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Harie S. Jaya* et al. International Journal Of Pharmacy & Technology

IJPT| June-2016 | Vol. 8 | Issue No.2 | 14409-14421 4409

ISSN: 0975-766X

CODEN: IJPTFI

Available Online through Research Article

www.ijptonline.com CAVITATIONS ENERGY FOR HYDROLYSIS

Harie S. Jaya*a,b,c

, I.N.G. Wardana a,d

, Nurkholis Hamidia,e

and Denny Widhiyanuriawana,f

aDepartment of Mechanical Engineering, Brawijaya University, Jl. MT. Haryono167, Malang 65145, Indonesia.

bDepartment of Mechanical Engineering Education, Palangka Raya University, Jl. Yos Sudarso,

Palangka Raya 73112, Indonesia.

Email: [email protected]

Received on 08-06-2016 Accepted on 29-06-2016

Abstract

This paper is a preliminary study using cavitation energyto break thetriglycerides of palm oil into glycerol and fatty

acids.The cavities were generated by injecting water using fuel injection pumpvia a nozzle into palm oil in the helle

shaw cell in volumes of 3ml at pressures varying between 2 and 16 MPa. Glycerol amounts were measured

employing a colorimetric and acrolein test method. The result shows that the amount of glycerol formed was greatly

influenced by 3 factors, namely, bubble diameters, jet speed and size at 0.002 seconds shortly before the jet reach its

maximum speed. The smaller the bubble diameters and the greater the jet flow speed and size at 0.002 seconds, the

greater the amount of glycerol produced.

Keywords: Hydrodynamic, Cavitation, Hydrolysis, Crude palm oil.

Introduction

Much research and effort has already been done for observing and visualizing cavitations jets in order toelucidate

their role on hydrolysis reaction of vegetable oil so that the use of catalyst can be reduced. Studied the biodiesel trans

esterification process in soybean oil using hydrodynamic and acoustic (ultrasound) cavitations at a frequency of 19.7

kHz, where the oil were mixed with methanol in a liquid with sodium hydroxide (NaOH) as the catalyst. This study

reported that the use of hydrodynamic cavitations was the most efficient method and required minimum energy

compared to ultrasonic and conventional stirring methods(Jianbing et al.,2006).

Investigated the use of cavitational reactors for the synthesis of biodiesel and reported that cavitations could be very

successfully applied to the transesterification reactions with more than 90% production. Hence, the technique appears

to be much more effective than the conventional approach, which is also evident from the comparison of different

techniques based on the quantitative criteria of energy efficiency. Hydrodynamic cavitations are about 40 times more


IJPT| June-2016 | Vol. 8 | Issue No.2 | 14409-14421 Page 14410

efficient than acousticcavitations and 160-400 times more efficient than conventional agitation/ heating/ refluxing

methods(Gogate et al.,2005). Kumarhave shown that reaction rates when using hydrodynamic cavitations increases

by three times that of acousticcavitations at equivalent power dissipation rates (Kumar et al.,2000).

In heterogeneous liquid reactions, bubble can collapseat the interface between the two liquids resulting in mixing and

disruption of the solution which scatters one phase inside the other (D.Rooney et al.,2001 and S.Al-Zuhair et

al.,2002). Recently, researcher have shown that the ultrasonic process can produce a very fine and stable emulsion

with low energy input by increasing the surface area between two immiscible liquids (A.Patist et al.,2008). Normally,

enhanced reaction rates in cavitations systems are associated with free radicals, locally high temperatures and

pressure, enhanced mass transfer rates, or enhanced interfacial areas (S.Arrojo et al.,2007).

Pandit compared acoustic and hydrodynamic cavitations systems for the enhancement of oil hydrolysis. For the

hydrodynamic system, they used a 200 liters of oil-water mixture (with 1-10% oil) which was passed through a

throttled cavitating valve without any enzymes at 3 – 4 bars for about 40 hours. Hydrolysis could occur using the

hydrodynamic cavitations of ultra sound at (20 kHz for 10 h) at room temperature. They concluded that cavitations

provided localized high temperatures and pressures that enabled the reaction to take place. This work has been cited

in over 25 papers since but no reports of hydrolysis with hydrodynamic cavitations have been found. However,

ultrasonic cavitations havebeen used to enhance hydrolysis ( A.B.Pandit et al.,1993)

