Studies On Resource Recovery Of Industrial Wastes

The treatment and utilization of industrial wastes was studied centering on resource recovering. The disposal aluminum from an aluminum factory and the by-product ferrous sulfate of titanium white industry were selected as examples. Methods were proposed to reuse these industrial wastes. Furthermore, a rapid method for the determination of total phosphorus in industrial water was reported in this thesis.The thesis is divided into three sections.In the first section, ultra-fine and high-pure aluminum silicate was synthesized using aluminum waste from a local aluminum surface treatment factory. The waste was soaked in sulfuric acid and aluminum was dissolved. The solution was subjected to extraction with an organicphosphorus. extractant, P204, The ferric iron was strongly extracted and separated from bulk solution at pH=2.5. The purified solution was used to synthesize ultra-fine aluminum silicate by controlling the concentration of aluminum sulfate and water glass. The quality of the synthesized product met the Standard of Chinese Industry.Section 2 is about a new approach to the rapid synthesis of polymeric ferric sulfate was proposed with ferrous sulfate, the by-product of titanium white industry as the crude material. The process was conducted under the conditions of normal temperature and normal pressure with hydrogen peroxide as the oxidant. Parameters, such as dosages of hydrogen peroxide and sulfuric acid were optimized in terms of the characteristics of the products, such as the residue ferrous ions and basicity. In comparison with other synthesis methods, the present method offers the advantages of less prophase investment, simpler process and no secondary pollution. The quality of the product obtained could attain to the Chinese national first-level standard of polymeric ferric sulfate. It showed the excellent decolourization effect when applied to the dye wastewater treatment.A UV photocatalytic digestion system for the highly sensitive flow-inject spectrophotometric determination of total phosphorus in recycling water was described in the last section. Sample was digested in a UV photo-reactor by using TiC>2 and potassium persulfate. A detection limitC 3 o )of 0.02 mg/L was achieved at a sampling frequency of 30 h"1 .The relative standard deviation was 0.21% for the determination of 0.4mg/L phosphorus (n=ll)o This method can be applied for the detection of total phosphorus in recycle water with satisfactory results.