Preliminary Design of Semi-Batch Reactor for Synthesis 1,3-Dichloro-2-Propanol Using Aspen Plus

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1 Preliminry Design of Semi-Btch Rector for Synthesis 1,3-Dichloro-2-Propnol Using Aspen Plus Robih Yunus Herliti, A.S. Intn & Z.Z.Abidin Deprtment of Chemicl nd Environmentl Engineering, Fculty of Engineering Universiti Putr Mlysi, Serdng 43400, Selngor, Mlysi Tel E-mil: Dzulkefly Kung Deprtment of Chemistry, Fculty of Science Universiti Putr Mlysi, Serdng 43400, Selngor, Mlysi Abstrct Glycerin is key byproduct from the biodiesel production process. Due to the rpid growth in biodiesel production, the mrket hs been flooded with the crude nturl glycerin. This crude glycerin (glycerol) hs very low vlue becuse of its impurities, nd consequently, gret interest hs emerged in the development of technology for lterntive uses of glycerol. Among the vrious possibilities, technology to convert glycerol to 1,3-dichloro-2-propnol hs cught our ttention. This compound cn be subsequently converted into epichlorohydrin, which is n importnt intermedite in the production of epoxy resins. 1,3-dichloro-2-propnol is currently being synthesized from propylene vi llyl chloride route. However, our technology uses crude nturl glycerin, the byproduct of biodiesel production plnt, s the strting mteril nd hydrochloric cid s the regent. The present pper discusses the simultion work on the semi-btch rector for the production of 1,3-dichloro-2-propnol using ASPEN PLUS. The simultion results were then compred with the experimentl dt. Keywords: Aspen plus, Dichloropropnol, Epichlorohydrin, Semi-btch, Design 1. Introduction Biodiesel s n lterntive, environmentlly friendly, nd renewble energy hs been produced on lrge scle. However one of the min problems in the production of biodiesel is the formtion of significntly mount of glycerol (10 wt%) s by-product (McCoy, 2006; Zheng, Chen, & Shen, 2008). This hs resulted in the over supply of glycerol in the industril mrket nd decrese the commercil vlue of glycerol. This scenrio hs ttrcted ttention from mny reserchers to develop lterntive routes to utilize crude glycerol in the production of useful intermedites or finl products. One of the promising methods to convert glycerol to high-vlue chemicls is the chlorintion rection for prepring 1,3-dichloro-2-propnol or α, -Dichlorohydrin (α, -DCH), which is the n importnt intermedite in the process for synthesizing epichlorohydrin (Krfft, Gilbeu, Blthsrt, & Pgnin, 2008; Kubicek, 2005; M, Zhu, Yun, & Yue, 2007; Sino et l., 2006; Tesser, Sntcesri, Di Serio, Di Nuzzi, & Findr, 2007). Since this compound is highly toxic, hrmful if inhled, nd reported s cusing cncer, this compound must be hndled with cre (Giri, 1997). Tesser et l hd crried out chlorintion rections experimentlly for prepring α, -DCH from glycerol nd gseous hydrochloric cid. Their experiment focused on the determintion of the rection kinetics. The rection ws performed in the presence of mlonic cid, s ctlyst, nd the temperture rnge ws set t -120 o C. The HCL flow rte, glycerol loded, nd ctlyst concentrtion were kept constnt t 24 g/min, 200 g, nd 8% (mol/mol) respectively. Bsed on the literture, the HCL flow rte nd ctlyst concentrtion hve mrked effects on the rection selectivity of the chlorintion rection but the extent of the effect hs not been reported (F.Kstnek, J.Zhrdnik, J.Krtochvil, & J.Cermk., 1993). Therefore, investigting the effect of HCL flow rte nd ctlyst concentrtion on the preprtion of α, -DCH would become the initil step tken in this study. Consequently, the im of this pper is to present the simultion results obtined from Aspen Plus simultor softwre crried out on the semi-btch stirred tnk rector by considering the effects of both HCL flow rte nd ctlyst concentrtion on rection selectivity nd yield for α, -DCH. The rector block utilized in the simultion ws RBtch which is suitble for semi-btch rector process (AspenTech., 1999) 196 ISSN E-ISSN

