Chromium, especially the hexavalent form, is toxic to humans. Industries like chrome plating, textile, electroplating discharge Cr(VI) in their effiuents. Wastes containing chromium are environmentally persistent and toxic, and cannot be degraded or detoxified biologically. Various techniques developed for the removal of heavy metals include chemical precipitation, ion exchange and adsorption. ...

This study was conducted to improve four characteristics as objectives:（1） high current efficiency, （2） surface brightness, and （3） hardness of chromium-carbon （Cr-C） alloy layers during electrochemical deposition from Cr（III） ions, （4） reproducibility the Cr-C layer formation repeated plating with a electroplating bath. A malonic-acid-containing sulfuric acid bath （sulfuric II） prepared by add...

EXTENDED ABSTRACT The removal of chromium from water and wastewater has caused increased research interest in recent years. Chromium exists in the environment mainly in one of two valence states: a) trivalent Cr(III), and b) hexavalent Cr(VI) form. Cr(VI) enters the environment primarily through industrial processes including the production of steel and metal alloys, chrome plating, dyes and pi...

The process of assessing the public health risk of exposure to particular environmental contaminants is complicated and full of assumptions and uncertainties (1,2). However, the problems of assessing risks for chromium exposure are unusually complex (3,4). The problems posed by current investigations of chromiumcontaminated soil in northern New Jersey (5), in part, provided the impetus for a co...

In this study, Taguchi experimental design has been used for the optimization of thickness of chromium layers. For this purpose brass materials have been electroplated under various conditions of the process. An orthogonal array (OA) was employed to analyze the effect of plating parameters on the characteristic of the thickness. Variables which were considered for working were as following; amo...

The large volumes of water used in rinsing operations in the plating industry may contain cyanides, chromium, nickel, and zinc, resulting in a substantial loss of valuable plating chemicals. From an economic viewpoint, particular consideration should be given to measures that will permit recovery of chemicals and water for reuse. In view of the wide variety of conditions found in plating practi...