub | Yam tsawg kawg nkaus PFA Phab ntsa rau Chemical Barrier | Phab ntsa pom zoo rau Dynamic Teb (yog tias cov lus teb tseem ceeb) | Teem sij hawm tom qab 50% Flow nce (2mm vs. pom zoo) |
|---|---|---|---|
| Methanol- dej (80:20), 35 degree, qis polarity analytes | 1.5 hli | 1.5 hli | Tsis siv tau |
| Acetonitrile- dej (70:30), 50 degree, nruab nrab polarity | 1.5 hli | 1.5 hli | Ib yam li yam tsawg kawg nkaus |
| Ethyl acetate -methanol (75:25), 45 degree, khoom ntuj | 1.8mm ib | 1.8mm ib | 5 sec (2mm phab ntsa) vs . 8 sec (1.8mm) |
| Dichloromethane -methanol (90:10), 30 degree, hydrophobic compounds | 2.0 hli | 1.8mm (yog tias cov lus teb tseem ceeb, nrog lub neej luv dua) | 7 sec (2mm) vs . 5 sec (1.8 hli) |
| Tetrahydrofuran - dej (50:50), 55 degree, polymers | 2.2 hli | 2.0mm (nrog haum rov tsim) | 9 sec (2.2 hli) vs . 7 sec (2.0mm) |
Fitting Design Interacting nrog Phab Ntsa Thickness
Cov txiaj ntsig zoo ntawm cov phab ntsa nyias nyias yog pom tau tsuas yog thaum lub raj fittings tsis ua thermal dab dej uas tswj lub sij hawm tas li. Standard compression fittings nrog stainless hlau ferrules ntxiv qhov tseem ceeb thermal loj uas ncua qhov kub thiab txias teb tsis hais lub raj phab ntsa thickness. Rau cov ntawv thov chromatography xav tau cov lus teb ceev ceev, qhia PFA cov cua sov nrog PFA ferrule fittings uas phim lub raj phab ntsa tuab. Lub polymer ferrule muaj thermal huab hwm coj 15% ntawm qhov sib npaug stainless hlau ferrule, txo lub sijhawm tag nrho lub sijhawm tas li los ntawm 40% mus rau 50%. Rau 2.0 hli PFA raj nrog PFA ferrules, lub sij hawm teb zoo mus txog ntawm 1.5 hli raj nrog stainless hlau ferrules. Thaum retrofitting cua sov rau hauv cov tshuab chromatography uas twb muaj lawm nrog stainless hlau fittings, lub sij hawm teb yuav ntev dua li kev kwv yees los ntawm lub raj phab ntsa ib leeg.
Tubing Length thiab Preheat Section Tsim
Kev lag luam tawm - tawm ntawm phab ntsa tuab thiab cov lus teb dynamic tuaj yeem ua rau qee qhov txo qis los ntawm kev nthuav tawm cov kav dej kub ntev ua ntej kab sib cais. Ib ntu preheat ntev ua rau thaj tsam ntawm qhov chaw, txo qhov kub thiab txias qhov loj me thaum lub sij hawm ntws mus. Rau 2.5mm phab ntsa raj, nce rhuab ntev ntawm 100mm mus rau 250mm txo qhov siab tshaj plaws kub sib txawv tom qab 50% ntws nce los ntawm 1.3℃mus rau 0.9 degree, nce mus txog 1.5mm phab ntsa kev ua haujlwm. Lub txim yog nce siab poob (2.5 × ntev raj ntxiv 2.5 × siab poob) thiab loj dua lub hwj chim yuav tsum tau. Cov kws tsim qauv nyiam 2.5 hli phab ntsa rau qhov hnyav hnyav hnyav yuav tsum suav qhov ntev ntawm qhov yuav tsum tau ua kom ua tau raws li qhov ntsuas kub tau zoo dua li kev qhia cov phab ntsa nyias nyias uas cuam tshuam cov tshuaj tiv thaiv.
Specification Guide rau CPC System Design
Rau centrifugal partition chromatography hnyav cua sov, xaiv PFA phab ntsa tuab raws li qhov hnyav hnyav hnyav tshaj plaws nyob rau hauv theem mobile, ces txiav txim siab seb qhov tshwm sim thermal teb raws li qhov yuav tsum tau sib cais. Thaum qhov yuav tsum tau muaj cov tshuaj tiv thaiv kab mob ua rau cov lus teb tsis txaus ntseeg, xav txog peb txoj kev kho ua ntej xaiv cov phab ntsa nyias: txuas ntxiv rau ntu preheat, hloov cov hlau fittings nrog PFA ferrules, los yog nce tus nqi ntws los txo qhov cuam tshuam ntawm kev hloov pauv. Rau feem ntau cov khoom siv cais tawm siv cov khoom siv ethyl acetate -methanol lossis butanol- cov tshuab dej, 1.8mm txog 2.0mm PFA phab ntsa muab cov tshuaj lom neeg txaus thiab lub sijhawm teb rau cov txheej txheem gradient. Thaum qhia txog cov cua sov rau siab - kev daws teeb meem sib cais yuav tsum tau ± 0.2℃kev ruaj ntseg, xav kom tus neeg muag khoom muab cov kauj ruam- teb cov ntaub ntawv uas qhia txog qhov kub thiab txias rov qab lub sij hawm rau qhov tshwj xeeb raj txoj kab uas hla, phab ntsa thickness, thiab haum hom. Cov lus teb yuav tsum tau ntsuas ntawm lub qhov hluav taws xob lub raj, tsis yog ntawm lub tshuab hluav taws xob tswj qhov ntsuas qhov chaw, vim tias thermal lag ntawm sensor thiab qhov hluav taws xob txiav txim siab qhov tseeb ntawm kab inlet kub stability.
