Method for Preparing the Oxysulfides of Rare Earth Elements
Sulfur dioxide is one of the major components of acid rain emitted into the atmosphere resulting from fuel combustion and ore roasting process. The need for sulfur dioxide removal has been demonstrated, but the high cost of existing processes has prevented the wide application of sulfur dioxide removal from coal-fired power plants, smelters etc. There are many existing processes, but the capital and running costs are usually high and the operation is complicated. Even the most popular ones such as wet and dry scrubbing methods, which utilize a large amount of sorbents to absorb sulfur dioxide, only turn harmful gaseous pollutants into their liquid or solid forms, which also require further treatments.
The invention relates to the removal of sulfur dioxide from waste gas streams by catalytic reduction using activated lanthanum oxide and its derivatives as the catalyst, and using carbon monoxide as the reductant. The oxide and its derivative catalyst synthesized by hydration, heat-treatment and sulfidation, are activated in a reaction stream containing sulfur dioxide and carbon monoxide. This preparation procedure is unique and can also be applied to the production of oxysulfide phosphorous, which has wide application in TV manufacturing and in lighting.
1. The conversion of sulfur dioxide to elemental sulfur involves only one stage, making the process simple to design and operate
2. Low carbonyl sulphide (COS) formation
3. High conversion rate
4. The catalyst can be prepared from low cost, simple starting materials economically and with guaranteed quality
- TV screen coating material
- Removal of sulfur dioxide generated by coal-fired power plants
Patent Number: US5795554A
Application Number: US1997790600A
Inventor: Fang, Ming | Ma, Jian Xin | Lau, Ngai Ting
Priority Date: 16 Dec 1994
Priority Number: US5795554A
Application Date: 29 Jan 1997
Publication Date: 18 Aug 1998
IPC Current: B01J002110 | B01J002704 | C01B001704 | C01F001700
US Class: 423263 | 4230211 | 42324401 | 42324409 | 423247 | 502216 | 502302
Assignee Applicant: The Hong Kong University of Science & Technology
Title: Method for preparing the oxysulfides of rare earth elements
Usefulness: Method for preparing the oxysulfides of rare earth elements
Summary: USE The oxysulphide is a catalyst for the catalytic reduction of SO2 in waste gas streams so as to form CO2 and sulphur from a stream containing CO and SO2 in a single step at a high conversion rate and with minimal formation of COS.
Novelty: Oxysulphide compound of rare earth prepared by hydrating oxide and sulphidising resulting hydroxide with carbon mon:oxide and sulphur di:oxide to form catalyst for sulphur di:oxide reduction
化工/材料
化工/材料應用
29 Jan 1997
US 5795554
TTC.PA.016
香港
