Utilization of Ion-Exclusion Chromatography for Water Quality Monitoring in a Suburban River in Jakarta, Indonesia

Daisuke Kozaki,Takashi Ozaki,Kazuhiko Tanaka,Nobutake Nakatani,Masanobu Mori

doi:10.3390/w6071945

Abstract

We evaluated the use of ion-exclusion chromatographic systems for analyzing the behavior of inorganic ions (e.g., bicarbonate, sulfate, chloride, nitrate, phosphate, dissolved silicate, sodium, ammonium, potassium, magnesium, and calcium ions) in a suburban river located in Jakarta, Indonesia. Carbonate, phosphate, and silicate ion concentrations were determined using ion-exclusion chromatography (IEC) on a weakly acidic cation-exchange resin column (WCX) in the H+-form with water eluent. Other ions were identified by ion-exclusion/cation-exchange chromatography (IEC/CEC) on a WCX column with tartaric acid eluent. The use of IEC systems for water quality monitoring was advantageous for the following reasons: (1) the concentrations of analyte ions, except NO3− and silicate ions, increased from upstream to downstream; and (2) the speciation of inorganic nitrogen ions could be analyzed by single injection into the IEC/CEC. The IEC approach provided beneficial information for the construction of sewage treatment facilities in our study area. Results showed that (1) the analyte concentrations for samples obtained in the downstream area were higher than those in the upstream area owing to contamination by domestic sewage; (2) the concentrations of NO3− and NH4+ correlated with the concentration of dissolved oxygen; and (3) bicarbonate concentrations increased downstream, likely due to respiration of bacteria and dissolution of concrete under low-oxygen conditions.

Highlights

Water pollution and the eutrophication of lakes, rivers, and oceans have been caused by the influx of wastewater associated with rapid economic development, agriculture, and industry [1,2]
The proposed ion-exclusion chromatography (IEC) method can selectively separate and determine bicarbonate ion concentrations using a combination of weakly acidic cation-exchange resin column (WCX) and water eluent; this is possible owing primarily to the complete penetration of the bicarbonate ion in the cation-exchange resin phase [15,20]
We have demonstrated that IEC can successfully isolate the bicarbonate ion from salts of strong acids in approximately 10 min (Figure 3a)

Summary

Introduction

Water pollution and the eutrophication of lakes, rivers, and oceans have been caused by the influx of wastewater associated with rapid economic development, agriculture, and industry [1,2]. The present study focuses on the Ciliwung River (Figure 1) in Jakarta, Indonesia This river has become severely polluted by increasing urban populations (i.e., increasing organic components in human sewage) and in response to agricultural (e.g., through fertilizer and pesticide use in agricultural fields of rice, vegetables, and fruit) and industrial development (e.g., through introduction of organic components, several heavy metals, and other products produced by the food, beverage, textile, and rubber industries) [3,4,5,6,7,8,9,10]. To determine the degree of eutrophication of the river and secure its water resources, a sewage treatment system that can adequately treat wastewater should be developed; the development of such a system has been delayed, owing primarily to financial limitations

Methods

Results

Conclusion