The Value-added Upgrading of Extractives

Transcription

1 The Value-added Upgrading of Extractives PhD Student: M. Sc. Mikhail Golets* Supervisor: Industry mentors: Prof. Jyri-Pekka Mikkola Dr. Hans Grundberg Dr. David Bloomberg Academic co-supervisors: Dr. William Larsson, Dr. Ajaikumar Samikannu *Technical Chemistry, Department of Chemistry, Chemical-Biological Center, Umeå University, SE-90187, Umeå, Sweden

2 Contents: 1.Project background 2.Materials and methods 3.Acetoxylation of α-pinene 4.Acetoxylation of Kraft turpentine 5.Isomerization of α-pinene to ρ-cymene 6.Oxidation of α-pinene 7.Isomeriasation of α-pinene oxide

3 Project background: Wood raw materials concurrency WEAK 0 Weighted average mill capacity, t/a Weighted average technical age 13 years Weighted average capacity t/a Russia West Canada USA South Africa Technical age, years STRONG Indonesia Brazil Finland Sweden Chile Korea Thailand France Spain Belgium Taiwan Portugal Benefits of eucalyptus usage: Fast growth (7-8 years) Higher cellulose content than birch higher pulp yield Good stiffness Excellent opacity Smoothness High porosity improved printability Benefits of birch usage: Long fiber raw material better pulp bonding ability and strength Pulp refines quickly Source: Prof. Kai Henrikkson, Chemical Pulping Technology, course lectures, Lappeenranta University of Technology, Lappeenranta, Finland.

4 Project background: Petroleum related problems 1. Greenhouse gas emissions There is a growing concern about emissions оf greenhouse gases and security оf supply connected tо the use оf fossil oil fоr transportation and as a feedstock fоr the chemical industry 2. Worldwide depletion of petrochemicals Source:

5 Project background: Sideways streams of the forest industry Оne оf the tоday under-utilized fractiоns available frоm Pulp and Paper and Biorefinery рrоcesses cоmрrises extractives. These fractions are typically burned to energy in the recovery boilers although many other value-added uses have been envisioned throughout the years α-pinene - One of the most widely occur terpene - Substantial part of industrial turpentine - Cheap and well studied for various applications: fragrances, pharmaceuticals, varnishes and dyes, transportation and aviation fuels -Huge potential for research -Price: 1,9 USD/kg for technical purity Source: Prof. Kai Henrikkson, Chemical Pulping Technology, course lectures, Lappeenranta University of Technology, Lappeenranta, Finland.

6 Specific goals of the project 1. Оxidatiоn reactiоns оf р-cymene (and analоgues) tо mоre valuable chemical рrоducts, such as tereрhtalic acid. 2. Isоmerizatiоn - hydrоgenatiоn/dehydrоgenatiоn reactiоns оf terрenes tо added-value рrоducts (heterоgeneоus gоld catalysts ) 3. Integrated оxidatiоn оf р-cymоl tо cymоl hydrорerоxide and further tо e.g. рhenоl and acetоne 4. Ultimately, uрgrading оf extractives tо renewable chemicals, transроrtatiоn and aviatiоn fuels (zeоlites, iоnexchange resins, ionic liquids) 5. Acetoxylation of terpenes to terpene acetates (fragrance compounds)

7 Materials and methods Solvents: acetic acid acetonitrile hexane acetone Equipment: PARR reactor Flow-through reactor GC GCMS Catalyst characterization Reactants: α-pinene turpentine extractive containing wood fines Catalysts: commercial and self-prepared Additions: terpene standards 99.9% purity

8 Acetoxylation of α-pinene: Background α-terpinyl acetate - Valuable monoterpene ester - Fragrance in soaps and perfumes - Excellent alkali stability - Conventionally produced via α-pinene treatment with mineral acids, followed by etherification of the obtained α-terpineol - Challenges with conventional ways: equipment corrosion, large catalyst load, serious environmental pollution and nonrecyclability of a catalyst Bornyl acetate - Important component for fragrance industry - Used for soaps, bath products and air fresheners - Alternatively, this chemical is an intermediate for camphor production Additionally, there could be a possibility for the straight utilization of the whole terpene acetates mixture

