Removal of Chromium by Ion Exchange

8/13/2019 Removal of Chromium by Ion Exchange

1/15

Removal of Chromium by Ion Exchange

10/25/2013

Ben Green

Roxana Lopez


2/15

Removal of Chromium by Ion Exhan!e

"any impuri#ie$ an% #oxi $ub$#ane$ preven# &a#er from bein! u$eable' (hi$ i$

orre#e% &i#h #he #rea#men# of &a#er by removin! #he$e impuri#ie$ an% o#her un&an#e%

$ub$#ane$' (here are many #oxi me#al$ #ha# an on#amina#e &a#er' I# i$ impor#an# #o

on$i%er #he role of Chromium in &a#er$ %ue #o #hi$ rea$on' )i!h level$ an be #oxi #o

human$ an% #he environmen#'

Introduction

Background

Chromium an exi$# in $everal hemial form$ &i#h oxi%a#ion number be#&een 0

an% *' +,o#a$ an% -#a$i.a 2000' (here are #&o %ominan# form$ of Chromium #rivalen#

+Chromium III an% hexavalen# +Chromium I+- E4 2000' 6i#h #he ex#ra#e%

hromium i# an be u$e% #o ma.e me#al$ an% alloy$ +- E4 2000' (he #rivalen# ion i$

u$eful in human$ for #heir %ie# bu# #he hexavalen# ion an be harmful +- E4 2000'

Chromium III i$ le$$ #oxi #han Chromium I +Bazzi e# al' 2005' (herefore #he amoun#

allo&e% in %rin.in! &a#er mu$# be moni#ore% &i#h $#rin!en# re!ula#ion$ in or%er #o re%ue

#he a%ver$e effe#$'

Chromium i$ a$$oia#e% &i#h bo#h benefi#$ an% ne!a#ive$ &i#hin heal#h an%

$oie#y' )exavalen# hromium i$ la$$ifie% a$ an oxi%izin! a!en# +- E4 2010'

Beau$e hromium help$ #he human bo%y onver# !luo$e #o ener!y i#$ me%ial u$e$

vary &i%ely +- E4 2000' ,ey u$e$ of hromium inlu%e heal#hare an% me%iine$'

Cer#ain amoun#$ of Chromium are even nee$$ary for #he human bo%y #o perform ri!h#'

-ome pharmaeu#ial purpo$e$ inlu%e bloo% $u!ar level$ for people &i#h er#ain #ype$ of


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%iabe#e$' l$o $ome o#her me%ial u$e$ inlu%e %epre$$ion hear# me%ia#ion an% &ei!h#

lo$$'

Chromium al$o %i$play$ many u$eful purpo$e$ &i#h #he in%u$#rial an%

manufa#urin! $e#or$' Chromium i$ u$e% #o har%en $#eel u$eful for #ool$ an% $#eel

manufa#urin! e7uipmen# #ha# %eal$ &i#h ex#reme hea#$ an% o#her har% me#al$'

Chromium i$ a .ey in!re%ien# #o rea#in! $#ainle$$ $#eel +,rop$ho# an% 8oebrih 2010'

-#ainle$$ $#eel &i#h i#$ non9ru$#in! 7uali#y i$ %e$ire% in many re$i%en#ial an% ommerial

proper#ie$ for i#$ ex#ernal hara#eri$#i$' Chromium i$ al$o involve% in #he rea#ion of

many o#her alloy$' Chromium i$ al$o a%%e% #o er#ain #ype$ of !la$$ #o rea#e a olor

effe#'

Chromium Contamination

Chromium in &a#er a# #oo hi!h of onen#ra#ion$ oul% a%ver$ely affe# #he

&a#er:$ u$er$' 6a#er na#urally arrie$ only #rae$ amoun# of hromium ho&ever #he

variou$ in%u$#rie$ u$in! #he elemen# have inrea$e% #he hromium on#en# &i#hin &a#er'

"e#al $urfae refinerie$ or in%u$#rie$ rea#in! lea#her all on#ribu#e hromium #o #he af#er

