CRYSTENGCOMM
·
2022
·Vol. 24
·期 39
·6987-6995
·
IF 3.756
Shujie Dai,Yangchun Tan,Yuhan Yang,Longfeng Zhu,Baogang Liu,Yanyan Du,Xuebo Cao
Organotemplate-free synthesis of zeolites assisted with zeolite seeds has been a hot topic in the past decade. Herein, we for the first time show an organotemplate-free synthesis of Al-rich S-ZSM-35 and S-ZSM-22 zeolites with the addition of ZSM-57 zeolite seeds. Notably, the adjustment of SiO2/Al2O3 and Na2O/SiO2 ratios in the starting gel to suitable values is an important factor in preparing the pure Al-rich S-ZSM-35 (Si/Al ratio at about 5) and S-ZSM-22 (Si/Al ratio at about 20) zeolites. The key to success is that the targeted ZSM-35 and ZSM-22 zeolite products have partly the same composite building units as the ZSM-57 zeolite seeds. The obtained Al-rich S-ZSM-35 and S-ZSM-22 zeolites show good crystallinity, typical crystal morphology, large BET surface area, and fully 4-coordinated aluminum species. In addition, as a typical example, the Al-rich S-ZSM-22 zeolite was evaluated by n-dodecane hydroisomerization reaction, which exhibits outstanding performance due to its Al-rich features (Si/Al ratio at about 20) compared with the conventional ZSM-22 zeolite (Si/Al ratio at about 30).
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Siqi Wu,Jianshan Chen,Rong Guo,Haoyi Tong,Shanshan Zong,Zhifang Diao,Yeyan Qin,Yuangen Yao
Efficient production of dimethyl carbonate (DMC) from methyl nitrite (MN) carbonylation based on PdCu/NaY zeolite catalysts is highly desired for industrial applications. The introduction of boron species into the initial gels of NaY synthesis is a cost-effective modification strategy for boosting the catalytic performance. It not only introduces trace amounts of framework boron but also regulates the distribution of framework aluminum (Al F ) species. Most importantly, the synergistic effect of framework boron and Al-rich region significantly enhanced the metal − support interaction, thus promoting more electrons to be transferred from metal to support. This strategy allows the palladium active species to remain in an electron-deficient state more easily. The carbon monoxide (CO) adsorption and the critical intermediate species *CH 3 COO are more easily formatted on PdCu/NaBY catalyst, which leads to superior weight-time yields (WTY DMC up to 1507·g·kg cat − 1 ·h − 1 ), and CO conversion to DMC (C CO up to 83 %). Our design is of great importance for developing metal-zeolites catalysts, which motivates the industrial application of Pd-based catalysts in the MN carbonation of DMC field.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Shuyang Shi,Chen Yang,Baozhong Ma,Hui Yang,Zhihe Cao,Yubo Liu,Yongqiang Chen,Chengyan Wang
Ga exhibits enrichment in coal-based solid waste, establishing it as a promising alternative source for Ga recovery. The HNO 3 pressure leaching process effectively achieves simultaneous leaching of Al and Ga while retaining most of the Fe in the residue. However, separating Ga from acidic solutions containing Fe and Al remains a persistent challenge in hydrometallurgy due to their similar physicochemical properties. Herein, a simplified and effective two-stage sequential solvent extraction process using acid phosphorus extractants (P507 and P204) for selective Ga recovery was proposed. Under optimized conditions, P507 removed 97.2 % of Fe from coal gangue HNO 3 leach liquor with limited co-extraction of Ga (10.1 %) and Al (5.7 %). Subsequent P204 extraction recovered 99.2 % Ga with only 9.1 % Al co-extraction from the Fe raffinate. Stripping with 2 mol·L –1 H 2 SO 4 yielded 88.0 % Ga recovery, with the extractants showing excellent regeneration and cycling performance. Mechanistic studies including FT-IR, UV-Vis, ESI-MS, and stoichiometric analysis confirmed coordination through both P = O and P–O–H groups, forming Fe(HA)A 3 and Ga(HL)L 3 complexes (A = P507; L = P204 ligands), respectively. This study presents a highly efficient approach for the separation of Fe/Ga/Al and Ga recovery from HNO 3 leach liquor, featuring exceptionally low acid depletion.
研究领域:
湿法冶金
·
溶剂萃取
·
资源回收
·
无机化学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2023
·Vol. 69
·期 6
·e18054
·
IF 3.7
Feng Xiong,Chen Ji,Shengzhi Gan,Peng Liang,Yi Huang,Jin Shang,Baoyu Liu,Jinxiang Dong
Mesoscopically structured ZSM-5 nanosheets were prepared as highly active catalysts for the alkylation between toluene with methanol. The results showed that the Brønsted acid sites of ZSM-5 nanosheets were mainly distributed on the external surface in aluminum-rich zeolites owing to the charge-balance between positive quaternary ammonium cation (N + ) in C ph-10-6-6 , Na + ions and negative aluminosilicate species. In addition, it revealed that high alkalinity was easier to depolymerize the Si O Si species in Aluminum-rich synthesis gel, and the high alkalinity was required for silica-rich systems to dissolve silica species in order to finish the self-assemble process, leading to ZSM-5 nanosheets with high alkalinity presenting enhanced catalytic performance. Moreover, the optimized ZSM-5-50-2.5 was effective for the alkylation between toluene and methanol with toluene conversion of up to 50%, and it was stably operated for 48 h under the harsh conditions of WHSV = 32.5 h −1 with a desired stability.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）