Liquid phase methanol process

Air Products, Liquid-Phase Methanol Process Development Unit Instaliation, Operation and Support Studies Topical Report Task 10 Liquid Entrained Operations in the La Porte PDU,... 

J.J. Lewnard, P.R. Stepanoff and P. Rao, Recent Laboratory Activities Towards Developing the Liquid-Phase Methanol Process , 6th Annual Department of Energy Liquefaction Contractor s Meeting, Monroeville, PA, December 2-4, 1966... 

Air Products and Chemicals, Inc. Liquid-Entrained Catalyst Operations at LaPorte Pilot Plant for Liquid-Phase Methanol Process, 1984-1985, Final report to U.S. Department of Energy, AP-5049 Research Project 317-3, February 1987 1-19. 

Commercial-Scale Demonstration of the Liquid Phase Methanol Process -Project Performance Summary, Air Products Liquid Phase Conversion Company, June 2004. 

In order to avoid some of the current limitations of the vapor phase methanol synthesis, EPRI and Chem. Systems are developing a liquid phase methanol process (44,45). 

As a case study an acetic acid process has been given. Acetic acid is produced by a liquid-phase methanol carbonylation. Acetic acid is formed by the reaction between methanol and carbon monoxide which is catalysed by rhodium iodocarbonyl catalyst. The process diagram is shown in Figure 7. 

Liquid-phase methanol hydrochlorination process, 16 322 Liquid-phase oxidation of re-butane, 13 697... 

In simple experiments, particulate silica-supported CSPs having various cin-chonan carbamate selectors immobilized to the surface were employed in an enantioselective liquid-solid batch extraction process for the enantioselective enrichment of the weak binding enantiomer of amino acid derivatives in the liquid phase (methanol-0.1M ammonium acetate buffer pH 6) and the stronger binding enantiomer in the solid phase [64]. For example, when a CSP with the 6>-9-(tcrt-butylcarbamoyl)-6 -neopentoxy-cinchonidine selector was employed at an about 10-fold molar excess as related to the DNB-Leu selectand which was dissolved as a racemate in the liquid phase specified earlier, an enantiomeric excess of 89% could be measured in the supernatant after a single extraction step (i.e., a single equilibration step). This corresponds to an enantioselectivity factor of 17.7 (a-value in HPLC amounted to 31.7). Such a batch extraction method could serve as enrichment technique in hybrid processes such as in combination with, for example, crystallization. In the presented study, it was however used for screening of the enantiomer separation power of a series of CSPs. 

In industrial practice, three-phase catalytic reactors are often used, with gases like such as H2, H2O, NH3 or O2 as reactants. The process can be classified on the basis of these gases as hydrogenation, hydration, amination, oxidation, etc [3]. Among these processes, hydrogenation is by far the most important multiphase catalytic reaction. Recently, liquid- -phase methanol synthesis and the Fischer-Tropsch process were commercialized respectively... 

Cybulski et al. [39] have studied the performance of a commercial-scale monolith reactor for liquid-phase methanol synthesis by computer simulations. The authors developed a mathematical model of the monolith reactor and investigated the influence of several design parameters for the actual process. Optimal process conditions were derived for the three-phase methanol synthesis. The optimum catalyst thickness for the monolith was found to be of the same order as the particle size for negligible intraparticle diffusion (50-75 p.m). Recirculation of the solvent with decompression was shown to result in higher CO conversion. It was concluded that the performance of a monolith reactor is fully commensurable with slurry columns, autoclaves, and trickle-bed reactors. 

This work focuses on the investigation of the stability of catalytic activity in the liquid phase methanol synthesis process. Novel catalysts with a long-term stability have been developed by the addition of hydrophobic materials. The addition of hydrophobic materials were effective for slowing down the crystallite size growth and inhibition of deactivation of catalyst as compared with the original catalyst without modification. 

Methanol synthesis from CO2 and H2 has received much attention as one of the most promising processes to convert C02 into chemicals. Gas-phase methanol synthesis process should recycle a large quantity of unconverted gas and furthermore the single pass conversion is limited by the large heat release in the reaction. Liquid-phase methanol synthesis in solvent has received considerable attention, since temperature control is much easier in the liquid phase than in the gas phase. 

