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Paraffin Oxidation Studies International Journal of Engineering Innovation & Research Volume 2, Issue 1, ISSN: 2277 – 5668 Paraffin Oxidation Studies Mrs. S. J. Purohit, Dr. Milind Pradhan Prof. Purohit S. J. is a Research Scholar at Bhagwant University & Working at Thadomal Shahani Engg. College, Bandra Mumbai-50. Email:[email protected] Abstract – The oxidation of paraffin has been studied with Many processes were developed to manufacture fatty keen interest by several workers from all over the world; as acids of various molecular weights. The manufacture of oxidation leads to the introduction of various functional higher fatty alcohols; which have potential uses as starting groups in hydrocarbon chains. Processes involving the material for the manufacturing of lubricating oil, additives, Oxidation of Paraffin’s in the liquid phase, using air or synthetic lubricating oil, plasticizers and others. A more oxygen are of great importance to industrialized economies because of their role in converting petroleum hydrocarbon selective process for the oxidation of paraffin to alcohols feed stocks such as alkanes, olefins and aromatics into has been conducted by Bashkirov , khim and co workers; industrial organic chemicals important in the polymer, who conducted the reaction in the presence of Boric acid. petrochemicals ,cosmetics and detergent industries. The alcohols are stabilized in the form of their esters; The oxidation leads predominantly to the formation of which are resistant to further oxidation and hence very secondary alcohols consisting of a mixture of all possible high selectivity is achieved.[2,3] isomers with the same number of carbon atoms in the Paraffin oxidation mechanism molecules as the initial hydrocarbons. The secondary 1st stage alcohols which are oxidation products of paraffin exhibit excellent hydrolytic, oxidative and color stability, because of Hydrocarbon → Hydro peroxide the nature of their branching. These alcohols have lower nd melting points than straight chain alcohols of corresponding 2 stage length, while retaining their high temperature stability. The Hydro peroxides → ketones → acids oxidation of paraffin wax to fatty acids is carried out in 0 0 temperature range 110 C- 140 C. ↨↨ ↑ Alcohols Paraffin oxidation which is carried out by ALFOL, Oxo- processes, are high temperature, high pressure processes which utilize expensive catalysts, making them energy intensive as well as expensive. The maximum conversion achieved yet by existing processes is 15% for a batch time of 4 hours. A cheaper alternative in this article has been studied, in which paraffin Oxidation has been carried out in a foam reactor at moderate temperature and pressure with suitable catalyst , the output of the products is increased up to 62%. Keywords – Paraffin Oxidation, Catalyst, Foam Reactor. INTRODUCTION Fig.1. Paraffin Oxidation Mechanism The oxidation of paraffin has been the keen interest by several workers from all over the world; as the oxidation The oxidation leads predominantly to the formation of leads to introduction of various functional groups in secondary alcohols consisting of a mixture of all possible hydrocarbon chains, even in saturated ones. Liquid phase isomers with the same number of carbon atoms in the oxidation of paraffin wax to fatty acids was first exploited molecules as the initial hydrocarbons. in Germany to replace partly the import of fats during The secondary alcohols which are of oxidation products Second World War,Since then the process has been of paraffin exhibit excellent hydrolytic ,oxidative and co successfully commercialized in several countries like lour stability because of the nature of their branching; U.S.A, U.S.S.R, and East Germany. [1] These alcohols have lower melting points than straight Company like Petrolite Corporation and Alox chain alcohols of corresponding length while retaining Corporation manufacture a wide range of oxygenated their high temperature stability. Their possible applications hydrocarbons. These products are produced by the are as alcohol sulphates or ether sulphates for use in controlled liquid phase partial oxidation of various detergents, cosmetics and industrial processes as petroleum fractions. Normally these oxides are mixtures of ethoxylates or propoxylates as non-ionic surfactants for a organic acids.;oxy acids etc.They vary from one another in wide variety of industrial uses as esters for lubricants, molecular weight (determined by raw material selected). emulsifiers, antioxidants, polymers, alkyl halides, amines and esters of oxidation. These oxidates are used in rust and ether amines used as petroleum additives and alcohol preventives, oil soluble lubricating agents, emulsifiers, or themselves as emulsifiers, solublizers, antifoams etc. [4] demulsifies, corrosion inhibitors etc. Copyright © 2013 IJEIR, All right reserved 75 International Journal of Engineering Innovation & Research Volume 2, Issue 1, ISSN: 2277 – 5668 AVAILABLE TECHNOLOGIES about 2 minutes after injection ,then to increase the temperature at the rate of 5 per minute to 240 and finally The oxidation of paraffin wax