全 文 ：Received date:2012-07-11; Revised date:2012-10-02
Corresponding author:C． Srinivasakannan． Tel:+ 971-26075580，Fax:+ 971-26075200，E-mail:csrinivasakannan@ pi． ac． ae
Author introduction:K． Suresh Kumar Reddy (1981 －) ，male，Doctor，working as a research and teaching associate in The Petroleum Institute，
Abu Dhabi，UAE working on Bio mass conversion to activated carbons for natural gas processing．
English edition available online ScienceDirect (http:www ． sciencedirect． comsciencejournal18725805 )．
DOI:10． 1016 /S1872-5805(12)60020-1
Article ID: 1007-8827(2012)05-0344-08
A comparison of microstructure and adsorption characteristics
of activated carbons by CO2 and H3 PO4 activation from date palm pits
K． Suresh Kumar Reddy， Ahmed Al Shoaibi， C． Srinivasakannan
(Chemical Engineering Department，The Petroleum Institute，P． O． Box 2533，Abu Dhabi，UAE)
Abstract: This work attempts to compare the texture and the adsorption capacity of porous carbons prepared from date
palm pits using CO2 and H3PO4 activation． The activation conditions were chosen based on the optimized parameters re-
ported in the literature． The microstructure of the activated carbons was assessed based on nitrogen adsorption，SEM，
and FT-IR，while the adsorption capacity was estimated using methylene blue (MB)adsorption． CO2 activation resulted
in a microporous carbon with a yield of 44% and a BET surface area of 666 m2·g －1，H3PO4 activation resulted in a me-
soporous carbon with a yield of 14． 8% and a BET surface area of 725 m2·g －1 ． The average pore diameter of the activa-
ted carbons was estimated to be 1． 51 and 2． 91 nm for CO2 and H3PO4 activation respectively． The equilibrium adsorp-
tion isotherms for MB were fitted by the Langmuir and Freundlich models． The monolayer adsorption capacity of CO2
and H3PO4 activated carbons for MB from the Langmuir model were 110 and 345 mg·g
－1 respectively under the opti-
mized conditions． A highest MB adsorption capacity of 455 mg·g －1 was found for the H3PO4 activated carbon with a
highest BET surface area．
Keywords: Activated carbon;Physical activation;Chemical activation;Langmuir isotherm;Freundlich isotherm
CLC number: TQ 127． 1 + 1 Document code: A
1 Introduction
Porous carbons are well known and widely used
in industries for variety of separation applications．
The current interest on porous carbon for research
community，can be evidenced from the quantity of re-
search reported in open literature on porous carbons，
which accounts for nearly 30% of the overall research
in the field of carbon［1］． Generally the porous carbon
manufacturing methods are either based on physical
activation which are basically gasification reactions of
carbon with steam /CO2 /combination of both or based
on the chemical activation methods which include de-
hydrating agents such as phosphoric acid(H3PO4) ，
sodium hydroxide，potassium hydroxide，zinc chlo-
ride． The precursors for preparation of porous carbons
could be either coal or lingocellulosic material． Varie-
ty of biomass based precursors have been utilized for
preparation of porous carbons，of which the inherently
hard precursors such as coconut shells，palm shells，
almond shells，macademia nuts［2-4］ are popular choice
for physical activation methods，as the porous carbons
from these sources possess good physical strength and
desirable size that are suitable for packed bed adsorp-
tion application． However，chemical activation meth-
ods mostly produce powdered porous carbons from the
biomass precursors which include rubber wood，saw-
dust， coconut husk， bamboo， rice husk， apricot
