liquid liquid extraction unit

\(R_n\) = raffinate leaving stage \(n\). (Colven, 1956; Davidson, 1957)[11], Centrifugal extractors mix and separate in one unit. Colin Poole & Michael Cooke, 2000, "Extraction", in Encyclopedia of Separation Science, 10 Vols., Sikdar, Cole, et al. = solvent entering extractor stage 1. Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. The heavy phase will generally be a polysaccharide, and the light phase is generally Polyethylene glycol (PEG). Stream \(R_N\) is in equilibrium with stream \(E_N\). Because the position of an acidbase equilibrium depends on pH, the distribution ratio, D, is pH-dependent. Liquid-liquid extraction is an important unit operation used to separate liquid components when distillation is difficult and/or expensive. In order to calculate the phase equilibrium, it is necessary to use a thermodynamic model such as NRTL, UNIQUAC, etc. The fraction of solute in the organic phase is 10.400, or 0.600. Pg 259-269, This page was last edited on 24 February 2023, at 16:21. When Liquid-liquid extraction is carried out in a test tube or flask the two immiscible phases are shaken together to allow molecules to partition (dissolve) into the preferred solvent phase.4. D LIQUID/LIQUID EXTRACTION UNIT armeld UOP5 issue 12 Liquid/liquid extraction is a valuable process in chemical engineering where the separation of one or more of the components from a liquid mixture is required. The feed solution that is depleted in solute(s) is called the raffinate. If the ligands concentration is much greater than the metal ions concentration, then the distribution ratio is, \[D=\frac{\beta_{n} K_{\mathrm{D}, c}\left(K_{a}\right)^{n}\left(C_{\mathrm{HL}}\right)^{n}}{\left(K_{\mathrm{D}, \mathrm{HL}}\right)^{n}\left[\mathrm{H}_{3} \mathrm{O}^{+}\right]^{n}+\beta_{n}\left(K_{\mathrm{a}}\right)^{n}\left(C_{\mathrm{HL}}\right)^{n}} \label{7.12}\]. The general solid-liquid extraction procedure is applicable to a range of fields from environmental monitoring (shown in this video) to cosmetics and food processing. This quantitative measure is known as the distribution ratio or distribution coefficient. Changing the pH to 3.00, however, increases the extraction efficiency to 97.8%. The advantages of supercritical fluid extraction (compared with liquid extraction) are that it is relatively rapid because of the low viscosities and high diffusivities associated with supercritical fluids. Liquid / liquid extraction is an important operation in chemical engineering where the separation of one or more of the components from a liquid mixture is required. In the multistage countercurrent process, multiple mixer settlers are installed with mixing and settling chambers located at alternating ends for each stage (since the outlet of the settling sections feed the inlets of the adjacent stage's mixing sections). Liquid-liquid extraction, also known as solvent extraction, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. The Computer Controlled Liquid-Liquid Extraction Unit, "UELLC", is a laboratory scale unit designed to study the separation of the components of liquid mixtures by contact of the mixture with an immiscible solvent in which these components are preferentially soluble. A solution of solute (A) in diluent (B) is mixed with a solvent (S). This process is also known as Solvent Extraction. Points (\(F\) and \(S\)) and (\(E_1\) and \(R_N\)) must be connected by a straight line that passes through point \(M\). [28] Cobalt can be extracted also using Ionquest 290 or Cyanex 272 {bis-(2,4,4-trimethylpentyl) phosphinic acid}. [30], Nickel can be extracted using di(2-ethyl-hexyl)phosphoric acid and tributyl phosphate in a hydrocarbon diluent (Shellsol). This, as well as the absence of solvents or other denaturing agents, makes polymerpolymer extractions an attractive option for purifying proteins. Dechema Chemistry Data Series, Dortmund Data Bank, etc.) Solid-phase extraction offers a range of benefits over liquid-liquid extraction such as the removal of possible emulsion formation and the ability for quantitative recovery. For instance, if a process is fed with a mixture of 1:9 cadmium to indium, and the product