... : High purity (the content of NaOH can reach 99%), even particles, few impurity, good fluidity, easily to ... to prevent the dust and the residual solid caustic soda pearl from entering the equipments, thus to produce ... grain: 1.0-1.6mm (diameter) 5. Quality index: Testing result: NaOH: 99.4%, Na2CO3:0.27%, NaCl:0 ... 0.002% Testing result of the Food Grade: NaOH: 99.1%, Na2CO3:0.56%, As :<0.0003%, Heavy ...