Pengembangan dan Validasi Metode Analisis Kadar NH3-N di Limbah Industri Kayu Lapis Secara Spektrofotometri Sinar Tampak

Abstract

Air limbah industri kayu lapis umumnya mengandung senyawa amonia yang cukup tinggi. Metode fenat (SNI 06-6989.30-2005) digunakan dalam analisis amonia, akan tetapi memiliki kekurangan berupa batas linieritas hingga 0,6 mg/L NH3-N. Penentuan kadar amonia sering melakukan pengenceran yang dapat mengakibatkan penurunan akurasi dan lamanya proses analisis. Penelitian ini bertujuan mengembangkan metode fenat dan meningkatkan batas linieritas. Pengembangan dilakukan dengan mengubah panjang gelombang menjadi 660 nm dan waktu inkubasi 15 menit pada suhu 40°C. Metode yang dikembangkan diuji validitasnya, hasil validasi menunjukkan linieritas kurva kalibrasi dengan koefisien korelasi (r) sebesar 0,9992. Presisi pengujian pada rata-rata tiga titik konsentrasi menghasilkan %RSD 2,17% dan akurasi 100,10%. Deteksi limit (MDL) 0,0320 mg/L dengan batas kuantifikasi (LOQ) sebesar 0,0991 mg/L. Batas linearitas (LOL) menjadi 3,0 mg/L dan nilai Thit ruggedness 1,0566. Hasil validasi metode yang dikembangkan dapat dijadikan metode analisis rutin di PT. Unilab Perdana.

Plywood industry wastewater generally contains relatively high levels of ammonia compounds. The phenate method (SNI 06-6989.30-2005) is used in the analysis of ammonia, but it has a limitation with a linearity range up to 0.6 mg/L NH3-N. Determination of ammonia levels often dilutes which can result in a decrease in the accuracy and length of the analysis process. This research aims to develop the phenate method and increase the linearity range of the method. Development was carried out by changing the wavelength to 660 nm and the incubation time to 15 minutes at a temperature of 40°C. The developed method was validated, and the validation results showed the linearity of the calibration curve with a correlation coefficient (r) of 0.9992. The precision testing at the average of three concentration points resulted in a %RSD of 2.17% and an accuracy of 100.10%. The method detection limit (MDL) was 0.0320 mg/L with a limit of quantification (LOQ) of 0.0991 mg/L. The limit of linearity (LOL) became 3.0 mg/L and the Thit ruggedness value was 1.0566. The validation results of the developed method can be used as a routine analysis method at PT. Unilab Perdana