Synthesis of 3,4,5-trihydroxy-2-[(hydroxyimino) methyl] benzoic acid as a novel rust converter

Figures & data

Scheme 1. Synthesis of RC-GAO.

Table 1. The composition of residual rust coatings.

Material	Mass (%)
Water	22
RC-GAO	5
Propanediol	2.3
Thickener	0.1
Texanol	0.7
SiO2	1.5
Dispersant	0.1
Sericite	12.6
Defoamer	0.2
Emulsion	55.5

Figure 1. IR spectra of (a) iron rust; (b) iron rust treated with rust converter; and (c) the rust converter.

Figure 2. Optical images of the rusty steel sample before (a) and after (b) the treatment with the rust converter. The brown rust in the sample plate is converted into a shiny black protective iron chelate film after the treatment with RC-GAO.

Figure 3. SEM of rusty samples before (a) and after (b) conversion treatment.

Figure 4. XRD patterns for the rusted samples before and after treatment with the rust converter (L: lepidocrocite, M: magnetite, G: goethite)

Table 2. The result of the salt spray test.

Test time (h)	Blistering
2	8F
6	8F
12	7F
24	6M
120	4MD