Several types of reactors have been proposed such as the liquid entrained reactor(l) and the Trickle bed reactor(2). The authors have been studying a liquid-phase methanol synthesis process in order to develop a new technology as an alternative for a gas-phase process, and reported that a new process employing liquid-liquid separation of the products from the solvent has several advantages in practical methanol synthesis(3). 

The catalysts with a long-term stability for the liquid-phase methanol synthesis process have been developed. The addition of hydrophobic materials to the catalyst could suppress the sintering of Cu particles in the catalyst and then result in a long-term stability of the catalyst. The modification of Cu/ZnO-based catalyst by the hydrophobic treatment is very uscfiil for improving a long-term stability of the catalyst for the liquid-phase methanol synthesis from C02 and H2. 

With continuing refinements to the rhodium-catalyzed, liquid-phase, methanol carbonylation technology (see Section 2.1.2.1.5), this industrial process will remain the most competitive route to acetic acid, well into the 21 st century. 

EniChem set up a project aimed at the development of a nonphosgene synthesis of DMC for large volume usage as a result, a new industrial process was established, based on a liquid-phase methanol oxidative carbonylation in the presence of copper chlorides as catalysts. This catalytic system was highly effective in DMC production the reaction was carried out by feeding at the same time methanol, carbon monoxide, and oxygen to the suspension of the catalyst in a mixture of water, methanol, and DMC and recovering DMC by distillation after the catalyst separation. Besides, the process... 

Vijayaraghavan, P. Kulik, C.J. Lee, S. Modelling of a liquid entrained reactor for liquid phase methanol synthesis process. Fuel Sci. Technol. Int. 1992, 10 (9), 1501-1521. 

Uztiirk S, Shah YT, Deckwer W-D (1988) Comparison of Gas and Liquid Phase Methanol Synthesis Processes. Chem Eng J 37 177-192... 

Heydorn, E.C. Street, B.T. Sarkus, T.A. Komosky, R.M. Miller, C.L. Clean Coal Technology, DOE Topical Report Commercial-Scale Demonstration of the Liquid Phase Methanol (LPMEOH ) Process., April, 1999, Number 11. 

The ICI patents (ref. 20) describe the use of intermetallics (similar to those in Tabel 2 above) in liquid-phase methanol synthesis. The reaction was conducted at 70°C and 5 MPa using a syngas of 67 /33 CO which was contacted with a sample of ground catalyst suspended in 10 times its mass of octane. Although no details of activity are given it is claimed that high methanol yields were produced under those conditions. Therefore, the copper-based intermetallic catalysts may have application in the Chem Systems process. 

In addition, new and novel methanol production processes are being developed, and the patent literature is very active. Many of the contributions to this conference describe the forefront of these technologies. Liquid-phase methanol synthesis via the Chem Systems process has been demonstrated in a large semi-works unit since 1984 (ref. 5). And a new methanol production process which uses air partial oxidation has been proposed by Brookhaven National Laboratory (ref. 6). 

In each experiment, the substrate (40 g), catalyst (0.2 g, dry basis), aqueous ammonia (24 ml), and methanol were charged to the RCl reactor. The mixture was stirred at 16(X) rpm under Nj at the reaction temperature to dissolve the substrate. The substrate was fully soluble in the solvent under these conditions. To initiate the hydrogenation reaction, Nj was rapidly evacuated by a mechanical pump, followed by pressurizing the reactor to 40 psig H,. This evacuation-and-fiU procedure was conducted with the agitation speed at 1600 rpm to ensure rapid and complete degassing of the inert gas from, and rapid incorporation of Hj into the liquid phase. The process usually took < 10 s. 

In 1975, Chem Systems developed the liquid phase methanol (LPMeOH) process which is based on the low pressure synthesis technology except that the new process is carried out in an inert oil phase [79], The catalytic system used is Cu/Zn0/Al203, that is modified for slurry operation (i.e., attrition resistant, finely powdered, and leaching resistant). The S3.85 and S3.86 catalysts of BASF and EPJ-19 and EPJ-25 catalysts of United Catalysts Inc. were developed for this process [14,19]. The process has been tested for commercial feasibility at a demonstration scale by Air Products and Chemicals, Inc [79]. 

Lee, S., Research support for liquid phase methanol synthesis process development, Electric Power Research Report. AP-4429, pp. 1-312, Palo Alto, CA, February 1986. 

Ko. M.K. Mass Transfer Analysis of the Liquid Phase methanol Synthesis process, Ph.D. dissertation. University of Skron, Akron, OH, 1987. 

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