to fatty acids is normally to maintain its temperature for 5 minutes .The injection carried out in temperature range 110 0C- 140 0C. In the port temperature is maintained at about 220,the carrier gas reaction, the effect of mass transfer can be eliminated by is helium with a linear velocity of about 50 cm per second. keeping sufficiently high value of air flow rate initially. Chromatographs are in terms of absorbance vs retention Nesmelov and coworkers [6] have reported significant time. improvement in yield and quality of fatty acids by continuous foam phase oxidation. And recommended use EXPERIMENTAL DETAILS of 5 %alcohol from sperm whale oil along with soda ash to obtain homogeneity in foam phase. Higher conversion The foam reactor used in the present experimental work levels beyond 50 % leads to the formation of more of more was a laboratory scale reactor similar to that described by oxygenated and water soluble acids and hence the Bashkirov and Solviet process, having 6.38 cm diameter; oxidation is stopped when the degree of conversion is and100cm length. Reactor has been made from glass; between 30 to 50 %. advantage is non-corrosive in nature, transparent, and Paraffin oxidation which is carried out by ALFOL, Oxo- resistant to many chemicals. Glass reactors were packed processes, are high temperature, high pressure processes with packing material, rasching rings, up to 15 cm height; which utilize expensive catalysts, making them energy size of rasching rings 12*12 mm,. For measuring flow intensive as well as expensive. The maximum conversion rates, rota meters were installed at the inlet for both air and achieved yet by existing processes is 15% for a batch time water. having Range (1-250 lpm) .Paraffin oil was heated of 4 hours. The rate of oxidation may be increased by in SS vessel having capacity 5lits.SS vessel was provided increasing the inter -facial area by Foam in a reactor, with internal cladding of alumina with internal heater (0- where we can get significant improvement in the yield and 200oc) and temperature indicator. Samples after oxidations quality of fatty acids by continuous foam. were collected in a flask having capacity 250 ml. Extensive information is available regarding paraffin Experimental Procedure:- oxidation mechanism. However; most of the information’s The initial temperature has been maintained between 130- are relevant for paraffin oxidation processes. and its 170 °C. studies in batch and continuous operations, Very little The air flow-rate has been maintained between 1-5 litres information is available for the paraffin oxidation studies per minute and water flow rate, one lit/min.. The catalysts in foam reactor. used were: Boric acid; Potassium permanganate; A cheaper alternative in this paper has been studied, in Magnesium Oxide. The concentration of the catalyst has which paraffin Oxidation has been carried out in a foam been kept between 5-10%. reactor at moderate temperature and pressure with suitable The surfactant used was Sodium laurel sulphate. in a catalyst , the output of the products are increased up to slurry form, Concentration was kept max 5 % by weight. 62%.[5,7,8]. Chemicals used: - Paraffin oil, a combination of catalyst such as magnesium Oxide (MgO), Potassium paramaganet METHODOLOGY (KMnO4) and boric acid with different proportions. The reaction has been carried out for about 2, -5 hrs. The major products of paraffin oxidation are The samples were collected at the interval of one hr. 1. Fatty Acids 2. Fatty Alcohols Samples were collected from bottom (50 ml app.) and 3. Esters 4. Aldehydes and Ketones were analyzed for acid contents by titration. The fatty Fatty acid concentration equal or higher than 1 mM may alcohol analysis has been performed using GC -mass be easily determined by titrimetry, .Titrimetry was Spectrophotometer. Fatty acids contained in the alcohols classically used to determine the acid value (free fatty were separated by Saponification and subsequent content) of vegetable oils and fats. This acid value is distillation. Alcohols have been set free by Hydrolysis. defined as the number of mg of KOH required to Primary alcohols were prepared by vacuum distillation. neutralize. The bottom Products contained only secondary alcohols. The Fatty acids. Contained in 1 gm of fat. Which were analysed by GC -mass Spectrophotometer. The acid value is calculated by formula = 56.1*N*V/M The product stream was separated into organic layer and Where V is the number of ml of KOH solution used N is aqueous layer using a separating funnel. exact normality, M is the mass in gm of sample. The properties of paraffin oil:- The complete product analysis has been carried out by 1. Appearance: Clear colourless, viscous liquid. modern analytical tool like, GC-Mass Spectrophotometer. 2. Odour: Odourless GC–MS Details:-The gas chromatograph is equipped 3. Solubility: Negligible (<0.1 %) with a flame –ionization detector maintained at a 4. Specific gravity: 0.86-0.91 temperature of about 260, a split less injection system, and 5. Volatiles by volume at 21°C: Nil a 0.53 mm * 30m fused silica capillary column bonded 6.
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