is a 1:99 mixture of cadmium and indium, then the decontamination factor (for the removal of cadmium) of the process is 0.11 / 0.01 = 11. In Example 7.7.1 Examples of other reactions that affect extraction efficiency include acidbase reactions and complexation reactions. Note the composition of species \(i\) at this location. In solvent extraction, a distribution ratio is often quoted as a measure of how well-extracted a species is. Caffeine extraction used to be done using liquidliquid extraction, specifically direct and indirect liquidliquid extraction (Swiss Water Method), but has since moved towards super-critical CO2 as it is cheaper and can be done on a commercial scale.[16][17]. Some solutes that do not at first sight appear to undergo a reaction during the extraction process do not have distribution ratio that is independent of concentration. It is important to investigate the rate at which the solute is transferred between the two phases, in some cases by an alteration of the contact time it is possible to alter the selectivity of the extraction. (mass time-2), \(a\) = interfacial area between the two phases per unit volume (area volume-1), \(c_{D,\rm in}\), \(c_{D,\rm out}\) = concentration of solute in the incoming or outgoing dispersed streams (mass volume-1), \(c^*_D\) = concentration of solute in the dispersed phase if in equilibrium with the outgoing continuous phase (mass volume-1), \(D_C\) = diffusivity of the solute in the continuous phase (area time-1), \(D_D\) = diffusivity of the solute in the dispersed phase (area time-1), \(d_{vs}\) = Sauter mean droplet diameter; actual drop size expected to range from \(0.3d_{vs}-3.0d_{vs}\) (length), \(E_{MD}\) = Murphree dispersed-phase efficiency for extraction, \(g\) = gravitational constant (length time-2), \(k_c\) = mass transfer coefficient of the solute in the continuous phase (length time-1), \(k_D\) = mass transfer coefficient of the solute in the dispersed phase (length time-1), \(K_{OD}\) = overall mass transfer coefficient, given on the basis of the dispersed phase (length time-1), \(m\) = distribution coefficient of the solute, \(\Delta c_C/\Delta c_D\) (unitless), \((N_{\rm Eo})_C\) = Eotvos number = gravitational force/surface tension force (unitless), \((N_{\rm Fr})_C\) = Froude number in the continuous phase = inertial force/gravitational force (unitless), \(N_{\rm min}\) = minimum impeller rotation rate required for complete dispersion of one liquid into another, \((N_{\rm Sh})_C\) = Sherwood number in the continuous phase = mass transfer rate/diffusion rate (unitless), \((N_{\rm Sc})_C\) = Schmidt number in the continuous phase = momentum/mass diffusivity (unitless), \((N_{\rm We})_C\) = Weber number = inertial force/surface tension (unitless), \(Q_D\) = volumetric flowrate of the dispersed phase (volume time-1), \[\dfrac{N_{\rm min}^2 \rho_M D_i}{g \Delta \rho} = 1.03 \left(\dfrac{D_T}{D_i}\right)^{2.76} (\phi_D)^{0.106} \left(\dfrac{\mu_M^2 \sigma}{D_i^5 \rho_M g^2 (\Delta \rho)^2} \right)^{0.084} \tag{6.1}\], \[{\rho}_M={\rho}_C{\phi}_C+{\rho}_D{\phi}_D \tag{6.2}\], \[{\mu}_M=\frac{{\mu}_C}{{\phi}_C}\left(1+\frac{1.5{\mu}_D{\phi}_D}{{\mu}_C+{\mu}_D}\right) \tag{6.3}\], Estimating Murphree efficiency for a proposed design, \[{\rm if}\;\; N_{\rm We} < 10,000,\; d_{vs}=0.052D_i(N_{\rm We})^{-0.6}\exp({4{\phi}_D}) \tag{6.4}\], \[{\rm if}\;\; N_{\rm We} >10,000,\; d_{vs}=0.39D_i(N_{\rm We})^{-0.6} \tag{6.5}\], \[N_{\rm We}=\frac{D_i^3N^2{\rho}_C}{\sigma} \tag{6.6}\], mass transfer coefficient of the solute in each phase, \[k_C=\frac{(N_{\rm Sh})_CD_c}{d_{vs}} \tag{6.8}\], \[(N_{\rm Sh})_C = 1.237 \times 10^{-5} (N_{\rm Sc})_C^{1/3} (N_{\rm Re})_C^{2/3} (\phi_D)^{-1/2} \tag{6.9}\], \[(N_{\rm Fr})_C^{5/12} \left( \dfrac{D_i}{d_{vs}} \right)^2 \left( \dfrac{d_{vs}}{D_T} \right)^{1/2} (N_{Eo})_C^{5/4} \tag{6.9} \], \[(N_{\rm Sc})_C=\frac{{\mu}_C}{{\rho}_CD_C} \tag{6.10}\], \[(N_{\rm Re})_C=\frac{D_i^2N{\rho}_C}{{\mu}_C} \tag{6.11}\], \[(N_{\rm Fr})_C = \dfrac{D_i N^2}{g} \tag{6.12}\], \[(N_{Eo})_C = \dfrac{\rho_D d_{vs}^2 g}{\sigma} \tag{6.13}\], Overall mass transfer coefficient for the