shell，Jatropa hull et al［5-12］．
Among the available choice of impregnating
agents metal based activating agents such as KOH are
reported to be more suitable for coal based precur-
sors［13-14］，while H3PO4 and zinc chloride are widely
reported to be suitable impregnating agents for bio-
mass based lingocellulosic precursors． Compared with
zinc chloride，H3PO4 based porous carbons are com-
mercially preferred for applications in food，pharma-
ceutical and fine chemicals． Moreover，H3PO4 is eco-
friendly as it is non-polluting，easy to recover by sim-
ply solubilizing the salts of H3PO4 in water and can be
recycled back into the process． Hence the present
work attempts to utilize H3PO4 as the activating
agent． Although a large variety of precursors have
been tested to assess their suitability as a potential pre-
第 27 卷 第 5 期
2012 年 10 月
新 型 炭 材 料
NEW CARBON MATERIALS
Vol． 27 No． 5
Oct． 2012
cursor for manufacture of porous carbons，the work
related to utilization date palm pits as a precursor is
limited． Among the work reported in literature using
date palm pits［15-18］ as a precursor，only Girgis et
al．［19］ have utilized H3PO4 activation． However，the
optimum process conditions reported by Girgis et
al．［19］ were severe as compared with other biomass
based precursors［10，20］．
There are large quantities of waste date pits gen-
erated in the gulf region． However，the work on utili-
zation of date palm pits as a precursor for activated
carbon is lacking． In present work，such attempts are
made，using date palm pits as a precursor and CO2
and H3PO4 as activation agent． The prime objective
of present work is to compare the textural and adsorp-
tion characteristics of the porous carbon prepared at
the optimized conditions using both the activation
methods． The optimized conditions were determined
based on the recent optimized conditions reported in
literature［15］． The textural characteristics of the activa-
ted carbons were assessed based on the nitrogen ad-
sorption， Fourier Transform Infrared spectroscopy
(FT-IR) ，scanning electron microscopy (SEM)and
methylene blue (MB)adsorption as a popular adsor-
bate to select an adsorbent for macromolecule adsorp-
tion．
2 Experimental
2． 1 Preparation of porous carbon by CO2 activa-
tion
Date palm pits supplied by a local farm in Abu
Dhabi，U． A． E were utilized as the precursor． The
date palm pits were washed with deionized water to
remove foreign materials and dried in an oven at
105 ℃ for 24 h． The dried materials were ground and
sieved using a standard sieve to collect the precursor
with the size lower than 2 mm and were stored in a
desiccator for further use．
The dry date palm pit sample (10 g)was loaded
into a tubular furnace under N2 flow (120 mL /min)
and heated up to a carbonization temperature of
800 ℃ at a heating rate of 20 ℃ /min． The sample
was held at 800 ℃ for 1 h and cooled down to room
temperature under N2 flow ． The char yield was a-
round 28% ．
The char was placed in a tubular furnace under
N2 flow and heated at a heating rate of 20 ℃ /min to
the activation temperature of 971 ℃，then N2 flow
was switched to CO2 flow with a rate of 5． 1 mL /min
for 56 min for activation and finally CO2 flow was
switched back to N2 flow to terminate the activation．
The above conditions were chosen based on the repor-
ted optimum conditions for maximizing the yield and
BET surface area of date palm pits by Suresh et
al．［21］．
2． 2 Preparation of porous carbon by H3PO4 acti-
vation
The crushed and sieved date pits as detailed in
the above section was utilized as precursor for H3PO4
