8/13/2019 Removal of Chromium by Ion Exchange
1/15
Removal of Chromium by Ion Exchange
10/25/2013
Ben Green
Roxana Lopez
8/13/2019 Removal of Chromium by Ion Exchange
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
8/13/2019 Removal of Chromium by Ion Exchange
3/15
%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$$ibly o#her heal#h
effe#$ #ha# hromium mi!h# have' Chromium * in par#iular an au$e perfora#ion of #he
na$al $ep#um a$#hma bronhi#i$ an% inflamma#ion of #he larynx an% liver +,o#a$ an%
8/13/2019 Removal of Chromium by Ion Exchange
4/15
-#a$i.a 2000' Chromium an even be le#hal in onen#ra#ion$ of 0'1m!/! of bo%y
&ei!h# +Rihar% an% Bour! 1;;1' (he E4 an% o#her environmen#al a!enie$ are in
har!e of fi!urin! ou# any hazar% #ha# impuri#ie$ in &a#er may have a$ &ell a$ $e##in!
maximum level$ of onen#ra#ion for #he$e'
Chromium an be u$e% for ma.in! $#eel an% alloy$ an% for lea#her pre$erva#ion
ele#ropla#in! an% #ex#ile in%u$#ry amon! o#her u$e$ +- E4 2010' Chromium an
#herefore be foun% in in%u$#rial &a$#e&a#er$ &i#h onen#ra#ion$ be#&een 0'5 < 10
miro!ram$ per li#er +Barboo#i 2010' I# an al$o be na#urally foun% in #he ear#h=$
!roun%&a#er &i#h a #ypial onen#ra#ion le$$ #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)
8/13/2019 Removal of Chromium by Ion Exchange
5/15
(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
8/13/2019 Removal of Chromium by Ion Exchange
6/15
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$$' (hi$ neu#ralize$ #he
$ample &hile har!in! #he re$in$' >ne #he re$in reahe$ i#$ apai#y #he re$in mu$# be
re!enera#e%' (hi$ i$ u$ually %one u$in! a re!enera#in! olumn' In #hi$ #he exhan!e%
8/13/2019 Removal of Chromium by Ion Exchange
7/15
ion$ are rein#ro%ue% #o #he re$in #hrou!h a hi!hly onen#ra#e% brine &i#h a $#ron!
a##ra#ion for #he$e ex#ra ion$ a$ &ell' (he ion$ are #hen #a.en from #he re$in #o #hi$ ne&
$ub$#ane u$ually a #ype of $al# an% #he re$in$ are rehar!e% an% rea%y #o ion exhan!e
&i#h a on#amina#e% &a#er a!ain' If re!enera#ion &a$ no# applie% #he re$in$ &oul% no# be
a$ effe#ive an% may even even#ually no# &or. a# all'
6i#h all #he heal#h effe#$ of Chromium on#amina#ion an% a $#ri# "CL $e# by
#he E4 Chromium i$ a bi! priori#y #o remove from %rin.in! &a#er' I!norin! #he
hromium a%ver$e effe#$ oul% lea% #o an environmen#al %i$a$#er u$# a$ ea$y &hih i$
&hy i# i$ impera#ive for #he $#u%y an% #rea#men# of #hi$ elemen#' Chromium III an be
benefiial #o a per$on:$ heal#h' )o&ever #he hexavalen# ion of Chromium i$ %e#rimen#al'
Experimental Procedure
Batch %est
or #hi$ par# of #he experimen# $ix bo##le$ apable of hol%in! 100 mL of $ample
&ere u$e%' (he $#ar#in! onen#ra#ion of hromium in &a#er for #hi$ experimen# &a$ 200
F!/L or 0'2 m!/L' -#o. $olu#ion of Chromium u$e% &a$ 1000 F!/L' (o ob#ain #he
%e$ire% $#ar#in! onen#ra#ion 20 mL of hromium &a$ a%%e% in#o eah bo##le' (hi$ value
&a$ on$i$#en# for eah bo##le in or%er #o %e#ermine #he effe#ivene$$ 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$in a%%e% #o eah bo##le &a$
8/13/2019 Removal of Chromium by Ion Exchange
8/15
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
8/13/2019 Removal of Chromium by Ion Exchange
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!
8/13/2019 Removal of Chromium by Ion Exchange
10/15
$ #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&'
8/13/2019 Removal of Chromium by Ion Exchange
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!
8/13/2019 Removal of Chromium by Ion Exchange
12/15
(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
8/13/2019 Removal of Chromium by Ion Exchange
13/15
Barbooti, M., 2010, Recovery of Chromium from Waste Tanning Liquors by Magnesium
!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
Bai, ., 3reu, B., Wuo4i%a, &., Maqbou%, ., 2005. 6e)aration an" "etermination of
Cr7$$$8 an" Cr7'$8 +ith cation9e!change chromatogra)hy an" atomic absor)tion
s)ectrosco)y. &ourna% of Chemica% :"ucation, /2, 'o%. /2, (o. ;
8/13/2019 Removal of Chromium by Ion Exchange
14/15
Rengara, 6., eon, 3., D Moon, 6. 720018. Remova% of chromium from +ater an"
+aste+ater by ion e!change resins.Journal of Hazardous Materials, 8771J;8, 2;92/.
"oi#htt)#**"!."oi.org*10.101*60;09;/-7018002-19
Reyes9Eutierre, Laaro, et a%. )r. 200-. >Chemica% 6)ecies of Chromatite of an
$n"ustria% Lan"fi%% in the Leon 'a%%ey, Euanauato, Me!ico? SciEL. Revista me!icana
"e ciencias geo%oicas, Web. 1- (ov. 201;
Nhtt)#**+++.scie%o.org.m!*scie%o.)h)A)i" /200-00010000-Dscri)tsciartte!tO.
Richar", I., Bourg, ., 1--1. queous Eeochemistry of Chromium# revie+. Water
Resources, 'o%. 25, (o. , )). /09/1.
Rohm an" Kaas, 6e) 200/. >$on :!change for Chromium Com)oun"s.? Web. 1-
(ov.201;.Nhtt)#**+++.e)a.gov*ttn*at+*h%thef*chromium.htm%O.
H6 :@, 6e) 2010. To!ico%ogica% revie+ of Ke!ava%ent chromium. Web. 1/ (ov. 201;
+++.e)a.gov*iris
H6 :@,
8/13/2019 Removal of Chromium by Ion Exchange
15/15
H6 :@, >Basic $nformation about Chromium in
Top Related