Modification method for promoting rapid formation of gamma-FeOOH layer on surface of scrap iron by iron ions

• Main Authors: MA JIETING, LIN XIAOZI, MA LUMING
• Format: Patent
• Language: Chinese; English
• Published: 13.07.2021
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; THEIR RELEVANT APPARATUS; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention relates to a modification method for promoting rapid formation of a gamma-FeOOH layer on the surface of scrap iron by iron ions. The modification method comprises the following steps of: (1) selecting scrap iron waste of low-carbon steel, medium-carbon steel and low-alloy structural steel, and pretreating the scrap iron waste; (2) modifying the scrap iron obtained in the step (1) in a mixed modification solution containing an oxidant and an accelerant, wherein the modification liquid is prepared from the following components in percentage by mass: 0.05% to 0.45% of the axidant, 0.025% to 0.5% of the accelerant, 0 g/L to 2 g/L of polyvinyl butyral resin, 0 g/L to 1 g/L of polyethylene glycol and the balance water, the pH of the modification solution is 2 to 4, and the temperature of the modification solution is 15 DEG C to 40 DEG C; (3) after the modification in the step (2) is completed, adding an oxidant into a modification system again to maintain a mass concentration of the modification syste