PENGGUNAAN INTERNAL STANDAR NITROBENZENA UNTUK PENENTUAN KUANTITATIF BTEX DALAM KONDENSAT GAS ALAM DENGAN KROMATOGRAFI GAS
Abstrak: This research has
been carried out the selection of three types of compounds to be used as an
Internal Standard (ISTD) on the quantitative determination of BTEX in the
natural gas condensate, they are pyridine and nitrobenzene marpholine that have
the similar chemical compound with the analyte (aromatic hydrocarbons). The
ISTD selection is done by mixing ISTD with natural gas condensate samples into
the solvent carbon disulfide (CS 2 ), and then 1μl injected into the Gas
Chromatography (GC) to know the column elution or separation of the mixture.
From the results of research that have been conducted on three types compounds,
it was found that pyridine can not be used as ISTD because it can not be
eluted, as well marpholine CS 2 reacts rapidly with solvent to form a white
solid before it is injected. While nitrobenzene mixtures eluted at a retention
time of + 76.953 min after o-xylene. Next step is preparation ISTD
nitrobenzene, BTEX standard solution and sample into the solvent CS2, based on
the dilution of wight base using analytical balance, to obtain a concentration
of ISTD in the same amount that is 4 g/g on BTEX
standard solution and the sample. BTEX standard solution prepared with 6
variations concentrations of K 1 to K 6 that reflect the concentration of BTEX
in the sample. From BTEX standard solution K1 to K6, all of them are
injected into the gas chromatograph, then it is made the multi-level
calibration curve by comparing the area ratios of analyte/ISTD vs concentration
ratio of analyte/ISTD. The Quantitative determination of BTEX in the natural
gas condensate is done by interpolating the regression equation obtained from
the multi level calibration curve linearity for each aromatic BTEX compounds.
The correlation coefficient (r) is obtained varies the 0.9993 to 0.9997. Other
parameters such as precision and accuracy were also evaluated. So from this
study is obtained BTEX concentrations in natural gas condensate with the ISTD
nitrobenzene. They are Benzene is 3.0605 % wt; Toluene is 7.0053 % wt;
Ethylbenzene is 0.8568 % wt, and ortho-meta-para-Xylenes are 2.8873 % wt;
0.8704 % wt ; 0.8026% wt.
Keywords: ISTD, nitrobenzene,
pyridine, marpholine, CS2, preparation, natural gas condensate, BTEX, gas chromatography
Penulis: Rohmat Hidayat, Subur
P Pasaribu, Chairul Saleh
Kode Jurnal: jpkimiadd150413