Talukder found an optimal power for ultrasonic enhancements of hydrolysis of olive oil by Chromo bacterium

viscosum lipasein a two-phase water/ isooctane system. They stated that this was associated with increased interfacial

area, but they also noted a more rapid loss of lipase activity with sonication (MMR.Talukder et al.,2006).Leeused

ultrasound to enhance lipase activity in ionic liquids and concluded that it increased the mass transfer rates without

causing loss of enzyme stability (S.H Lee et al.,2008). Yachmenev concluded that it enhanced enzyme transport and

opened up the surface of the solid substrate. But to date no research has been found that combined cavitations with

enzyme hydrolysis. In another enhanced hydrolysis process (V.Yachmenev et al.,2009). Weatherley and Rooney

found that an electrostatic system used with enzymes could be as efficient as steam splitting performed at 2400C and

33bar (L.R Wetherley et al.,2008) Giorno used microfiltration membranes to create emulsions for the distribution of

the Candida rugosa enzyme at oil/ water interfaces (L.Giorno et al.,2008).

Beuve studied the effectiveness of cavitations produced by using a venturi for enhancing the enzymatic hydrolysis of

canola oil using lipase from candida rugosa. Cavitations led to the production of fine oil-in-water and water-in-oil



emulsions with the enzyme in the water phase. Venture inlet pressures of up to 8 bars, yields fatty acids only about

60% of the maximum possible yield with reaction rates equal to, or better than those obtained in a cavitating system.

It was concluded that cavitations inhibited the reaction in some way and was not effective for intensifying hydrolysis

(Romain Sainte Beuve et al.,2010). Therefore, the aim of this study was to determine the effect of hydrodynamic

cavitations injected from a nozzle for enhancing the hydrolysis of palm oil without any enzymes at room

temperatures. Cavities were generated by injecting water via a nozzle attached to an injection pump at variable

pressures from 2 to 16 Mpa into palm oil bath.

Materials and Methods

Crude palm oil used in this study is a mixture of about 92 to95% oil, upto 5% free fatty acids (FFA) and about 0.5%

water, water soluble and solids. Generallythe oil is made up of triglyceride (94-97%), diglyceride (2-3.5%) and

monoglyceride (0.3-0.5%). The crude palm oil used in this study has composition as shown in Table 1.

Table-1. Fatty acids composition of crude palm oil (CPO).

Type of Fatty acids Fatty acids Components %

Saturated Palmitic C16 44,3

Stearic C18 4,6

Myristic C14 1,0

Monounsaturated Oleic C18 38,7

Polyunsaturated Linoleic C18 10,5

Others 0,9

This study was intended to analyze the effect of cavitations at various pressures on the hydrolysis reaction that breaks

the oil into fatty acids and glycerol. The experimental set up is shown schematically in Figure 1.



Figure-1. Schematic of Experimental Set Up.

From the tank water was vertically injected through the nozzleusing fuel injection pump into the open top helle shaw

cell containing the palm oil with volumes of 3 ml. As water passes through a nozzle of 1mm diameter, cavities was

formed at high jet speed due to the pressure drop called hydrodynamic jet cavitations, as shown in Figure 2. The

cavitations that occurred in the helle shaw cell were recorded using a Casio ZR-200 high speed camera then

processed with a video to jpg converter software. The bubble diameter was recorded by using a Dino-Lite microscope

with a magnification of 200 times and measured with ImageJ software. The experiments were conducted at ambient

pressure and room temperature.

The injecting water pressure was varied as 2, 4, 6, 8, 10, 12, 14 and 16 MPa. The glycerol produced at each pressure

was determined by acrolein and colorimetric tests. The acrolein test was employed to identify the content of glycerol

in the samples, with the addition of KHSO4,while the colorimetric assay was done by the addition of a specific

reagent and heating to form an emerald green color which indicates the sample containing glycerol.

Figure-2. Water Jet Flow Configuration in Palm oil.

Acrolein test was done by inserting 1mL of the sample solution (palm oil, glycerol, hydrolysis results in 2, 4, 6, 8, 10,

12, 14 and 16 MPa) into each test tube. A little KHSO4 was added to each tube and heated for boiling. The presence

of glycerol was marked by a rancid odor in the sample solution. In the colorimetric assay, 1 ml of sample solution

(palm oil, glycerol, hydrolysis results in 2, 4, 6, 8, 10, 12, 14 and 16 MPa) was entered into each tube. 1 ml NaOCl



was added to each tube. After 3 minutes, another 3 to 4 drops of HCl were inserted and then boiled to remove the

excess acid. After that, 0.2 mL of α–naphthol was added followed by addition of 2ml H2SO4 into each tube. The

presence of glycerol content was characterized by the solution color changing to emerald green.