2 2. Modeling Approch 2.1. Chemicl Rections nd Kinetic Prmeters Tesser et l. (2007) hve reported tht the overll rection scheme for prepring α, -DCH, strting from glycerol nd hydrochloric cid, is s follows: CH 2 OH CH 2 Cl CH OH +2HCl CH OH + 2H 2 O CH 2 OH CH 2 Cl (1) Glycerol 1,3-dichloro-2-propnol This rection strts with the chlorintion of the glycerol, which mostly forms -monochlorohydrin ( -MCH) nd wter, with smll quntity of β-monochlorohydrin (β-mch), followed by second chlorintion from which the required product, α, -DCH ws minly obtined nd very smll mounts of α,β-dch. Reltion 1 cn be broken down into four distinct rections, which re s follows: k 1 Glycerol + HCl C 3 H 7 ClO 2 + H 2 O (2) k -1 k 2 Glycerol + HCl C 3 H 7 ClO 2 + H 2 O (3) k 3 C 3 H 7 ClO 2 +HCl C 3 H 6 ClO + H 2 O (4) k -3 DCH k C 3 H 7 ClO 2 +HCl 4 C 3 H 6 ClO + H 2 O (5) The kinetic prmeters of the rections re shown in Tble 1 (Tesser,2007). 2.2 Aspen plus Simultion Tble 2 shows the rector chrcteristic nd feed mterils used in the Aspen Plus simultion. In this work, both prmeters HCL flow rte nd ctlyst concentrtion (% by moles of glycerol loded into the rector), were vried s presented in Tble 2. The simultion nlyzed the effects of the prmeters mentioned bove on selectivity nd yield of rection. The following equtions were used for selectivity nd yield clcultion (Felder & W, 2004): selectivity for, DCH moles of, DCH produced totl moles of - MCH, - MCH, nd, - DCH produced moles of, DCH produced Yield for, DCH moles of glycerol fed 3. Simultion Result nd Model Vlidtion 3.1 Model Vlidtion In order to vlidte the proposed model, experimentl dt from glycerol chlorintion in lb-scle semi-btch stirred tnk rector reported by Tesser et.l (2007) ws used to vlidte the simultion. Tbles 1 nd 2 show the kinetic prmeters nd rector chrcteristics used in the simultion. The simultion results in terms of rection selectivity nd glycerol conversion re compred with the experimentl dt. The results re shown below. <Figure 1-Figure 3> Figures 1 nd 2 show the simultion results s compred to the experimentl dt for glycerol conversion nd rection selectivity t five different tempertures in the rnge of 120 o C. Simultion results nd experimentl dt for products composition versus time of the rection is shown in Figure 3. These figures show tht there is strong greement between Aspen Plus simultion results nd experimentl dt. Thus, we cn conclude tht the Published by Cndin Center of Science nd Eduction 197