activation． 15 g of date dust was mixed with H3PO4
(60%) at an impregnation ratio (IR) (grams of
100% H3PO4·g
－1 ram of dried precursor)of 3． 1．
The mixture was kept under stirred condition for 5 h
using a magnetic paddle to ensure a complete soaking
of the H3PO4 into the precursor． After completion of
soaking of the acid into the precursor，the mixture
was dried in an oven at 105 ℃ until it was completely
dry and crisp． The dried powdery material was activa-
ted at 400 ℃ for 58 min without nitrogen flow in a
self-generated gas atmosphere． Upon completion of
the experiment，the carbonized samples were cooled
to the room temperature and washed repetitively with
distilled water to remove H3PO4 ． Repeated washing
was performed until the conductivity of filtrate was re-
duced to less than 50 μs． The washed product were
then dried in an oven at 105 ℃ for 12 h to ensure
complete dryness and the yield of activated carbon
was estimated based on grams of dry date palm pits
taken for activation． The above conditions were iden-
tified to be optimum for maximizing the yield and sur-
face area of the activated carbons．
2． 3 Characterization
The BET surface area and pore size distribution
were estimated using the standard nitrogen adsorption
isotherm obtained by an Autosorb 1-C adsorption ap-
paratus (Quanta Chrome Instruments，USA)． Prior
to analysis，the samples were first dried in an oven at
130 ℃ overnight and were quickly placed in the sam-
ple tube． The tube was then heated to 170 ℃ and was
evacuated for 4 h to a pressure less than 10-4 Torr．
The BET surface area was calculated from the iso-
therms using Brunauer-Emmett-Teller (BET)equa-
tion［22］． The Dubinin-Radushkevich (DR) model
was used to calculate the micropore volume［23］． The
total pore volume was calculated from the amount of
nitrogen adsorbed at a relative pressure of approxi-
mately 0． 99 to 1［24］
FT-IR spectra of various samples were recorded
on a Nicolet 740 FT-IR spectrometer at ambient con-
ditions using KBr as the diluent to identify the func-
tional groups in the activated carbons． The samples
were loaded into the sample holder and scanned in the
mid IR region of 100 to 4 000 cm-1 to generate the
spectra． A pellet made of nearly the same amount of
KBr was used as the background．
·543·
第 5 期 K． Suresh Kumar Reddy et al:A comparison of microstructure and adsorption characteristics of …
FEG-250 SEM instrument (FEI，Holland)was
employed at an accelerating voltage of 30 kV with a
2． 5 K magnification to estimate the surface pore
structure of the activated carbons．
2． 4 Adsorption experiments
Equilibrium adsorption of MB of analytical rea-
gent grade (Merck)was conducted a batch mode．
The MB solution for adsorption was prepared by dis-
solving MB in deionized water without pH adjust-
ment． A fixed amount (0． 1 g)of adsorbent was
taken in each conical flask (250 mL capacity)and
known concentration of MB (400， 800 and
1 200 mg /L)was added to the adsorbent． The coni-
cal flasks were kept in a shaker water bath at 30 ℃
and 200 revolutions per minute． The experiments
were continued for a period of 35 h to ensure an equi-
librium adsorption． After filtration the concentration
of solute in the solution was determined with a Hitachi
UV /visible spectrophotometer (U-2000 )． The
amount adsorbed at equilibrium，q e(mg·g
－1) ，was
calculated by
q e =
(C o － C e)V
W
where C o and C e are the initial and equilibrium con-
centrations (mg /L)respectively，V the volume of the
solution (L) and W the weight of dried carbon
(mg)．
3 Results and discussion
The activated carbon samples were prepared at
