Sulfur process technology

Diesel Fuel. Eederal diesel specifications were changed to specify a maximum of 0.05% sulfur and a minimum cetane index of 40 or a maximum aromatics content of 35 vol % for on-road diesel. Eor off-road diesel, higher sulfur is allowed. CARB specifications require 0.05% sulfur on or off road and 10% aromatics maximum or passage of a qualification test. Process technologies chosen to meet these specifications include hydrotreating, hydrocracking, and aromatics saturation. 

Combustion of Sulfur. For most chemical process appHcations requiring sulfur dioxide gas or sulfurous acid, sulfur dioxide is prepared by the burning of sulfur or pyrite [1309-36-0], FeS2. A variety of sulfur and pyrite burners have been developed for sulfuric acid and for the pulp (qv) and paper (qv) iadustries, which produce and immediately consume about 90% of the captive sulfur dioxide produced ia the United States. Information on the European sulfur-to-sulfuric acid technology (with emphasis on Lurgi) is available (255). 

A disadvantage of the hydrocarbon—sulfur process is the formation of one mole of hydrogen sulfide by-product for every two atoms of hydrogen in the hydrocarbon. Technology for efficient recovery of sulfur values in hydrogen sulfide became commercially available at about the same time that the methane—sulfur process was developed. With an efficient Claus sulfur recovery unit, the hydrocarbon—sulfur process is economically attractive. 

Interactions of the Sulfur and Nitrogen Cycles Microbiology and Process Technology (P. M. Chazal, P. N. L. Lens)... 

The new commercially available technologies concern the removal of sulfur with a minimum lost of octane rating. SCANfming and Prime G+ are the process technologies licensed by ExxonMobil and IFP, respectively. In SCANfining (Fig. 4), the complete naphtha (full range naphtha) is treated, with a proprietary catalyst. 

Marzona, M. Pessione, E. Di Martino, S., and Giunta, C., Benzothiophene and dibenzoth-iophene as the sole sulfur source in Acinetobacter growth kinetics and oxidation products. Fuel Processing Technology, 1997. 52(1-3) pp. 199-205. 

The aMDEA (Activated Methyl Diethanolamine) process removes CO2, H2S and trace sulfur compounds from natural gas and syngas via a pressurized wash with activated diethanolamine. This process was developed by BASF. The first unit was started up in 1971 in Germany and in 2002 it was used in more than 140 plants with 20 more under construction1. About 75 of these plants involve another process technology (MEA, DEA, Benfield, etc.) that was modified to use the aMDEA technology. 

Premixing. The development and engineering of the SA processing technology is based on extensive laboratory and field experience with SA binder and SA mixes. The key aspects and requirements for the incorporation of sulfur in paving mixes for industrial-scale mix production are uniformity of dispersion, SA ratio, and coating of the aggregate by the binder. 

The schematic of the recent process technology for the Pittsburgh and Midway Solvent Refined Coal process is shovm in Figure 1. The salient aspects of the process technology as they aflFect economics are (a) delivery of the product as a solid fuel product or as a hot liquid (b) byproducts—light liquid hydrocarbon, sulfur, and electrical power (c)... 

There are many methods for the desulfurization of nature gas, which can be classified into dry desulfurization, wet desulfurization, and catalytic adsorption. In the dry desulfurization, some solid sorbents, such as iron oxide, zinc oxide, activated carbon (AC), zeolites, and molecular sieves, are used. In wet desulfurization method, liquid-phase chemical/physical solvent absorption systems are usually used for scrubbing H2S amine-based processes are subject to equipment corrosion, foaming, amine-solution degradation, and evaporation, and require extensive wastewater treatment. As a result, this sulfur removal technology is complex and capital intensive,44 although the processes are still employed widely in the industry. The desulfurization of coal gasification gas will be reviewed in detail in Section 5.5. In the catalytic-adsorption method, the sulfur compounds are transformed into H2S by catalytic HDS or into elemental sulfur or SOx by selective catalytic oxidation (SCO), and then, the reformed H2S and SOx are removed by the subsequent adsorption. 

Knudsen, K.G., Cooper, B.H., and Topsoe, H. Catalyst and process technologies for ultra low sulfur diesel. Applied Catalysis. A, General, 1999, 189, 205. 

A company is considering construction of a phosphoric acid plant employing Haifa process technology, which is to use its own byproduct hydrochloric acid for acidulation. Present-day cost of sulfuric acid is 110/tonne. 

Scheme 2 Basic principle of the S Zorb Sulfur Removal Technology process developed by Phillips Petroleum for sulfur removal from liquid fuel at elevated temperatures under low H2 pressure.

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