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The typical hydrofluoric acid (HF) alkylation unit requires far less acid than a sulfuric acid unit to achieve the same volume of alkylate. The HF process only creates a small amount of organofluorine side products which are continuously removed from the reactor and the consumed HF is replenished.
Hydrogen fluoride (HF) and aluminium chloride (AlCl 3) are the two major catalysts for the alkylation of benzene with linear mono-olefins. The HF-based process is commercially dominant; however, the risk of releasing HF (a poisonous substance) into the environment became a concern particularly after the Clean Air Act Amendment. In 1995, a solid ...
Alkylation in petroleum refining is a process through which olefins and parafins are combined to form high molecular weight isoparaffins. [3] Alkylation uses hydrofluoric acid (hf acid), a highly corrosive substance that dissolves a wide range of materials, particularly the oxides. Monel valves are generally used in the most critical phases of ...
The process involves dehydrogenation of n-paraffins to olefins, and subsequent reaction with benzene using HF as catalyst. For example, in oil refineries "alkylate", a component of high- octane petrol ( gasoline ), is generated in alkylation units, which combine C 3 and C 4 olefins and iso -butane .
The company invented an HF alkylation process in 1940. [13] The American petrochemical industry took off, first making such as styrene , ethylene , propylene and butadiene . [ 2 ] After the war, it formed a subsidiary, Phillips Chemical Co., which entered the fertilizer business by producing anhydrous ammonia from natural gas. [ 14 ]
In commercial applications, the alkylating agents are generally alkenes, some of the largest scale reactions practiced in industry.Such alkylations are of major industrial importance, e.g. for the production of ethylbenzene, the precursor to polystyrene, from benzene and ethylene and for the production of cumene from benzene and propene in cumene process:
The optional second step (for bare silicon wafers) is a short immersion in a 1:100 or 1:50 solution of aqueous HF (hydrofluoric acid) at 25 °C for about fifteen seconds, in order to remove the thin oxide layer and some fraction of ionic contaminants. If this step is performed without ultra high purity materials and ultra clean containers, it ...
As is typical for an S N 2 process, benzylic, allylic, and α-carbonylated alkyl halides are excellent reactants. Even though alkyl chlorides are poor alkylating agents ( gem -dichlorides especially so), amines should not be handled in chlorinated solvents such as dichloromethane and dichloroethane, especially at high temperatures, due to the ...