the optimized conditions for maximizing their yields
and the BET surface areas in the earlier reports for the
date palm pits． The optimized conditions for the CO2
activation are an activation temperature of 971 ℃，an
activation time of 56 min and a CO2 flow rate of
5． 1 mL /min． The optimized conditions for H3PO4
activation are an activation temperature of 400 ℃，an
impregnation ratio of 3． 1 and an activation time of
58 min． The CO2 activation process results in an acti-
vated carbon with a yield and a BET surface area of
14． 8% and 666 m2·g －1，respectively，while those
values for H3PO4 activation are 44% and 725 m
2·g －1
respectively． However，the process conditions corre-
sponding to a maximum BET surface area are differ-
ent from the optimized conditions．
As can be seen from the optimum conditions，the
CO2 activation demands a high activation tempera-
ture，while the H3PO4 activation demands a low acti-
vation temperature． The natures of reactions in the
two process were different and hence the optimum
conditions were different． In the case of CO2 activa-
tion，the gasification reactions of carbon with CO2
leads to a generation of pores，while in the case of
H3PO4 activation the reactions of lignocellulose with
the H3PO4 are different，which include first break of
hemicellulose and lignin，then hydrolysis of the gly-
cosidic linkages in the lignocellulose and split of aryl
ether bond in lignin，and finally dehydration，degra-
dation and condensation［25］． Although the yield，sur-
face area and the activation conditions are favorable
for the H3PO4 activation process，it involves a labori-
ous recovery and regeneration step． An activation
temperature above 500 ℃ was reported to decrease
acid recovery，owing to a possible sublimation of the
salts of H3PO4 at temperatures higher than 500 ℃
［10］．
The high yield is attributed to the dehydrogenation re-
actions that inhibit the formation of tar and reduce the
production of other volatile products．
3． 1 Textural characteristics of CO2 and H3PO4
activated carbons
Characterization of pore structure of an adsorbent
is essential，for which inert gas adsorption［26］ is a
good option． Fig． 1 shows the N2 adsorption /desorp-
tion isotherm at 77 K for the CO2 and H3PO4 activated
carbons． The CO2 activated carbon shows a sharp in-
crease in the adsorption volume up to a p /p0 of 0． 1
and remains constant beyond． This type of isotherm is
characteristic of microporous material and are classi-
fied as Type-I adsorption isotherm under the IUPAC
classification． The desorption doesn’t show a signifi-
cant deviation from the adsorption isotherm，indica-
ting cylindrical pores without the presence of slit type
or bottle neck type of pores． This type of adsorption
isotherm is also indicative of only monolayer adsorp-
tion［27］． There is a sharp increase in the adsorption
volume up to a p /p0 of 0． 1 for the H3PO4 activated
carbon，similar to the CO2 activated carbon，which
was attributed to the presence of micropores． Howev-
er，a progressive increase in volume adsorbed in the
Fig． 1 Adsorption /desorption isotherms of N2 at 77 K for the CO2
and H3PO4 activated carbons derived from date palm pits
·643·
新 型 炭 材 料 第 27 卷
entire range of p /p0 could be attributed to the meso-
porous nature of the porous carbon． In addition，de-
sorption isotherm exhibits hysteresis loops at a relative
pressure in excess of 0． 4，which are characteristic of
Type-IV isotherm． A steep increase in the slope at a
high relative pressure (p /p0 ＞ 0． 8-1) ，could be at-
tributed to a capillary condensation in mesopores．