Results

Glycerol content test

Colorimetrytest on sample from palm oil that has been injected by water jet at various pressure gives results having

two phases in different colors as shown in Figure 3. The change to emerald green indicates that there was a glycerol

in the samples as shown in Table 2.

Table-2. Colorimetri Test Data.

Sample Color Formed

Glycerol Emerald Green

Palm

Oil

2 phase = yellowish below +

brown above

2 Mpa 2 phase = emerald green below +

brown above


brown above


brown above


brown above


brown above


brown above


brown above


brown above

Remark:

Emerald green = contain glycerol

Yellowish = no glycerol



Figure-3. Colorimetri Test.

Table-3. Acrolein Test Data.

Sample 0,5 gram KHSO4 Smelly

Glycerol transparent – white

sediment

+++++

palm oil Brown ++

2 Mpa yellow – white

sediment

++++


sediment

++++


sediment

++++


sediment

++++


sediment

++++


sediment

++++


sediment

++++


sediment

++++

Remark:

+++++ = very smelly

++++ = smelling

+++ = pretty smelly

++ = rather smelly

+ = less smelly

- = odorless



As shown in Table 3 (the acrolein test), all samples were given the same treatment that is the addition of KHSO4, and

then reheated. KHSO4 was added to the sample to serve as a catalyst in the hydrolysis of lipids into fatty acid and

glycerol. Warming accelerates the formation of acrolein or otherwise assisted in the binding of water by akrilaldehide

KHSO4.

Akrilaldehide formation is marked by a special ranacid odor. To oxidize rancidity, double bonds in unsaturated fatty

acid components of the triglyceride were cut, forming lower molecular weighted aldehide with an offensive odor.

After that, aldehide oxidized into a fatty acid with a lower molecular weight which smells delicious. The acrolein test

was performed showing positive results for each, indicating that all the samples contained glycerol.

Glycerol production

The results of the hydrolysis process were poured into the measuring cup to measure the glycerol production as

shown in Figure 4. Yellow liquid in a measuring cup is crude palm oil (CPO) while glycerols which is transparent

white color are at the bottom of the palm oil due to density of glycerol (1,261 kg/m3) is greater than the palm oil

density (0.913 kg/m3).

Figure-4. Hydrolysis Result at 2,4,6,8,10,12,14 and 16 MPa.

Figure 5 shows glycerol production at each water injection pressure estimated fromthe measuring cup. Tetragonal

plot indicates the amount of glycerol producedat one injection, while square plot shows the amount of glycerol

producedat 20 times injection. It can been seen that at a pressure of 10 MPa (100 bar), the glycerol production is the

highest.

Figure-5. Amount of glycerol produced by hydrolysis reaction.



Discussions

Effect of Energy Cavitation

The kinetic energy generated from water injection using fuel injection pump into helle shaw, which amounted to 1/2

mv2 will result a pressure drop that occurs in the nozzle, due to changes in cross-section of the nozzle. If the pressure

drop become below than the saturated vapor pressure of water ( is equal to 4247 Pa at a temperature of 300C),the

liquid water turns into vapor phase at a constant temperature.

This vapor phase forms very small bubbles called cavitation. The pressure drop simulated using ansys fluent is shown

in figure 6. It can be seen that the static pressure drop to below 0 Mpa, indicating that the liquid water is changed

completely into cavitations at jet region.

Fig-6. Distribution of static pressure at 2 MPa (red line) and16 MPa (black line) along the axis direction.

Figure-7. Cavitation Energy and hydrolysis.

Energy of cavitations in this study, is used to ionize the 3H2O into 3H and 3OH that break the ester bond between C

and O atoms, contained in crude palm oil triglyceride to form glycerol and three fatty acids, as illustrated in figure

7.The carbon and oxygen bond in triglyceride is a bond of order one with an average length of 143 pm is 358 kJ /

mol. The higher the energy level the stronger the bond.Consequently, it takes more energy to terminate the bond.In

fact, glycerol was formed after the end of the reaction.This prove that at very large pressure drop the cavitations

generate energy greater than the energy bond between carbon and oxygen.



Effect of initial jet velocity on the formation of glycerol.

Figure-8. Jet Flow at various nozzle pressure.

