This research was done to analyze the effect of radiation dose of electron beam radiation to the concentration reduction of naphtol soga dyes waste which result from process coloration of batik cloth pH = 5,5. Irradiation had been done to napthol soga waste which result from process coloration in Plentong batik industry, at various initial pH 3, 5, 7, 9, 11 and various radiation dose 15, 25, and 35 kGy. The changes of concentration were analyzed by Hitachi U-2000 spectrophotometer UV-Vis, which measured UV-Vis absorption by waste solution at 319 nm and 382 nm wavelength and HPLC was used to get degradation product of radiation.
The results showed that on radiation dose range 15 kGy to 35 kGy, the higher radiation dose absorbed by naphtol soga waste solution, the higher reduction of naphtol soga waste concentration. One of radiolysis products of naphtol soga waste solution was oxalate acid with concentration 0,017 % to 0,020 % on radiation dose range 15 kGy to 35 kGy. The higher radiation dose, the lower BOD and COD contents of naphtol saga waste solution. The optimum radiation dose was 35 kGy which reduced of naphtol saga waste solution concentration (91,25±2,24) % at pH 7, reduced BOD content 63% and COD content 52%