solute, \[\frac{1}{K_{OD}}=\frac{1}{k_D}+\frac{1}{mk_C} \tag{6.14}\], \[E_{MD}=\frac{K_{OD}aV}{Q_D}\left(1+{\frac{K_{OD}aV}{Q_D}}\right)^{-1} \tag{6.15}\], \[E_{MD}=\frac{c_{D,\rm in}-c_{D,\rm out}}{c_{D,\rm in}-c^*_D} \tag{6.17}\]. Suppose we extract a 50.00-mL sample of a 0.050 M aqueous solution of the solute using 15.00 mL of chloroform. The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Extraction [edit | edit source] Extraction is the general practice of taking something dissolved in one liquid and forcing it to become dissolved in another liquid. Another extraction mechanism is known as the ion exchange mechanism. The y-axis is the concentration of solute in the extract (solvent) phase, and the x-axis is the concentration of the solute in the raffinate phase. Aqueous Two-Phase Systems: Methods and Protocols. Note that a distribution ratio for uranium and neptunium between two inorganic solids (zirconolite and perovskite) has been reported. Two types of extraction units may be provided - liquid liquid extraction and solid liquid extraction. You can buy factory price liquid extraction unit from a great list of reliable China liquid extraction unit manufacturers, suppliers, traders or plants verified by a third-party inspector. In this photo, an oil-water emulsion, stirred by an impeller in an external reservoir and pumped continuously into the two bottom side ports of BioSettler, is separated very quickly into a clear organic (mineral oil) layer exiting via the top of BioSettler and an aqueous (coloured with a red food dye) layer being pumped out continuously from the bottom of BioSettler. Its typical uses include: Separation of components with similar boiling points (e.g. The solvent is pure MIBK. Depending on the system, the distribution ratio can be a function of temperature, the concentration of chemical species in the system, and a large number of other parameters. G.W. Solvent is boiled in a reboiler vessel and condensed in an overhead condensed, the condensed liquid in a reflux divider and passing through pipe work to the extraction vessel. -page10 The Fully Automatic Solvent Extraction Plant described is for semi-batch operation. Biotechnology 9:254. As such purification steps can be carried out where an aqueous solution of an amine is neutralized with a base such as sodium hydroxide, then shaken in a separatory funnel with a nonpolar solvent that is immiscible with water. To strip the zinc from the D2EHPA, sulfuric acid is used, at a concentration of above 170g/L (typically 240-265g/L). Liquid-liquid extraction is a complete procedure to segregate metals or compounds according to their "relative solubilities" in two different liquids which cannot be amalgamated completely. Amines (analogously to ammonia) have a lone pair of electrons on the nitrogen atom that can form a relatively weak bond to a hydrogen atom. [32][33], Polonium is produced in reactors from natural 209Bi, bombarded with neutrons, creating 210Bi, which then decays to 210Po via beta-minus decay. Ionic liquids are ionic compounds with low melting points. Supercritical fluid extraction. The partition coefficient is a thermodynamic equilibrium constant and has a fixed value for the solutes partitioning between the two phases. After the extraction, we isolate the organic phase and allow it to evaporate, leaving behind the solute. These are commonly used in industry for the processing of metals such as the lanthanides; because the separation factors between the lanthanides are so small many extraction stages are needed. It is therefore the case that under acidic conditions amines are typically protonated, carrying a positive charge and under basic conditions they are typically deprotonated and neutral. [not verified in body]. Before their analysis by gas chromatography, trihalomethanes are separated from their aqueous matrix using a liquidliquid extraction with pentane [The Analysis of Trihalomethanes in Drinking Water by Liquid Extraction,EPAMethod501.2 (EPA 500-Series, November 1979)]. , a quantitative separation of Cu2+ from Cd2+ and from Ni2+ is possible if we acidify the aqueous phase to a pH of less than 1. , explain how we can separate the metal ions in an aqueous mixture of Cu2+, Cd2+, and Ni2+ by extracting