Aplicação do ciclo PDCA na análise da pureza do cianeto de sódio

Abstract

Alkaline copper plating plays a crucial role in electroplating, providing adhesion in the coating of parts such as door handles. The sodium cyanide (NaCN) in this bath plays a vital role in the solubilization of copper cyanide, being a key component for the success of the process. Because of this, it is essential to monitor and analyze the concentration and purity of sodium cyanide to avoid harmful variations in the bath and the final product. This work focused on analyzing these aspects, evaluating data that revealed substantial errors, adversely impacting the quality of the alkaline copper bath. The standard testing methodology adopted by the company involves weighing 3 to 5 grams of supplied sodium cyanide and subsequent titration with silver nitrate (AgNO3). It was observed that, as the amount of mass increases, the volume spent also increases, but the data collected in this study indicated non-linear variations in this relationship. Furthermore, when analyzing the pre-established equation to calculate purity in the laboratory, an inversely proportional relationship was observed between the volume spent and the mass. The main flaws identified include the lack of repetition in the tests, the use of sodium cyanide with a concentration lower than the stipulated standard and a wide weight range in the analyses. Given these deficiencies, the need to improve the process was recognized, opting for the PDCA Cycle as a corrective methodology. This choice reflects a strategic commitment to continuous improvement, establishing an iterative cycle of planning, execution, verification and action. The implementation of PDCA not only sought to correct immediate failures, but also to establish lasting standards of efficiency and quality for the company PADO S.A. The integration of PDCA into the analysis of the purity of sodium cyanide aimed to ensure the conformity of the alkaline copper bath, avoiding damage to the final product and reducing rework in the process. This approach contributed significantly to operational efficiency and cost reduction.