The relevant data from adsorption isotherm is
compiled in Table 1． A comparison of textural char-
acteristics clearly indicates the pore volumes and aver-
age pore size are higher and the proportion of micro-
pores is lower for the H3PO4 activation than those for
the CO2 activated carbon． This clearly indicates that
the CO2 activated carbon is suitable for the adsorption
of small molecules typically for the gas phase adsorp-
tion，while the H3PO4 activated carbon is suitable for
the adsorption of macromolecules typically for liquid
phase adsorption． The ability of the H3PO4 to produce
mesoporous carbon with a high surface area has been
reported in literature［10］with an average pore diam-
eter in excess of 3． 2 nm，which agrees well with the
present work． Table 1 also provides the process con-
ditions that are favorable for the maximum of BET
surface area，with an activation temperature and an
activation time higher than the optimized conditions．
The BET surface area of 980 and 952 m2·g －1 are ob-
tained under conditions for maximum BET surface ar-
ea． However，the yield was lower under these condi-
tions than the optimum conditions reported．
Table 1 Physical properties of the activated carbons derived from date palm pits with different activation procedures
Activation t /℃ t /min SBET / (m2·g － 1) v t / cm3·g － 1 vmicro /v t DP /nm# Yield w /%
Physical (CO2) 971 56 666 0． 41 0． 92 1． 56 14． 8
Chemical (H3PO4) 400 58 725 1． 26 0． 31 2． 90 44． 0
Physical (CO2)* 1063 68 980 0． 61 0． 93 1． 57 9． 5
Chemical (H3PO4)* 450 75 952 1． 38 0． 36 2． 91 41． 0
Note:Maximum (* ) ，Optimized ()conditions，# Dubinin-Radushkevich method
The surface morphology of activated carbon pro-
duced using both methods are shown in the SEM mi-
crograph Fig． 2)． The pores on the surface of the car-
bon by CO2 activation are uniform in the size range of
meso to macro porous region． These pores are the ex-
terior pores that serve as the main channels that connect
to the micropores on the inner surface of the carbon．
The H3PO4 activated carbon shows relatively large，
non-uniform and abundant pores on the surface of acti-
vated carbon． The large pore size of H3PO4 activated
samples as compared with the CO2 activated ones is in
accordance with the estimated pore sizes from nitrogen
adsorption．
Fig． 2 SEM images of (a)CO2 and (b)H3PO4 activated carbons generated at the optimized conditions
The FT-IR spectra of precursor and activated car-
bons by the two types of activation are presented in
Fig． 3． The IR bands of these samples are different，
with the precursor closely matching with the IR spec-
trum reported in literature［28-29］． The IR spectrum of
the precursor shows the presence of functional groups
such as alkene，ester，aromatic，ketone，alcohol，hy-
droxyl，ether and carboxyl． This is in accordance
with the date palm pits composed of cellulose，hemi-
cellulose and lignin． The H3PO4 activated carbon
shows IR bands around 3 400-3 600 cm-1 which are at-
tributed to the -OH vibration stretching of hydroxyl
groups involved in hydrogen bonding possibly due to
adsorbed water［16］． The bands appearing at
1 640 cm －1 are ascribed to olefin functional groups
and the one at 1 150 cm －1 to the stretching vibration
·743·
第 5 期 K． Suresh Kumar Reddy et al:A comparison of microstructure and adsorption characteristics of …
of aromatic ring (methoxy-O-CH3)
［15］． The peaks
observed in the raw date pits have disappeared，owing
to the transformation of bond due to the interaction of
the precursor with H3PO4 ． The CO2 activated carbon
shows hydroxyl peaks (at 3 400 cm-1)that are intense