3 Aspen Plus simultion cn indeed be used in our study to guide us in the nlysis of the performnce of the chlorintion rection using the crude glycerol. <Figure 4> Furthermore, severl simultion runs hd lso been crried out in order to investigte effect of HCL flow rte nd ctlyst concentrtion on selectivity nd yield for α, -DCH preprtion. Selectivity nd yield of α, -DCH decresed over the HCL flow rte rnge from 4 to 24 g/min s shown in Figure 4. It is in good greement compred qulittively to dt from the literture. Rose (1981) reported tht the gs feed rte to the stirred tnk should be not more thn wht is clled flood point of the impeller in order to prevent spinning of gittor in bubble of the gs tht hve mrked on the rection (L.M.Rose, 1981). In contrst, ctlyst concentrtion does not significntly ffect the selectivity nd yield for α, -DCH preprtion s depicted in Figure 5. <Figure 5> 4. Conclusion In the present pper, simultion study ws crried out on the α, -DCH preprtion in semi btch stirred tnk rector (SBSTR) using the Aspen Plus simultion softwre. The resulting simultion results were used to predict the performnce of SBSTR in terms of selectivity nd yield. Effect of both HCL flow rte nd ctlyst concentrtion hd lso been investigted. While lower HCL flow rte improves the chlorintion process on both the selectivity nd yield of α, -DCH, the ctlyst concentrtion does not hve significnt effect on the process. The findings from these simultion results cn be used in our experimentl work to develop the technology to convert crude glycerol to 1,3-dichloro-2-propnol nd subsequently into epichlorohydrin, which is n importnt intermedite in the production of epoxy resins. Acknowledgement This project is supported by ScienceFund grnt funded by Ministery of Science nd Innovtion Mlysi. This finncil ssistnce is grtefully cknowledged. References AspenTech. (1999). Introduction to ASPEN PLUS, Bsed on Aspen Plus F.Kstnek, J.Zhrdnik, J.Krtochvil, & J.Cermk. (1993). Chemicl Rectors for Gs-Liquid System (1st ed.). New York: Czech Republic. Felder, R. M., & W, R. R. (2004). Elementry Principles of Chemicl Processes. New York: Wiley. Giri, A. K. (1997). Genetic toxicology of epichlorohydrin: Review. Muttion Reserch, 386: Krfft, P., Gilbeu, P., Blthsrt, D., & Pgnin, M. (2008). Mnufcturing dichloropropnol involves recting glycerol with pressurized hydrogen chloride, followed by subjecting to tretment for reducing weight rtio between hydrogen chloride nd wter, nd/or between the wter nd dichloropropnol: WO Kubicek. (2005). Method of Prepring Dichloropropnol From Glycerol. World Intellectul Property Orgniztion US: WO 2005/ A1 L.M.Rose. (1981). Chemicl Rector Design in Prctice. New York: Amsterdm. M, L., Zhu, J. W., Yun, X. Q., & Yue, Q. (2007). Synthesis of epichlorohydrin from dichloropropnols: Kinetic spects of the process. Chemicl Engineering Reserch & Design, 85(A12): McCoy, M. (2006). Bussiness Glycerin Surplus: Plnts re closing, nd new uses for the chemicl re being found. 84(6). Sino, D., Sntcesri, E., Findr, V., Tesser, R., Di Nuzzi, G., Di Serio, M., & Nstsi, M. (2006). Continuous regioselective process for the production of 1,3-dichloro-2-propnol from glycerin nd hydrochloric cid in the presence of orgnic crboxylic cid ctlyst., World Orgniztion Ptent. Tesser, R., Sntcesri, E., Di Serio, G., Di Nuzzi, G., & Findr, V. (2007). Kinetics of Glycerol Chlorintion with Hydrochlorc Acid. Ind. Eng. Chem. Res, 46: Zheng, Y. G., Chen, X. L., & Shen, Y. C. (2008). Commodity Chemicls Derived from Glycerol, n Importnt Biorefinery Feedstock. Chemicl Reviews, 108(12): ISSN E-ISSN

4 Tble 1. Kinetic prmeters T ( o C) K 1 k 2 K 3 K 4 K 1 K ± ±41 714±227 8± ± ± ±407 26± ± ± ±685 31± Kinetic constnt re expressed in cm 3 /(mol min) Tbel 2. Set up Prmeters used in the Simultion Rector Block Bse Method Input Vrible Temperture ( o C) Pressure (br) Chemicl rections Kinetics rte constnt RBtch Wilson Rection 2 to 5 From Tble 1 Feed of Rector HCL flow rte (g/min) Concentrtion of mlonic cid ctlyst (%) 4, 8, 12, 16, 20, 24 2,4,6,8, Glycerol Conversion (%) exp sim Temperture oc Figure 1. Effect of Temperture on Glycerol conversion. Glycerol loded: 200g; HCL flow rte: 24 g/min; Ctlyst concentrtion: 8% by moles; rection time: 2.5 h Published by Cndin Center of Science nd Eduction 199

5 60 50 selectivity (%) exp sim Temperture oc Figure 2. Effect of Temperture on rection selectivity. Glycerol loded: 200g; HCL flow rte: 24 g/min; Ctlyst concentrtion: 8% by moles; rection time: 2.5 h 100 mole frctions t (min) glycerol α-monochlorohydrin β-monochlorohydrin 1,3-dichloro-2-propnol 2,3-dichloro-1-propnol glycerol (sim) α-monochlorohydrin (sim) β-monochlorohydrin (sim) 1,3-dichloro-2-propnol (sim) 2,3-dichloro-1-propnol (sim) Figure 3. Evolution in time of Products composition. Glycerol loded: 200g; HCL flow rte: 24g/min; Ctlyst concentrtion: 8% by moles; rection temperture: 110 o C 200 ISSN E-ISSN

6 selectivity (%) yield (%) HCL Flow Rte (g/min) Figure 4. Effect of HCL flow rte on selectivity nd yield predicted by the simultion. Glycerol loded: 200g; Ctlyst concentrtion: 8% by moles; rection temperture: 110 o C; rection time: 2.5 h 73 selectivity yield selectivity (%) yield (%) ctlyst concentrtion (%) 72 Figure 5. Effect of ctlyst concentrtion on selectivity nd yield predicted by the simultion. Glycerol loded: 200g; HCL flow rte: 4 g/min; rection temperture: 110 o C; rection time: 2.5 h Published by Cndin Center of Science nd Eduction 201