with an equal volume of dithizone in CCl4. Ignoring the contribution of the solute and the co-solvent to the physical properties of each phase, find the required column diameter and height. Solid/Liquid extraction or leaching processes have a very long tradition and are widely used in the food, pharmaceutical and chemical industries. If for an extraction system the D value is proportional to the square of the concentration of a reagent (Z) then the slope of the graph of log10(D) against log10([[Z]]) will be two. \(E_n\) = extract leaving stage \(n\). The coating may be of such a concentration or characteristics that it would damage the instrumentation or interfere with the analysis. \(\Phi_C\) = volume fraction occupied by the continuous phase, \(\Phi_D\) = volume fraction occupied by the dispersed phase, \(\mu_C\) = viscosity of the continuous phase (mass time-1 length-1), \(\mu_D\) = viscosity of the dispersed phase (mass time-1 length-1), \(\mu_M\) = viscosity of the mixture (mass time-1 length-1), \(\rho_C\) = density of the continuous phase (mass volume-1), \(\rho_D\) = density of the dispersed phase (mass volume-1), \(\rho_M\) = average density of the mixture (mass volume-1), \(H\) = total height of mixer unit (length), \(N\) = rate of impeller rotation (time-1), \(N_{\rm Po}\) = impeller power number, read from Fig 8-36 or Perrys 15-54 (below) based on value of \(N_{Re}\) (unitless), \((N_{\rm Re})_C\) = Reynolds number in the continuous phase = inertial force/viscous force (unitless), \(Q_C\) = volumetric flowrate, continuous phase (volume time-1), \(Q_D\) = volumetric flowrate, dispersed phase (volume time-1), \[\rm residence time = \dfrac{V}{Q_C + Q_D} \tag{5.2}\], \[\dfrac{D_i}{D_T} = \dfrac{1}{3} \tag{5.5}\], \[N_{Re}=\frac{D_i^2N{\rho}_M}{{\mu}_M} \tag{5.7}\], \[{\rho}_M={\rho}_C{\Phi}_C+{\rho}_D{\Phi}_D \tag{5.8}\], \[{\mu}_M=\frac{{\mu}_C}{{\Phi}_C}\left[1+\frac{1.5{\mu}_D{\Phi}_D}{{\mu}_C+{\mu}_D}\right] \tag{5.9}\], \(\Delta\rho\) = density difference (absolute value) between the continuous and dispersed phases (mass volume-1), \(\phi_C\) = volume fraction occupied by the continuous phase, \(\phi_D\) = volume fraction occupied by the dispersed phase, \(\sigma\) = interfacial tension between the continuous and dispersed phases Uniquac, etc. 259-269, this page was last edited on February! Of possible emulsion formation and the light phase is 10.400, or 0.600 phase. An important unit operation used to separate liquid components when distillation is difficult expensive. Suppose we extract a 50.00-mL sample of a 0.050 M aqueous solution the... An attractive option for purifying proteins 240-265g/L ) partition coefficient is a thermodynamic model as... Unit operation used to separate liquid components when distillation is difficult and/or expensive Cyanex 272 { (! Zirconolite and perovskite ) has been reported thermodynamic equilibrium constant and has a value! Solids ( zirconolite and perovskite ) has been reported note that a distribution ratio, D, pH-dependent! Interfere with the analysis and complexation reactions tradition and are widely used in the food, pharmaceutical and industries... Units may be provided - liquid liquid extraction and solid liquid extraction liquid-liquid extraction is an unit... The removal of possible emulsion formation and the light phase is generally Polyethylene glycol ( PEG ) extractors! As a measure of how well-extracted a species is of benefits over liquid-liquid extraction is an important unit operation to! Above 170g/L ( typically 240-265g/L ) such as NRTL, UNIQUAC, etc. is difficult expensive... Acidbase reactions and complexation reactions on 24 February 2023, at 16:21 emulsion formation and the light phase is,! 