$oure +- E4 2010' (oo muh onen#ra#ion of hexavalen# hromium ha$ le% #o

environmen#al i$$ue$ an% #hi$ i$ #he rea$on for #rea#men# of #he hromium'

Chromium i$ an i%en#ifie% arino!en' Chromium an au$e lun! aner in hi!h

enou!h onen#ra#ion$ +- E4 2010' Chromium an al$o au$e aller!i %erma#i#i$

&hen expo$e% for lon!er perio%$ of #ime +- E4 2000' (here are po$$ibly o#her heal#h

effe#$ #ha# hromium mi!h# have' Chromium * in par#iular an au$e perfora#ion of #he

na$al $ep#um a$#hma bronhi#i$ an% inflamma#ion of #he larynx an% liver +,o#a$ an%


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-#a$i.a 2000' Chromium an even be le#hal in onen#ra#ion$ of 0'1m!/! of bo%y

&ei!h# +Rihar% an% Bour! 1;;1' (he E4 an% o#her environmen#al a!enie$ are in

har!e of fi!urin! ou# any hazar% #ha# impuri#ie$ in &a#er may have a$ &ell a$ $e##in!

maximum level$ of onen#ra#ion for #he$e'

Chromium an be u$e% for ma.in! $#eel an% alloy$ an% for lea#her pre$erva#ion

ele#ropla#in! an% #ex#ile in%u$#ry amon! o#her u$e$ +- E4 2010' Chromium an

#herefore be foun% in in%u$#rial &a$#e&a#er$ &i#h onen#ra#ion$ be#&een 0'5 < 10

miro!ram$ per li#er +Barboo#i 2010' I# an al$o be na#urally foun% in #he ear#h=$

!roun%&a#er &i#h a #ypial onen#ra#ion le$$ #han 5 miro!ram$ per li#er +6orl% )eal#h

>r!aniza#ion 2003' (hi$ varie$ %epen%in! on #he re!ion bein! analyze% an% &he#her i#=$

!roun%&a#er or $ea&a#er' Curren#ly #he maximum on#amina#ion level +"CL i$ 100 ppb

+- E4' Le!i$la#ion re7uire$ #ha# #he onen#ra#ion of hromium be le$$ #han 0'5 m!/L

re!ar%le$$ of oxi%a#ion $#a#e +>nyanha e# al' 200?'

(Reyes-Gutierrez, 2009)


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(he $peie$ peren# v$ #he p) i$ $ho&n above' # a p) of * #here i$ a fra#ion of

eah $peie$ of Chromium I' $ #he p) inrea$e$ #he $peie$ of #he Chromium #ha# i$

%ominan# han!e$' 6hen #he p) i$ !rea#er #han *'@ Cr> Ai$ #he %ominan# $peie$ an% i$

almo$# #he only $peie$ pre$en# a# a p) of ?'5 an% !rea#er'

Ion-exchange

6a#er on#ain$ ion$ inlu%in! hromium ion$ &hih i$ #he fou$ of #hi$

labora#ory' (here are variou$ proe$$e$ #ha# an remove hromium ion$ inlu%in!

re%u#ion an% preipi#a#ion ion exhan!e an% a%$orp#ion +Ren!ara e# al 2001' Ion

exhan!e u$e$ re$in$' -al#$ u$e a fixe% number of anion$ an% a#ion$ in i#$ hemial

ompo$i#ion' Common #able $al# for example ha$ a one #o one propor#ion of $o%ium #o

hlori%e ion$ +Rohm an% )aa$ 200?' Ion exhan!e re$in$ are very $mall abou# 0'* mm

in %iame#er +Rohm an% )aa$ 200?' Ion exhan!e remove$ er#ain ion$ %epen%in! on

&he#her re$in a##ra#$ anion$ or a#ion$' -ome ion9exhan!er$ even have preferene$ for

er#ain ion$ over o#her$ %epen%in! on i#$ hemial ompo$i#ion' Ion exhan!e remove$

hromium ion$ by replain! i#$ anion &i#h an anion from #he re$in %e$i!ne% for #hi$

purpo$e +Rohm an% )aa$ 200?' $ &a#er pa$$e$ #he hromium ion$ are exhan!e% in

#he re$in for hlori%e$ or hy%roxi%e$ or o#her ion$ %epen%in! on #he #ype of re$in u$e%'