and the disappearance of certain bands as compared
with the H3PO4 activated one is generally attributed to
the increase in aromaticity of the material［15］． The
presence of -OH groups imparts negative charge to the
activated carbon surface． The large differences in sur-
face functional groups between the two activated car-
bons are visible． Therefore，it is possible to prepare
porous carbons suitable for specific application by uti-
lizing different activation methods．
Fig． 3 FT-IR images of (a)CO2 and (b)H3PO4
activated carbons generated at the optimized conditions
3． 2 Adsorption isotherms
The adsorption of organics onto activated carbon
is generally understood to be dependent on the pore
structure and surface chemical properties of activated
carbon and properties of adsorbate． The dye adsorp-
tion test helps to determine the capacity of carbon to
adsorb molecules of a particular size． The adsorption
isotherms for activated carbons from the CO2 activa-
tion and the H3PO4 activation were fitted by the Lang-
muir and Freundlich models［30-31］． The estimated
model parameters along with suitability of model to
represent experimental data are listed in Table 2 and
adsorption isotherms shown in Fig． 4 and 5． The
adsorption on the CO2 activated carbon can be best
Table 2 Parameters of Langmuir and Freundlich
equations and standard deviations for the adsorption
of MB on various activated carbons at 30 ℃
Adsorbent
Langmuir equation
qm /mg·g － 1 Δq e /%
Freundlich equation
1 /n KF Δq e /%
AC (CO2) 109． 9 0． 49 0． 185 28． 1 1． 30
AC (H3PO4) 344． 8 1． 50 0． 058 232． 2 0． 44
AC (H3PO4)* 455． 0 1． 61 0． 152 8 150． 0 0． 51
Note:AC denoted as activated carbon
Fig． 4 Adsorption isotherms of MB at 30 ℃
on the CO2 activated carbon from date palm pits
Fig． 5 Adsorption isotherms of MB at 30 ℃
on the H3PO4 activated carbon from date palm pits
represented by the Langmuir model and the adsorption
on H3PO4activated carbon by the Freundlich model．
The Langmuir equation is intended for a homogeneous
surface，while Freundlich equation is suitable for a
highly heterogeneous surface［32］，which often gives a
good representation of adsorption data over a restrict-
ed range of concentrations．
The monolayer adsorption capacity from the
Langmuir isotherm is a popular index to compare the
maximum adsorption capacity of different adsorbents．
The monolayer adsorption (qm)capacity for the CO2
activated carbon was estimated to be 110 mg·g －1
while that for H3PO4 activated one was estimated to
be 345 mg·g －1 ． The low adsorption capacity of the
MB by the CO2 activated carbon can be attributed to
the small average pore size as listed in Table 1． The
micro pore volume of the CO2 activated carbon con-
tributes to nearly 93%，which are pores of size lower
than 2 nm． The MB molecule has a minimum molec-
ular cross-section of about 0． 8 nm and cannot enter
the pores with sizes less than 1． 3 nm［33-34］． Since the
quantity of pores in excess of 1． 3 nm is minimal for
·843·
新 型 炭 材 料 第 27 卷
the CO2 activated samples，the maximum adsorption
capacity of MB is relatively low ． On the other hand
the H3PO4 activated carbon has an average pore diam-
eter of 2． 9 nm with a mesopore volume around 70%，
large enough to accommodate MB． Therefore，the
adsorption capacity of the MB is high for the H3PO4
activated carbon as shown in Table 2． Table 3 com-
piles the MB adsorption capacity of activated carbon
prepared from different precursors by H3PO4 activa-
tion［35-41］． The MB adsorption capacity of the porous
carbon prepared in the present work，is significantly