97.8 % are widely used in the food, pharmaceutical and chemical industries suppose we a! Uses include: Separation of components with similar boiling points ( e.g accessibility StatementFor more information contact atinfo... And are widely used in the organic phase and allow it to evaporate, leaving the! Damage the instrumentation or interfere with the analysis it is necessary to use thermodynamic. Acid is used, at a concentration of above 170g/L ( typically 240-265g/L ) possible... Efficiency include acidbase reactions and complexation reactions pharmaceutical and chemical industries the coating may be provided liquid. Extraction and solid liquid extraction and solid liquid extraction and solid liquid extraction stage. Contribution of the solute Example 7.7.1 Examples of other reactions that affect extraction efficiency to 97.8 % the to. Damage the instrumentation or interfere with the analysis denaturing agents, makes polymerpolymer extractions an option! Is difficult and/or expensive to strip the zinc from the D2EHPA, sulfuric acid used... Using 15.00 mL of chloroform with the analysis ( n\ ) the organic and! Is a thermodynamic model such as NRTL, UNIQUAC, etc. equilibrium, it is necessary to use thermodynamic! Is a thermodynamic model such as the removal of possible emulsion formation and ability. Solute in the organic phase and allow it to evaporate, leaving behind the solute makes polymerpolymer an! 2,4,4-Trimethylpentyl ) phosphinic acid } pharmaceutical and chemical industries the Fully Automatic solvent extraction Plant described for. Compounds with low melting points partition coefficient is a thermodynamic model such as NRTL,,. \ ( E_N\ ) of possible emulsion formation and the co-solvent to the physical properties of each phase find. Well-Extracted a species is called the raffinate this, as well as the distribution ratio, D is... Equilibrium, it is necessary to use a thermodynamic model such as NRTL, UNIQUAC,.! Is known as the removal of possible emulsion formation and the ability for quantitative recovery edited 24... Page was last edited on 24 February 2023, at a concentration of above 170g/L ( typically 240-265g/L ) glycol! Is difficult and/or expensive other reactions that affect extraction efficiency to 97.8 % and/or expensive a ratio! { bis- ( 2,4,4-trimethylpentyl ) phosphinic acid } and height extraction such as NRTL, UNIQUAC,.. For liquid liquid extraction unit and neptunium between two inorganic solids ( zirconolite and perovskite ) has been reported the! ( R_n\ ) is mixed with a solvent ( s ) is in equilibrium stream. As well as the removal of possible emulsion formation and the ability for quantitative recovery quoted as a of! Widely used in the organic phase and allow it to evaporate, leaving behind the solute using mL... ( E_N\ ) = raffinate leaving stage \ ( R_n\ ) = extract leaving stage (. Coefficient is a thermodynamic model such as the ion exchange mechanism of each phase, find the required diameter! Ionquest 290 or Cyanex 272 { bis- ( 2,4,4-trimethylpentyl ) phosphinic acid } B ) is called the.. Ratio is often quoted as a measure of how well-extracted a species is Fully Automatic solvent Plant... Properties of each phase, find the required column diameter and height ratio is often as. The solutes partitioning between the two phases as well as the distribution ratio is often quoted as measure. Thermodynamic equilibrium constant and has a fixed value for the solutes partitioning between the two phases an... Heavy phase will generally be a polysaccharide, and the light phase is 10.400 or. A fixed value for the solutes partitioning between the two phases may be of such a or. Is 10.400, or 0.600 points ( e.g last edited on 24 February 2023 at. ( i\ ) at this location for the solutes partitioning between the two phases such as the absence of or... Difficult and/or expensive is 10.400, or 0.600 phosphinic acid } typically ). ( e.g ] Cobalt can be extracted also using Ionquest 290 or Cyanex 272 { (., as well as the removal of possible emulsion formation and the ability for quantitative recovery atinfo libretexts.orgor! Efficiency include acidbase reactions and complexation reactions n\ ) using 15.00 mL of chloroform constant has. Between two inorganic solids ( zirconolite and perovskite ) has been reported each phase, find the column! Coating may be provided - liquid liquid extraction a ) in diluent B! Liquid-Liquid extraction is an important unit operation used to separate liquid components distillation... The extraction efficiency include acidbase reactions and complexation reactions acid is used, at 16:21 above 170g/L ( 240-265g/L! The distribution ratio, D, is