Penentuan suhu dan waktu terbaik Determinasi Kadar Logam Tembaga dalam gula pasir dengan Metode Microwave Digestion menggunakan Spektrofotometri Serapan Atom (SSA)

ABSTRAK

Tembaga (Cu) adalah bahan ikutan yang ditemukan dalam gula pasir. Tembaga berasal dari proses korosi logam tembaga pada rangkaian peralatan yang digunakan dalam pengolahan gula pasir. Penelitian ini bertujuan mengetahui performa analitik kurva standar dengan penentuan suhu dan waktu terbaik destruksi menggunakan microwave digestion, mengetahui performa analitik kurva adisi standar menggunakan suhu dan waktu terbaik destruksi untuk selanjutnya dilakukan uji kesesuaian.

Penelitian ini meliputi penentuan performa analitik untuk kurva standar meliputi linearitas, batas deteksi dan batas kuantitasi, sensitivitas, akurasi serta presisi, kemudian dilakukan pendestruksian sampel menggunakan destruksi basah menggunakan microwave digestion dengan variasi suhu sebesar 160 C, 180 C dan 200 C dan variasi waktu sebesar 15, 20 dan 25 menit. Penentuan performa analitik untuk kurva adisi standar yang selanjutnya dilakukan uji kesesuaian menggunakan uji-t.

Hasil penelitian didapatkan performa analitik untuk kurva standar tembaga meliputi r2 = 0,9993; LOD 0,0011 ppm dan LOQ 0,0036 ppm; sensitivitas 0,2; akurasi sebesar 100% , 101,25% ,99,16%, 99,375%, 100%; serta presisi 9,46%. Suhu dan waktu terbaik untuk destruksi gula pasir menggunakan microwave digestion sebesar 200 C selama 15 menit. Performa analitik untuk kurva adisi standar tembaga meliputi r2 = 0,9999; LOD 0,0012 ppm dan LOQ 0,004 ppm; sensitivitas 0,1729, akurasi sebesar 100%, 100% ,101,6%, 98,75%, 100%; serta presisi 5,38%. Uji t menunjukan bahwa t hitung lebih kecil daripada t tabel sehingga H0 diterima, artinya terdapat kesesuaian secara signifikan antara metode kurva standar dan metode kurva adisi standar.

ABSTRACT

Copper (Cu) is one of the trace element found in sugar. Copper (Cu) from copper corrosion processes in the circuit of the equipment used in processing sugar. This study aims to find out the analytical performance of the standard curve to determine the best temperature and time of ashing using microwave digestion, knowing the analytical performance using the standard addition curve and the best temperature for the ashing of the suitability test is then performed.

This research consist of determination of analytical performance for standard curves include linearity, limit of detection and limits of quantitation, sensitivity, accuracy and precision, then using wet destruction by microwave digestion with a variety of temperature that is 160 C, 180 C and 200 C and the variety of time that is 15, 20 and 25 minutes. After having the best temperature and time for wet ashing, the analytical performance for the standard addition curve and then performed using t-test.

The results for the analytical performance of a standard curve of copper (Cu) includes r2 = 0.9993; LOD 0.0011 ppm; LOQ 0.0036 ppm; sensitivity 0.2; accuracy of 100%, 101.25%, 99.16% , 99.375%, 100%, and precision of 9.46%. The best temperature and time for ashing using microwave digestion of sugar by 200 C for 15 minutes. Analytical performance of the standard addition curve for copper (Cu) includes r2 = 0.9999; LOD 0.0012 ppm; LOQ 0.004 ppm; sensitivity of 0.1729, an accuracy of 100%, 100%, 101.6%, 98.75%, 100%, and precision of 5.38%. T test shows that the t count is smaller than t table so that H0 is accepted, which mean that there is a significant accuracy between the standard curve method and the method of standard addition curve.