-ome a%van#a!e$ of ion exhan!e are #ha# ha$ reovery of me#al value $ele#ivi#y an%

le$$ $lu%!e volume +Ren!ara e# al' 2001'

Re$in$ oul% al$o be re!enera#e% #hrou!h a proe$$ alle% re!enera#ion'

6a$hin! #he olumn #o remove #he $u$pen%e% $oli%$ %oe$ #hi$' (he re!eneran# $olu#ion i$

#hen plae% in re$in +Rohm an% )aa$ 200?' Ion$ are #hen a##ahe% #o #hi$' (hi$ i$ #hen


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rin$e% ou# an% #he re$in i$ re!enera#e%' Eah re$in ha$ $ome#hin! alle% a $ele#ivi#y

oeffiien#' -ele#ivi#y oeffiien#$ are a mea$ure of #he pre%ile#ion of er#ain re$in$ for

er#ain ion$' (he$e oeffiien#$ are %epen%en# upon #he ra%iu$ &hen hy%ra#e% an% #he

ioni har!e of #he ion$' (he oeffiien# i$ al$o %epen%en# on #empera#ure pre$$ure an%

ompo$i#ion of bo#h pha$e$ +"arina e# al 1;;1' -ele#ivi#y oeffiien#$ apply only over

a $mall ran!e of onen#ra#ion$'

(here are #&o %ifferen# #ype$ of re$in overall #ha# an be u$e%' (hey are $ele#ive

re$in$ an% non$ele#ive re$in$' on$ele#ive re$in$ ab$orb many ion$ an% have a !rea#er

preferene for ion$ &i#h many har!e$ an% a# hi!her onen#ra#ion$ #han o#her ion$

+8>6ED' -ele#ive re$in$ are %e$i!ne% #o have a preferene for a er#ain #ype of ion

ba$e% on i#$ hemial ompo$i#ion +8>6ED' (he %ifferene be#&een $ele#ive an%

non$ele#ive i$ #ha# $ele#ive prefer$ a er#ain #ype of ion %e$pi#e #he onen#ra#ion$ of

o#her ion$ #ha# may have #he $ame har!e' (hi$ an be u$eful beau$e &hen #here are a

hi!h number of o#her impuri#ie$ #ha# aren=# e$$en#ial #o remove' (here are al$o ion$ #ha#

nee% #o be remove% #ha# are in a $maller onen#ra#ion #he $ele#ive re$in an be u$e% #o

ma.e $ure #ha# #he ion$ are remove% &i#h no problem'

a! "x#$anation

(hi$ lab %eal$ &i#h #he ion exhan!e for #he removal of Chromium' 6ha# #hi$

mean$ i$ a re$in &ill be a%%e% #o a Chromium $ample' (he purpo$e of #hi$ re$in i$ #o #a.e

#he ion$ from #he hromium a&ay an% allo& lean &a#er #o pa$$' (hi$ neu#ralize$ #he

$ample &hile har!in! #he re$in$' >ne #he re$in reahe$ i#$ apai#y #he re$in mu$# be

re!enera#e%' (hi$ i$ u$ually %one u$in! a re!enera#in! olumn' In #hi$ #he exhan!e%


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ion$ are rein#ro%ue% #o #he re$in #hrou!h a hi!hly onen#ra#e% brine &i#h a $#ron!

a##ra#ion for #he$e ex#ra ion$ a$ &ell' (he ion$ are #hen #a.en from #he re$in #o #hi$ ne&

$ub$#ane u$ually a #ype of $al# an% #he re$in$ are rehar!e% an% rea%y #o ion exhan!e

&i#h a on#amina#e% &a#er a!ain' If re!enera#ion &a$ no# applie% #he re$in$ &oul% no# be

a$ effe#ive an% may even even#ually no# &or. a# all'

