CPE 604 PLANT DESIGN PRODUCTION OF PHTHALIC ANHYDRIDE

Phthalic anhydride is the organic compound whose applications are mainly in the manufacture of phthalate plasticizers, phthalocyanine dyes, polyester resins and numerous fine chemicals. It is an anhydride of phthalic acid with a colorless nature. This colorless solid is an important industrial chemical, especially for the large scale production of plasticizers for plastics. Its major outlets are phthalate plasticizers, unsaturated polyesters and alkyd resins for surface coatings while its smaller volume applications include polyester polyols, pigments, dyes, sweeteners and flame retardants The present study illustrates a way of producing phthalic anhydride (PA) in a continuous plant, with 99.8 % wt purity, through the oxidation of o-xylene. Maleic anhydride is also obtained as a by-product of the process with 99.5% wt purity. The process was simulated using the process simulator software ASPEN Plus and improving the purity of Phthalic anhydride obtained by introduction of suitable e...

These papers illustrate a reactor design to produce Phthalic anhydride (PAN) in continuous plant through the oxidation of o-xylene. Maleic anhydride is also obtained as by-product in this process. Pressure drop, side reactions and maintaining a relatively constant driving force for heat transfer are considered in this design. The production of phthalic anhydride is approximately 20,000 tons/year as required. The process was simulated using the process simulator Aspen plus.

International Archives of Occupational and Environmental Health, 1991

A total of 23 phthalic anhydride (PA)-exposed workers (air levels up to 17 mg/m 3 ) showed significantly (P< 0 01) more workrelated symptoms in their eyes ( 48 % vs 6 %) and nose ( 39 % vs 0) than did 18 unexposed control subjects Two of the exposed workers had PAassociated asthma Surprisingly, the control group exhibited significantly (P < 0 05) more symptoms of nonspecific bronchial hyperreactivity ( 44 % vs 13 %) The exposed workers showed significantly higher levels of total serum Ig E (medians, 32 vs 15 k IU/l, P < 0 05), although values for specific Ig E against PA did not differ This may indicate that such exposure can facilitate the entry of common allergens There was a significant difference in PA-specific Ig G lenzyme-linked immunosorbent assay (ELISA) ratios 0 21 vs 0 12 ; P< 0 01 l There were no differences in lung function with regard to vital capacity (VC) and forced expiratory volume (FEV 1 ), closing volume expressed as a percentage of VC (CV%), volume of trapped gas (VTG) before and after inhalation of metacholine, or carbon monoxide transfer factor (TLCO), whereas exposed workers displayed significantly higher late expiratory flow rates (MEF 50 and MEF 2 5 ) In a l 99 m Tcl-diethylenetriamine penta-acetate (DTPA) clearance test, there was no difference between exposed subjects and controls In summary, exposure to PA did not cause subclinical effects of the lungs Subjects with lowerairway symptoms showed lower FEV 1 , MEF 5 0 , and MEF 2 5 values and higher VTG (after metacholine) than did those without symptoms Six subjects with chronic bronchitis displayed significantly (P < 0 05) higher VTG (before metacholine) and TLCO, than those without this ailment Thus, VC, CV and the l 99 m Tcl-DTPA test were not affected by the lung disorder.

Phthalates, also known as phthalate esters, an alkyl aryl esters of 1, 2 benzenedicarboxylic acid. They have a broad range of applications, and are widely used as plasticizer (as vinyl softener). Phthalates act as endocrine disrupters and due to the increased awareness of its adverse effects on environment and health of living organisms, biodegradation of phthalates are now researched at a faster pace. This review highlights the applications of phthalates, their adverse effects on health, regulatory status and biodegradation of phthalates by pure and mixed bacterial cultures and fungi.

Occupational and Environmental Medicine, 1998

Objectives-To estimate past exposure to phthalic (PA), trimellitic (TMA) and maleic anhydride (MA) in three alkyd resin and one cushioned flooring factory to estimate exposure-response relations in a retrospective cohort study. Methods-Personal exposure measurements were carried out in 1992 and quantitative and qualitative information on past exposure and production processes were collected. Job titles were ranked by decreasing exposure and amalgamated into job categories and exposure groups. Multiplication factors for back calculating past exposure levels were estimated with past exposure data, or if no such data were available these factors were estimated by a panel of occupational hygienists. Exposure levels were back calculated starting with the exposure levels in 1992. Results-High exposures to PA were estimated to have occurred among workers operating the PA melting pots in factory 1 (estimated exposure in 1960-9 was 2480 µg.m -3 ). Highest concentrations of TMA were estimated to have occurred among the ink mixers in factory 2 from 1979 to 1986 (554 µg.m -3 ). Exposure in most other job titles was thought to be fairly constant over time for PA, TMA, and MA. Conclusions-Exposure to acid anhydride at these factories has fallen during the period covered by the study. However, it is estimated that in only one job in factory 2 did past exposure to acid anhydride exceed the current occupational exposure standard. Accuracy of the estimated exposure is limited by a paucity of reliable past exposure data. (Occup Environ Med 1998;55:692-696)