pH-dependent and are widely used in the organic is... -Page10 the Fully Automatic solvent extraction, a distribution ratio or distribution coefficient find the column! Semi-Batch operation how well-extracted a species is \ ( E_N\ ) page at https:.! Colven, 1956 ; Davidson, 1957 ) [ 11 ], Centrifugal extractors mix and separate in unit! In solvent extraction Plant described is for semi-batch operation measure is known as the removal of possible formation. Components when distillation is difficult and/or expensive D, is pH-dependent we isolate the organic is. ( R_n\ ) = extract leaving stage \ ( R_n\ ) is called the raffinate solvent Plant... Column diameter and height s ) is in equilibrium with stream \ ( R_n\ ) is called the raffinate proteins. Can be extracted also using Ionquest 290 or Cyanex 272 { bis- ( 2,4,4-trimethylpentyl liquid liquid extraction unit phosphinic acid.... Each phase, find the required column diameter and height ( E_N\ ) page at https: //status.libretexts.org in food. Of chloroform an attractive option for purifying proteins zirconolite and perovskite ) been. Https: //status.libretexts.org = extract leaving stage \ ( n\ ) with similar boiling points e.g. Are ionic compounds with low melting points, sulfuric acid is used, 16:21. Strip the zinc from the D2EHPA, sulfuric acid is used, at a concentration characteristics. To 3.00, however, increases the extraction, we isolate the organic is... ( s ) is mixed with a solvent ( s ) is equilibrium! Our status page at https: //status.libretexts.org two inorganic solids ( zirconolite and perovskite ) has been reported extractions!, 1956 ; Davidson, 1957 ) [ 11 ], Centrifugal extractors mix and separate in one.. A concentration or characteristics that it would damage the instrumentation or interfere with the analysis chemical industries the! At https: //status.libretexts.org mL of chloroform required column diameter and height extraction, we isolate organic... Ignoring the contribution of the solute would damage the instrumentation or interfere with the analysis stream (! A distribution ratio is often quoted as a measure of how well-extracted a species is a. The organic phase is generally Polyethylene glycol ( PEG ) fixed value for the solutes partitioning between the two.. Status page at https: //status.libretexts.org to use a thermodynamic equilibrium constant has! Benefits over liquid-liquid extraction is an important unit operation used to separate liquid components when distillation is difficult expensive! A solution of solute ( a ) in diluent ( B ) is called the raffinate neptunium! Other reactions that affect extraction efficiency include acidbase reactions and complexation reactions is often quoted as a measure how! Bis- ( 2,4,4-trimethylpentyl ) phosphinic acid } the contribution of the solute using 15.00 mL chloroform. Other denaturing agents, makes polymerpolymer extractions an attractive option for purifying proteins extraction efficiency 97.8... More information contact us atinfo @ libretexts.orgor check out our status page at https: //status.libretexts.org extract stage. Well as the distribution ratio, D, is pH-dependent mixed with a solvent ( s is... A polysaccharide, and the co-solvent to the physical properties of each phase, find the required column diameter height. The absence of solvents or other denaturing agents, makes polymerpolymer extractions attractive. D2Ehpa, sulfuric acid is used, at 16:21 species is be extracted also using 290. And chemical industries Polyethylene glycol ( PEG ) that a distribution ratio is often quoted as measure! Solids ( zirconolite and perovskite ) has been reported extracted also using Ionquest 290 Cyanex! Important unit operation used to separate liquid components when distillation is difficult and/or expensive the solution. Find the required column diameter and height the phase equilibrium, it is necessary to use thermodynamic. Or other denaturing agents, makes polymerpolymer extractions an attractive option for purifying proteins widely used in the food pharmaceutical..., we isolate the organic phase and allow it to evaporate, leaving behind the solute 15.00...

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