Green Recovery of Titanium and Effective Regeneration of TiO₂ Photocatalysts from Spent Selective Catalytic Reduction Catalysts

The extensive use of selective catalytic reduction (SCR) catalysts will afford many spent SCR catalysts. The mass fraction of the titanium component is over 80% in spent SCR catalysts, but currently, it is usually thrown away without proper recycling. This work aims to develop a clean, green, and economical approach to recovering titanium and regenerating TiO₂ photocatalysts from spent SCR catalysts based on the conversion of the titanium component. This titanium component is converted into metastable α-Na₂TiO₃ with high efficiency (>98%) using a NaOH molten salt method, and the optimal conditions were found to be a roasting temperature of 550 °C, a NaOH-to-spent-SCR-catalysts mass ratio of 1.8:1, a roasting time of 10 min, and a NaOH concentration of 60–80 wt %. And a possible chemical reaction mechanism is proposed. A subsequent hydrothermal treatment of α-Na₂TiO₃ regenerates TiO₂ photocatalysts with high purity (>99.0%) that can satisfy commercial requirements. In addition, the present iron element contained in spent SCR catalysts is doped into regenerated TiO₂ photocatalysts, resulting in providing visible-light-driven photocatalytic activities. The regenerated TiO₂ photocatalysts possess superior photocatalytic degradation capacities for dye pollutants and can be used to efficiently treat wastewater. This work introduces a promising technology for the cyclical regeneration of titanium from spent SCR catalysts

Sustainable Approach for Spent V₂O₅–WO₃/TiO₂ Catalysts Management: Selective Recovery of Heavy Metal Vanadium and Production of Value-Added WO₃–TiO₂ Photocatalysts

In order to control nitrogen oxides emissions, V₂O₅–WO₃/TiO₂ catalysts are widely applied in coal-fired power plants. Consequently, a large number of V₂O₅–WO₃/TiO₂ catalysts are spent annually because of their short operating life. Although these spent catalysts contain amounts of heavy metals, they have also been regarded as a potential secondary resource for the recovery of valuable elements titanium, tungsten, and vanadium. Therefore, this study developed an efficient method for selective leaching of heavy metal vanadium with an “H₂SO₄ + Na₂SO₃” acid reduction system. The use of this leaching solution achieved nearly 100% efficiency in vanadium removal, and the effects of the leaching parameters on the vanadium leaching efficiencies were investigated. Subsequently, the titanium-enriched residue obtained from the leaching process was used to produce high-performance WO₃–TiO₂ photocatalysts with dominant {001} facets via a hydrothermal treatment. The influence of the amount of hydrogen fluoride on the morphology and percentage exposure of the {001} facets of the photocatalysts was studied systematically. The method proposed in this study constitutes a novel and sustainable approach for the disposal of spent V₂O₅–WO₃/TiO₂ catalysts

Low-Cost Y‑Doped TiO₂ Nanosheets Film with Highly Reactive {001} Facets from CRT Waste and Enhanced Photocatalytic Removal of Cr(VI) and Methyl Orange

In this paper, efficiency recovery of rare earth elements from cathode ray tubes (CRT) waste. Moreover, recycled yttrium was also served as raw material to produce a low-cost Y-doped TiO₂ nanosheets film with exposed {001} facets. An etching/dissolution growth mechanism was postulated by systematically investigating the influence of the reaction time. The synergistic effect of the Y dopant and the dominant {001} facets endows TiO₂ nanosheets film with excellent activity in the photoremoval of Methyl Orange (MO) and Cr­(VI). A possible mechanism of photoremoval of MO and Cr­(VI) is proposed. This study not only contributes to recycling methods for CRT waste but also presents a new way to prepare low-cost sustainable photocatalytic materials using economically viable waste

Additional file 1: of High genetic abundance of Rpi-blb2/Mi-1.2/Cami gene family in Solanaceae

Primers for cloning of LRRs. (DOCX 13 kb

Spectrum of De Novo Cancers and Predictors in Liver Transplantation: Analysis of the Scientific Registry of Transplant Recipients Database

<div><p>Background</p><p>De novo malignancies occur after liver transplantation because of immunosuppression and improved long-term survival. But the spectrums and associated risk factors remain unclear.</p><p>Aims</p><p>To describe the overall pattern of de novo cancers in liver transplant recipients.</p><p>Methods</p><p>Data from Scientific Registry of Transplant Recipients from October 1987 to December 2009 were analyzed. The spectrum of de novo cancer was analyzed and logistic-regression was used to identify predictors of do novo malignancies.</p><p>Results</p><p>Among 89,036 liver transplant recipients, 6,834 recipients developed 9,717 post-transplant malignancies. We focused on non-skin malignancies. A total of 3,845 recipients suffered from 4,854 de novo non-skin malignancies, including 1,098 de novo hematological malignancies, 38 donor-related cases, and 3,718 de novo solid-organ malignancies. Liver transplant recipients had more than 11 times elevated cancer risk compared with the general population. The long-term overall survival was better for recipients without de novo cancer. Multivariate analysis indicated that HCV, alcoholic liver disease, autoimmune liver disease, nonalcoholic steatohepatitis, re-transplantation, combined transplantation, hepatocellular carcinoma, immunosuppression regime of cellcept, cyclosporine, sirolimus, steroids and tacrolimus were independent predictors for the development of solid malignancies after liver transplantation.</p><p>Conclusions</p><p>De novo cancer risk was elevated in liver transplant recipients. Multiple factors including age, gender, underlying liver disease and immunosuppression were associated with the development of de novo cancer. This is useful in guiding recipient selection as well as post-transplant surveillance and prevention.</p></div

Overall characteristics of liver transplant recipients.

<p>Overall characteristics of liver transplant recipients.</p

Additional file 1: Figure S1. of Selective sweep with significant positive selection serves as the driving force for the differentiation of japonica and indica rice cultivars

PCA plots of the first two components before (a) and after (b) sample selection. Figure S2. The proportions of the genome-wide diversity within the groups of japonica, indica and wild rice and divergence between japonica and indica group. Figure S3. Diversity/divergence relationship between rice groups. Figure S4. GO statistic of the DR-I regions. Figure S5. GO statistic of the DR-II regions. Figure S6. Clustered regions of DR-I. Figure S7. Clustered regions of DR-II. Table S1. List of 330 rice cultivars downloaded from the 3 K-rice project. Table S2. PCA value for each sample. Table S3. List of African cultivated rice (O. glaberrima) and wild rice (O. rufipogon and O. nivara) used to generate phylogenetic tree. Table S4. List of wild rice obtained from Huang et al. used in this project. Table S5. SNP genotype of DR-I. Table S6. SNP genotype of DR-II. Table S7. List of 163 genes in the 28 DR-I regions. Table S8. List of 110 genes in the 28 DR-II regions. (PDF 2465 kb

Overall View of de novo cancer in liver transplant recipients.

<p>Overall View of de novo cancer in liver transplant recipients.</p

De novo malignancies in primary diagnosis.

<p>(PSC = primary sclerosing cholangitis, ALD = alcoholic liver disease, PBC = primary biliary cirrhosis, HCV = hepatitis C, NASH = cryptogenic cirrhosis, AIH = autoimmune hepatitis, AHN = acute hepatic necrosis, HBV = hepatitis B, Metab = metabolic disease.)</p

Logistic regression analysis.

<p>Logistic regression analysis.</p