Gallium arsenate removal from waste waters
The aim of this paper is to study the loss of gallium (Ga) and arsenic (As) loss during the sedimentation of gallium arsenate (GaAsO4) from waste solutions of GaAs epitaxial production by chloride method. The solid wastes of this semiconductor manufacturing process are removed from technologica...
Guardado en:
| Autores principales: | , , |
|---|---|
| Formato: | article |
| Lenguaje: | EN |
| Publicado: |
D.Ghitu Institute of Electronic Engineering and Nanotechnologies
2005
|
| Materias: | |
| Acceso en línea: | https://doaj.org/article/496d928461a64feaa4ae5437cddcf8a7 |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| Sumario: | The aim of this paper is to study the loss of gallium (Ga) and arsenic (As) loss during
the sedimentation of gallium arsenate (GaAsO4) from waste solutions of GaAs epitaxial
production by chloride method. The solid wastes of this semiconductor manufacturing process
are removed from technological equipment by dissolution in an acidic etching solution. In
order to recover valuable Ga and very toxic As from these waste solutions we proposed to
precipitate them as gallium arsenate. Experiments have been conducted to determine the
migration of the two elements in filtrate and washing solutions as a function of pH for both
model and real industrial wastes. It has been determined the optimal interval of pH for
sedimentation, the losses of Ga and As present 0,01-0,053%. For model solutions the
sedimentation is optimal in the range of pH from 3,2 to 4,3, while in the case of real waste
solution this interval is 3,6-5,0. Comparative evaluation of the precipitation efficiency
revealed that for model solutions the arsenic loss during the precipitation is higher (0,5%),
and this can be explained by a different ratio of initial Ga3
and AsO4
3-
in model and real
solutions. The results described in this paper provide important guidelines for the
sedimentation of gallium arsenate from acidic waste solutions and indicate an overall
efficiency of the process that could lead to savings in cost and process time for industrial
effluent treatment technologies. |
|---|