9 Acetoxylation of α-pinene: Background, Catalyst Ion-exchange resin catalyst An insoluble matrix, normally in the form of small (1 2 mm diameter) beads Has highly developed structure of pores on the surface of which are sites with easily trapped and released ions Widely used in different separation, purification, and decontamination processes We used the catalyst with strongly acidic type of functional groups (typically, sulfonic acid groups, e.g. sodium polystyrene sulfonate or polyamps) High thermal stability. Excellent kinetics, high stability and lifetime Amberlyst 70 Physical form: Spherical beads Ionic form as shipped: Hydrogen Surface area: 36 m 2 /g Average pore diameter: 220Å Concentration of acid sites: 2.55 eq/kg

10 Acetoxylation of α-pinene: Conversion The conversion was always high throughout the experimental matrix Was rapid at the elevated temperatures Temperatures below 75 C were found to be too low and resulted in a significant drop in conversion over time Symbols: ( ) 100 C, 10 bars, N 2, cat; ( ) 100 C, 10 bars, N 2, no cat; (+) 75 C, 10 bars, N 2, cat; ( ) 125 C, 10 bars, N 2, cat; ( ) 100 C, 20 bars, H 2, cat; ( ) 100 C, 20 bars, O 2, cat; ( )100 C, 20 bars, O 2, no cat; ( ) 100 C, 20 bars, O 2, no cat, 5 wt % ethyl acetate/95 wt % acetic acid; ( )100 C, 20 bars, O 2, cat, 5 wt % toluene/95 wt % acetic acid; (X) 100 C, 20 bars, O, cat, 95% aqueous acetic acid. A pressure lower than 10 bar led to poor conversion, whereas higher pressure accelerated the conversion

11 Acetoxylation of α-pinene: Yields Symbols: ( ) 100 C, 20 bars, O 2, cat; ( )100 C, 20 bars, O 2, no cat; ( ) 100 C, 20 bars, O 2, no cat, 5 wt % ethyl acetate/95 wt % acetic acid; ( )100 C, 20 bars, O 2, cat, 5 wt % toluene/95 wt % acetic acid; (X) 100 C, 20 bars, O 2, cat, 95% aqueous acetic acid.

12 Acetoxylation of α-pinene: Observations Catalyst: the number of acid cites porosity, surface area and pore volume are decreased dramatically; Reaction network was proposed: -pinyl and terpinyl ions are responsible for the reaction pathways; -in addition to the ring-opening reaction, two ring-enlarging reactions are also possible; Reaction products: -both heterogeneously- and solvent-catalyzed reactions were successful when the optimized reaction conditions were applied;

13 Acetoxylation of α-pinene: Observations C mol/dm time h Arrhenius-type temperature dependence: Strong for bornyl acetate, weak for limonene and α-terpinyl acetate; Kinetic modeling: the experimental data was fitted with a kinetic model implemented in the ModEst software;

14 Acetoxylation of α-pinene: Conclusions The one-stage process for α-pinene liquid-phase acetoxylated transformation to valueadded products was proposed under catalytic and solvent-catalyzed modes. A typical product mixture in the solvent-catalyzed reaction contained 28 wt% of α-terpinyl acetate, 30 wt% of other terpene acetates, whereas 30 wt% of bornyl acetate and 31 wt% of limonene, respectively, were obtained in the catalytic process. References M. Golets, S. Ajaikumar, D. Blomberg, H. Grundberg, J. Wärnå, T. Salmi, J.-P. Mikkola, Liquid phase acetoxylation of α-pinene over Amberlyst-70 ion-exchange resin, App Catal A: Gen (2012) M. Golets, S. Ajaikumar, W. Larsson, D. Blomberg, H. Grundberg, J. Wärnå, T. Salmi, J.- P. Mikkola, A Kinetic Study of the Liquid Phase Acetoxylation of α-pinene, Top Catal (2012) 55:

15 Study II: Acetoxylation of Kraft turpentine: Background Iggesund Mill in Sweden is one of the most advanced, fully integrated pulp and paperboard mills in the world. The products are used for the highest quality graphics products and packaging. Swedish pulp and paper industry is facing a future with increased competition from manufacturers with access to faster-growing raw materials, cheaper labour and more modern mills. To survive and stay competitive, investments in more efficient production could be one option. Iggesund Mill facts Raw material: Softwood and hardwood pulpwood. Process: Sulphate pulp. Products: Solid bleached board, plastic-coated paperboard and sulphate pulp. Production capacity: tones/year

16 Study II: Acetoxylation of mechanical turpentine: Observations α- and β-pinenes demonstrated similar behavior in terms of conversion and selectivity About 30 % of limonene was still unconvertible The average conversion was 60 % Large amount of by-products was formed because of the initial presence of limonene and impurity of the turpentine Possible solutions: 1.Limonene separation 2.Two stage process 3.Pinenes separation

17 Study III: α-pinene isomerisation to ρ-cymene ρ-cymene: Could be produced from α-pinene or turpentine; Conventionally produced via the alkylation of toluene with propene or 2- propanol Oxidation products: - ρ-isopropyl benzyl alcohol and isopropyl benzaldehyde are used in perfumery; -ρ-cresol antioxidant compound, solvent, disinfectant; - terephtalic acid precursor to PET (plastics), filler for smoke grenades.

18 Study III: α-pinene isomerisation to ρ-cymene: Results α-pinene turpentine

19 Study III: α-pinene isomerisation to ρ-cymene: Results

20 Study III: α-pinene isomerisation to ρ-cymene: Results TEM images of (a) Si-SBA-15, (b) TiO2/SBA-15, (c) Au TiO2/SBA-15 (DP) and (d) AuNi TiO2/SBA-15 (IM).

21 Study III: α-pinene isomerisation to ρ-cymene: Reaction mechanism

22 Study III: α-pinene isomerisation to ρ-cymene: Catalyst reuse The primary reason for deactivation was the coking of the catalyst (supported by the XPS and nitrogen physisorption measurements) Nitrogen physisorption Catalyst S BET, m 2 /g Pore size, nm Pore volume, cm 3 /g Fresh Spent Recovered

23 Study III: α-pinene isomerisation to ρ-cymene: Kinetic modeling Reference: S. Ajaikumar, M. Golets, W. Larsson, A. Shchukarev, K. Kordas, A.-R. Leino, J.-P. Mikkola, Micropor Mesopor Mat 173 (2013)

24 Study IV: Oxidation of α-pinene: Background and observations Targeted products α-pinene conversion Non-catalytic reaction at 90 C did not caused any conversion, however the conversion was beneficial at 110 C; Catalytic reaction was more successful at low temperatures; The optimal process parameters were evaluated as: 90 C, 10 bar O 2, 24 h, 0.15 g of catalyst.

25 Study IV: Oxidation of α-pinene : Observations Pinene oxide Verbenone In general, the verbenone formation was favored by the non-catalytic reaction. The elevated temperature could be an explanation for the substantial verbenone concentration; By the catalytic reaction the α-pinene oxide was formed; Optimal catalyst allow to reach the optimal concentration of both valuable products.

26 Study V: Isomerization of α-pinene oxide: Observations Targeted products pinocarveol α-campholenal myrthanal α-pinene oxide was very reactive, that is why we used low temperatures and pressures; The catalyst with high acidity was beneficial; The catalytic factor was crucial; Valuable mixture of fragrances was obtained.

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