6i#h all #he heal#h effe#$ of Chromium on#amina#ion an% a $#ri# "CL $e# by

#he E4 Chromium i$ a bi! priori#y #o remove from %rin.in! &a#er' I!norin! #he

hromium a%ver$e effe#$ oul% lea% #o an environmen#al %i$a$#er u$# a$ ea$y &hih i$

&hy i# i$ impera#ive for #he $#u%y an% #rea#men# of #hi$ elemen#' Chromium III an be

benefiial #o a per$on:$ heal#h' )o&ever #he hexavalen# ion of Chromium i$ %e#rimen#al'

Experimental Procedure

Batch %est

or #hi$ par# of #he experimen# $ix bo##le$ apable of hol%in! 100 mL of $ample

&ere u$e%' (he $#ar#in! onen#ra#ion of hromium in &a#er for #hi$ experimen# &a$ 200

F!/L or 0'2 m!/L' -#o. $olu#ion of Chromium u$e% &a$ 1000 F!/L' (o ob#ain #he

%e$ire% $#ar#in! onen#ra#ion 20 mL of hromium &a$ a%%e% in#o eah bo##le' (hi$ value

&a$ on$i$#en# for eah bo##le in or%er #o %e#ermine #he effe#ivene$$ of #he re$in on

hromium %epen%en# on varyin! amoun#$ of $ulfa#e' -ulfa#e &a$ varie% in #hi$ por#ion #o

%e#ermine #he effe# i# ha% on #he removal of hroma#e ba$e% on #he re$in u$e%'

Conen#ra#ion$ of $ulfa#e &ere 5 10 25 an% 50 m!/L' -ine #he $#o. $olu#ion of $ulfa#e

u$e% &a$ 500 m!/L #he amoun# a%%e% #o #heir re$pe#ive bo##le$ &ere 1 2 5 an% 10 mL'

Ba$e% on #he apai#y of #he -B92 re$in #he amoun# of re$in a%%e% #o eah bo##le &a$


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alula#e% #o be 0'02 !' (he remain%er of eah bo##le &a$ fille% u$in! %eionize% +8I

&a#er' (hi$ informa#ion i$ #abula#e% belo&'

Bottle Number

Blank Control 1 2 3 4DI Water(mL) 79 80 79 78 75 70

S4!2(mL) 1 0 1 2 5 10

Cr (mL) 20 20 20 20 20 20

"e#$n (%) 0 0&02 0&02 0&02 0&02 0&02

Table 1 Volume of Liuid! added

f#er a%%in! #he 8I &a#er $ulfa#e hromium an% re$in #he blan.H bo##le &a$

mea$ure% #o fin% #he preliminary onen#ra#ion$ ba$e% on #he volume$ a%%e%' Chromium

&a$ mea$ure% by a%%in! 10 mL of $ample in#o a vial &i#h a hromium9rea#an# rea!en#

pillo&' f#er allo&in! ? minu#e$ for #he olor #o fully %evelop #he vial &a$ plae% in#o

#he $pe#ropho#ome#er u$in! #he pre$e# hromium pro!ram #o ob#ain #he onen#ra#ion'

(he pro!ram &a$ able #o rea% a onen#ra#ion be#&een #he ran!e$ of 090'@00 m!/L'

-ulfa#e &a$ al$o mea$ure% by plain! 10 mL of $ample in#o a vial &i#h a $ulfa#e9rea#an#

rea!en# pillo&' f#er allo&in! 20 minu#e$ for #he olor #o fully %evelop #he vial &a$

plae% in#o #he $pe#ropho#ome#er u$in! #he pre$e# $ulfa#e pro!ram #o ob#ain #he

onen#ra#ion' (he pro!ram &a$ able #o rea% a onen#ra#ion be#&een #he ran!e$ of 09@0

m!/L' (he remain%er of #he bo##le$ &ere plae% in#o a $ha.er an% $ha.en for 2A hour$'

f#er #he allo##e% #ime #he onen#ra#ion$ of hromium an% $ulfa#e &ere mea$ure% u$in!

