Novel approach for high-efficiency recovery of titanium dioxide, hydrochloric acid, and organic solvents from titanium white waste acid

• Published in: Journal of cleaner production Vol. 315; p. 128105
• Main Authors: Song, Yongwei, Wang, Heru, Wang, Rui, Zhou, Jingcheng
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.09.2021
• Subjects: Calcination; Distillation; Hydrochloric acid; Organic solvents; Titanium dioxide; Titanium white waste acid; Distillation; Hydrochloric acid; Calcination; Titanium white waste acid; Organic solvents; Titanium dioxide
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2021.128105

In this study, the recovery efficiency of titanium dioxide (TiO2), hydrochloric acid (HCl), and organic solvents in titanium white waste acid (TWWA) is investigated via distillation combined with the calcination method. After distillation under vacuum condition at −0.071 MPa for 60 min, the recovery of diisobutyl phthalate (DIBP), hexane (C6H14), ethanol (C2H5OH), and HCl reached up to 70%, 76%, 68%, and 21%, respectively. Moreover, the metatitanic acid (TiO(OH)2) concentration in TWWA thick slurry obtained at the end of vacuum distillation increased from 72.60 to 416.11 g/L. Anatase and rutile were harvested after 60-min continuous calcination of TWWA thick slurry at 600 °C and 900 °C, respectively, and the TiO2 content in rutile was as high as 93%. Based on these results, we believe that TiO2, HCl, and organic solvents can be efficiently recovered from TWWA via vacuum distillation and high-temperature calcination. This method realizes the reduction and resource utilization of TWWA and has the advantages of simple technological process and low treatment cost. [Display omitted] •Integrated vacuum distillation and calcination is proposed to treat TWWA.•70% DIBP, 76% C6H14, 68% C2H5OH, and 21% HCl were recovered via vacuum distillation.•The amount of TWWA thick slurry was reduced by 46% after vacuum distillation.•Rutile with high-purity TiO2 was obtained from TWWA thick slurry after calcination.