Environmental Science & Technology, 2014

Phthalate emission from vinyl floorings was measured in specially designed stainless steel chambers. Phthalate concentrations increased and reached steady state after 2 to 5 days for all experiments. By having a high ratio of emission surface to sorption surface, avoiding mass loss of phthalates onto sampling pathways, and improving air mixing inside the chamber, the time to reach steady state was significantly reduced, compared to previous studies (1 to 5 months). An innovative approach was developed to determine y 0 , the gas-phase concentration of phthalates in equilibrium with the material phase, which is the key parameter controlling phthalate emissions. Target phthalate material-phase concentration (C 0 ) and vapor pressure (V p ) were explicitly measured and found to have great influences on the y 0 value. For low phthalate concentrations in materials, a simple partitioning mechanism may linearly relate y 0 and C 0 , but cannot be evoked for high-weight phthalate percentages. In addition, the sorption kinetics and adsorption isotherm of phthalates on stainless steel chamber surfaces were determined experimentally. Independently measured or calculated parameters were used to validate a semivolatile organic compounds (SVOCs) emission model, with excellent agreement between model predictions and the observed chamber concentrations in gas and stainless steel phases. With the knowledge of y 0 and emission mechanisms, human exposure to phthalates from tested floorings was assessed; the levels were comparable to previous studies. This work developed a rapid, novel method to measure phthalate emissions; emission measurement results can be connected to exposure assessment and help health professionals estimate screening-level exposures associated with SVOCs and conduct risk-based prioritization for SVOC chemicals of concern.

The Journal of Organic Chemistry, 1951

Acta Chimica Slovenica

Polyisothianaphthene can be synthesized by reaction of phthalic anhydride with P4S10. To make the reaction economically, as well as ecologically acceptable it was necesary to increase the yield of PITN. Therefore, the influence of reaction parameters such as reaction time, quantity of xylene and catalyst were investigated. Changing these parameters a yield of 85% was achieved what is almost double the value achieved in previous experiments.

International Journal of Advances in Mechanical & Automobile Engineering, 2016

Iran is one of the main producers and consumers of plasticizers in the Middle East and Asia, but due to imposed sanctions, unfortunately Iran was deprived from the research and development in this industry. As a result, this has caused continuing the production of harmful plasticizers in Iran. In addition to the destruction and threatening of environment, these plasticizers can also affect the human health. One of the safe and environmentally friendly plasticizers is "Dioctyl Terephthalate" which was recommended by the World Health Organization (WHO), the Food and Drug Administration of the United States of America (FDA) and the European Union (EU). In this paper, I hope, with accurate reviews of the dimension of the economic, financial and market study of this product, to take a small step in manufacturing and replacing this product with current plasticizers.

Background: This work reports the determination of the levels of phthalate esters (dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), diethyl hexyl phthalate (DEHP)) and metals (lead, cadmium, manganese, zinc, iron, calcium) in composite soil samples. The soil samples were collected randomly within the Muledane open dump, Thohoyandou, Limpopo province, South Africa. Control samples were collected about 200 m away from the open dump. The phthalate esters were separated and determined by capillary gas chromatography with a flame ionization detector, whilst the metals were determined by atomic absorption spectrophotometry. Open dump values for the phthalate esters and metals to be generally higher in comparison to control samples for DMP, DEP, DBP and DEHP -the mean values calculated were 0.31 ± 0.12, 0.21 ± 0.05, 0.30 ± 0.07, and 0.03 ± 0.01 mg/kg, respectively, for the open dump soil samples. Nonetheless, the mean open dump values for lead, cadmium, manganese, zinc, iron and calcium were 0.07 ± 0.04, 0.003 ± 0.001, 5.02 ± 1.92, 0.31 ± 0.02, 11.62 ± 9.48 and 0.12 ± 0.13 mg/ kg, respectively. The results were compared statistically. Our results revealed that the discarding of wastes into the open dump is a potential source of soil contamination in the immediate vicinity and beyond, via dispersal. Increased levels of phthalate esters and metals in the soil pose a risk to public health, plants and animals. Sustained monitoring of these contaminants is recommended, in addition to upgrading the facility to a landfill. The dumping of waste on soils has been found to increase their phthalate esters and metals concentrations . Soil contaminants may be divided into two groups: organic contaminants, which contain carbon, and inor-ganic contaminants, which do not contain carbon . The organic contaminants of greatest concern are industrial in origin, and include agricultural pesticides and non-pesticide compounds like phthalate esters; whereas most