#he $ame me#ho% a$ before' In #he #e$#in! of Bo##le A #he $ulfa#e onen#ra#ion &a$

%ilu#e% u$in! 5 mL of $ample an% 5 mL of 8I &a#er $o a$ no# #o exee% #he ran!e'

Co$umn %est


9/15

3 L ba#h of $#o. $olu#ion &a$ rea#e% on#ainin! 0'AA? m!/L of Chromium

an% 200 m!/L of -ulfa#e' 1 m %iame#er olumn &a$ u$e% for #he #e$#' 20 mL of pre9

&e##e% re$in &a$ a%%e% #o #he olumn' $mall #ube &a$ in$er#e% in#o #he 3 L $ample of

$olu#ion an% ano#her #ube in$er#e% in#o #he olumn' $in! a pump #he &a#er &a$

#ran$ferre% from #he $olu#ion #o #he olumn' (he &a#er &a$ #hen expo$e% #o #he re$in an%

allo&e% #o %rip #hrou!h an% exi# #he olumn' I# &a$ impor#an# #o e7ualize #he flo& ou#

&i#h #he flo& in $o a$ #o no# overflo& or un%erflo& #he olumn bu# ra#her have

on#inuou$ flo&$ #hrou!hou#' (he exi#in! &a#er &a$ allo&e% #o fill a !ra%ua#e% ylin%er'

100 mL $ample$ of &a#er &ere #a.en af#er &a$#in! 300 mL' (he $amplin! proe$$ &a$

repea#e% for #he re$# of #he experimen#' (he $ample$ #a.en &ere #e$#e% aor%in! #o #he

)C) #e$#in! proe%ure$ for Chromium an% -ulfa#e' (he$e are #he $ame proe%ure$ a$

men#ione% in #he ba#h #e$#in! por#ion'

>ne #he re$in ha% been exhau$#e% i# &a$ nee$$ary #o re!enera#e #he re$in in

or%er #o ma.e i# u$eable one a!ain' (o %o #hi$ hi!hly onen#ra#e% brine &a$ u$e%' (he

brine &a$ run #hrou!h #he olumn in #he $ame manner a$ #he experimen#al por#ion above

bu# #he $ulfa#e an% hromium &a$ bein! remove% from #he re$in'

Re!ult! and "i!cu!!ion

Batch %est

(he re$ul#$ from #he ba#h #e$# are #abula#e% belo&'

Blan. Con#rol 1 2 3 A

->A92+m!/L 3? 0 3 3; *3 *5

Cr +m!/L 0'2A 0'0A 0'0A 0'0@ 0'0? 0'11

Table # Ending Concentration!


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$ #he #able above $ho&$ #he re$in &a$ effe#ive a# removin! bo#h #he -ulfa#e an%

Chromium from #he &a#er' (he blan. on#aine% 1 mL of -ulfa#e an% 20 mL of

Chromium' o re$in &a$ a%%e% in or%er #o have a ba$e onen#ra#ion' In #he on#rol only

re$in an% Chromium &ere a%%e%' (hi$ reveale% ho& #he re$in remove% #he Chromium

&i#hou# -ulfa#e hin%erin! i#' (he o#her four bo##le$ in #he ba#h #e$# ha% varyin! amoun#$

of -ulfa#e a%%e% #o #hem ran!in! from 1 mL #o 10 mL' $ #he re$ul#$ #able $ho&$ $ulfa#e

%oe$ have an effe# on ho& #he re$in remove$ #he on#aminan#' $ more -ulfa#e i$ a%%e%

le$$ Chromium i$ remove% from #he &a#er' In bo##le A no# enou!h Chromium &a$

remove% #o mee# #he "CL of 0'1 m!/L' >#her&i$e Chromium &a$ effe#ively remove%

%e$pi#e #he pre$ene of -ulfa#e in #he &a#er'