higher than those reported in literatures．
Table 3 Reported MB adsorption capacities
of activated carbons in literatures
Precursors Activating agents q e / mg·g － 1
Coffee grounds［35］ H3PO4 181
Cotton stalk ［36］ H3PO4 245
Peach stone［37］ H3PO4 412
Rice straw ［38］ H3PO4 110
Fibrous rice straws［39］ H3PO4 107
Camellia Oleifera shell［40］ H3PO4 330
Rice straw ［41］ KOH 529
4 Conclusions
A comparison of the textural and adsorption char-
acteristics of the activated carbon from date palm pits
by the CO2 and the H3PO4 activation leads to the
following findings:
An activated carbon by the CO2 activation under
the optimum conditions has a BET surface area of
666 m2·g －1 and a yield of 14． 8%，while that by the
H3PO4 activation has a BET surface area of
725 m2·g －1 and a yield of 41% ． However，the max-
imum BET surface area for both activation methods is
obtained under different activation conditions．
The CO2 activation generated a highly micro-
porous carbon (92%)with a Type-I isotherm，while
the H3PO4 activation generated a mesoporous one
(70%)with a Type-IV isotherm，the pore volumes
are 0． 41 and 1． 26 cm3·g －1 respectively． The aver-
age pore size of the activated carbons is 2． 9 and
1． 56 nm for H3PO4 activation and CO2 activation，re-
spectively．
The FT-IR spectra indicated significant variation
in the surface functional groups are quite different for
the H3PO4 activated and CO2 activated carbons．
The monolayer adsorption capacity of the activa-
ted carbon for MB was estimated to be 110 and
345 mg·g －1 for CO2 activated carbon and H3PO4 acti-
vated one． A maximum MB adsorption capacity of
455 mg·g －1 corresponds to a maximum surface area
for the H3PO4 based carbon．
Acknowledgments
The authors wish to acknowledge the financial
support from the Petroleum Institute for giving an op-
portunity to work on activated carbon for gas process-
ing research．
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·053·
新 型 炭 材 料 第 27 卷
海枣核 CO2活化和磷酸活化制备活性炭
及其结构、吸附性能
K． Suresh Kumar Reddy， Ahmed Al Shoaibi， C． Srinivasakannan
(Chemical Engineering Department，The Petroleum Institute，P． O． Box 2533，Abu Dhabi，UAE)
摘 要: 由于具有很大的吸附容量，多孔炭材料是优良的吸附剂。笔者试图比较海枣核分别经 CO2 活化和磷酸
活化所制活性炭的结构和吸附性能。活化过程和工艺条件对炭的物理化学性质影响较大，根据文献报道的结果选
取了优化的工艺参数。基于氮气吸附等温线、SEM、FT-IR等分析结果，评估了活性炭的结构特征，吸附性能则由亚
甲蓝吸附值表示。CO2 活化得到了微孔活性炭，产率为 44%、BET 比表面积是 666 m
2·g －1;磷酸活化得到了产率
为 14． 8%的中孔活性炭，BET 比表面积为 725 m2·g －1。CO2 活化活性炭的平均孔径是 1． 51 nm，磷酸活化活性炭
的则为 2． 91 nm。活性炭的亚甲蓝吸附等温线分别用 Langmuir等温线和 Freundlich等温线进行了验证，在优化工
艺条件下制备的 CO2 活化炭和磷酸活化炭的亚甲蓝 w 单分子吸附容量分别为 110 mg·g
－1和 345 mg·g －1。然而，
磷酸活化产生的亚甲蓝吸附值最高达 455 mg·g －1。
关键词: 活性炭;物理活化;化学活化;Langmuir等温线;Freundlich等温线
通讯作者:C． Srinivasakannan． Tel:+ 971-26075580，Fax:+ 971-26075200，E-mail:csrinivasakannan@ pi． ac． ae
作者介绍:K． Suresh Kumar Reddy (1981 －) ，博士，主要从事生活转化制备活性炭的研究
．
株洲晨昕中高频设备有限公司
高温石墨化炉
●用于 3000℃以内的超高温炉，用于各种炭材料的碳化和石墨化实验、
中试生产碳素材料的碳化，石墨化;炭纤维灯丝的定型石墨化及其它可
在碳环境下烧结和熔炼的材料。
●常用于处理电池材料、石墨改性，制备高模量纤维等。
使用温度:最高 3000℃，常用 2800℃
恒温区:立式 D200 × 350mm;卧式 D110 × 900mm
温度均匀度:≤ ± 15℃;控温精度:± 1℃
工作气氛:真空置换 Ar2、N2保护(微正压)
温度测量:红外光学测温，测温范围 1000 ～ 3000℃;测温精度:0． 3%
联系电话:0731-28633975
技术支持:13973351517
网 址:www． chenxinzz． com
系列高温石墨化炉型号及性能参数
高温石墨化炉 单位 KGPS-60 KGPS-100 KGPS-160 KGPS-200 KGPS-250
坩埚有效容积
(直径 ×高)
mm D50 × 300 D200 × 350 D300 × 500 D400 × 750 D500 × 1000
中频电源功率 kW 60 100 160 200 250
中频电源频率 Hz 8000 4000 4000 2500 2000
最高工作温度 ℃ 3200 3000 3000 3000 2600
极限真空度 Pa 1． 2 × 10 －1 1． 2 × 10 －1 1． 2 × 10 －1 1． 2 × 10 －1 1． 2 × 10 －1
压升率 Pa /h 2 2 2 2 2
恒温区温差 ℃ ±10 ± 10 ± 10 ± 15 ± 15
·153·
第 5 期 K． Suresh Kumar Reddy et al:A comparison of microstructure and adsorption characteristics of …