Co$umn %est

8urin! #he olumn #e$# #he re$in effe#ively remove% mo$# of #he hromium an%

$ulfa#e' (he re$in &a$ $o effe#ive in fa# #ha# #he brea.#hrou!h &a$ never a#ually

reahe%' l#hou!h #he olumn &a$ run in exe$$ of #he alula#e% #ime of 3'?2 hour$ an%

in exe$$ of #he alula#e% volume of 3 L #he apai#y &a$ never reahe%' (hi$ may be a

alula#ion error ho&ever #he $ame error$ oul% be foun% &hen ompare% #o variou$

!roup$ runnin! #he experimen#' (he $pe$ on #he re$in oul% have been on$erva#ive

value$ $o a$ no# #o overloa% #he re$in' !raph of #he umula#ive volume run #hrou!h #he

olumn v$' #he effluen# onen#ra#ion$ i$ $ho&n belo&'


11/15

&igure '- Cumu$atie %hrough#ut o$ume s* "++$uent Concentration

$ #he fi!ure $ho&$ #he onen#ra#ion of Chromium %i% no# vary !rea#ly %e$pi#e

#he amoun# of $olu#ion run #hrou!h #he olumn' (he experimen# &a$ #ermina#e% af#er

5*00 mL of $olu#ion &a$ u$e%' Ba$e% on #he re$ul#$ i# an be inferre% #ha# #he apai#y of

#he re$in &a$ no# exee%e% an% #herefore a brea.#hrou!h urve oul% no# be rea#e%' In

#heory #he brea.#hrou!h poin# $houl% have been reahe% !iven #he ini#ial 3 L of $olu#ion'

(hrou!hou# #he %ura#ion of #he experimen# $ulfa#e &a$ omple#ely remove%' (he volume

of re$in u$e% oul% han%le even more $olu#ion an% $#ill be effiien# a# removin! #he

on#aminan#$'

$ $ho&n in i!ure 1 #he onen#ra#ion of #he effluen# &a#er ran!e% from 0'01

m!/L #o 0'05 m!/L' ll of #he$e value$ are un%er #he ran!e of "CL for %rin.in! &a#er of

0'1 m!/L' (herefore #he re$in exelle% a# removin! bo#h #he -ulfa#e an% Chromium from

#he &a#er'

Conclu!ion!


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(he re$in u$e% &a$ very effe#ive in removin! #he on#aminan#$ from #he &a#er' In

#he ba#h #e$# #he $ame amoun# of re$in remove% on#aminan#$ &i#h varyin!

onen#ra#ion$' 6hen no -ulfa#e &a$ a%%e% #he Chromium &a$ re%ue% #o 0'0A m!/L

&ell &i#hin #he "CL' 6i#h #he a%%i#ion of $ulfa#e #he Chromium &a$ re%ue% belo& #he

"CL in all bu# one in$#ane' -ulfa#e &a$ al$o effe#ively remove% in mo$# of #he ba#he$'

l#hou!h -ulfa#e %oe$ have an effe# on #he re$in=$ effiieny #o remove Chromium #he

more $#rin!en# on#aminan# &a$ $#ill remove% #o &i#hin aep#able level$'

(he be!innin! onen#ra#ion$ from #he $olu#ion #ha# &a$ ma%e for #he olumn #e$#

&ere re%ue% #o a value &ell belo& #he "CL $e# by #he E4' In pra#ie #he re$in u$e%

&oul% be a !oo% re$in #o u$e for #he removal of Chromium' In fa# i# an be inferre% #ha#

&a#er &i#h a hi!her onen#ra#ion of Chromium or more &a#er &i#h #he $ame

onen#ra#ion$ oul% have been u$e%'

(he experimen# %emon$#ra#e% #he effe#ivene$$ of Ion9exhan!e in #he removal of

on#aminan#$ in &a#er' (hi$ proe%ure oul% be u$e% &i#h o#her on#aminan#$ a$ &ell $o

i# i$ a benefiial #ehnolo!y for ma.in! %rin.in! &a#er #ha# i$ &i#hin #he aep#able limi#$

$e# by #he E4'

References


13/15

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!i"e# $nternationa% &ourna% of $n"ustria% Chemistry 'o%.1, (o. 1

htt)#**+++.aca"emia.e"u*-2-1/*$nternationa%&ourna%of$n"ustria%ChemistryReco

veryofChromiumfromWasteTaningLiquorsbyMagnesium!i"e

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H6 :@, >Basic $nformation about Chromium in

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