Figure 8 shows the image of jet height evolution from the nozzle every 0.002 seconds atvarious pressures.It can be

seen that at pressureof 10 MPa, the jet height at 0,002 secondis the highest indicating the highest jet speed.Pressure of

2,4,6,8,10,12,14 and 16 MPa are the pressure at injection pump. While the output pressure of the nozzle with inlet

and outlet diameter of 6 mm and 0.8 mm respectivelywas estimated by using Bernoulli equation with the density of

water of 997 kg/m3 andvelocity coefesien (Cv) of 0,98. The pressure of palm oil which is at rest at the nozzle exitis is

1 atm.Water jet velocity at the nozzle exit was etimated as .The results are presented in table 4. As

tabulated in table 4, all estimated pressures at the nozzle exit are lower than 0 atm. This indicates that water injected

by the nozzle changes completely into steam to form cavities. The cavities provide sufficient energy for hydrolysis

reaction of the oil to produce glycerol and fatty acids.

Figure 9 shows the jet velocity from 0 s to 0.1 s. The velocity was estimated from the rate of change of jet height at

Figure 8 using ImageJ processor. As shown in figure9, the speed of jet stream at 10 MPa at 0,002s is 2785 mm / sec

which is the highest. This indicates that the rate of reaction could be the highest since the particles collide with

enough energy to start a reaction. It means that jet at 10 Mpa results in highest rate of hydrolysis reaction.



Table-4. Pressure and jet velocity.

Nozzle Inlet

Pressure (MPa)

V2 m/s Nozzle Exit

Pressure (Pa)

2 62,074 -1709847

4 87,786 -3419703

6 107,515 -5129511

8 124,148 -6839389

10 138,801 -8549152

12 152,049 -10258999

14 164,232 -11968877

16 175,571 -13678656

Figure-9. Jet speed against time.

Effect of innitial jet area on the reaction rate formation of glycerol

The Table 5 shows the jet area formed at 0.002 seconds. The reaction rate denote the number of chemical reactions

that occur per unit time One of the factors that affect the rate of reaction is the contact area.The largest jet area at 10

MPa means the largest number of cavitations causes the highest rate of hydrolysis reaction shown by the largest

amount of glycerol produced (see Figure 5).

Table-5. Jet Area and water volume.

Pressu

re

Jet area (mm2) Water volume

at

(MPa) 0,002

sec

0,004

sec

one injection

(ml)

2 3,10 31,71 7,5

4 3,15 45,04 9,0

6 25,94 70,06 9,0

8 25,36 47,04 10,5



10 55,08 71,07 12,0

12 24,86 114,2 13,5

14 48,81 56,40 15,0

16 47,28 68,70 18,0

Effect of the bubble diameter on the formation of glycerol

Figure-10. Bubble Formed at 2,10 and 16 MPa ( magnification 200 time)

Figure 10 shows the bubble diameters within measurement range formed at 2, 10 and 12 MPa. The image were taken

using a dino-lite microscope at a magnification of 200x less than 1 second after the water was injected into helle shaw

cell containing the palm oil at the same place. In general, the higher the pressure produce the smaller diameter of the

bubble as shown in Figure 11. However, in this study the average bubble diameters at 10 MPa is smaller than 2, 4,

6,8,12,14 and 16 MPa.

Figure 11. Bubble average diameter and skewness.

Figure 11 shows the average bubble diameter and skewness factor at each pressure of the nozzle. The average

diameter of the smallest bubbleis 0.225 mm at 16 MPa.A unique phenomenon occurs at 10 Mpa where the bubble

diameter is drop. This phenomenon gives larger amount of glycerol. Skewness is a measure of symetry of bubble

diameter. Negative values for the skewness indicate data that are skewed left and postive values for the skewness

indicate data that are skewed right. By skewed left, means that the left tail is long relative to the right tail. Similiarly,

skewed right means that the right tail is long relative to the left tail. The positive skewness factor at all nozzle

pressure show that the cavitations diameter produced by the jet issmall and some larger diameter are produced



intermittently. The skewness data at 10 Mpa also shows that the bubble diameter drop. Therefore, figures 10 and 11

confirm that bubble diameters at 10 Mpa are the smallest. The smaller the diameter of the cavity produced by the

nozzle, the greater the cavitation surface energy, so that the reaction between water cavity with palm oil become

increasingly effective and therefore glycerol production is increased.

Conclusions

Hydrolysis reaction can be carried out without the use of catalysts or enzymes at atmospheric pressure and room

temperature by using hydrodynamic jet cavitation. Hydrodynamic jet cavitation produced by compressing water

through a nozzle and vertically injected into helle shaw cell containing palm oil. In this study, the highest glycerol

production isat 10 MPa (100 bar). This is so because the average bubble diameters formed at 10 MPa were smaller

than those at 2, 4, 6, 8 and 12 MPa. In addition, the average diameter of the bubbles is influenced by the speed of the

jet flow from the nozzleat at0.002 seconds at 10 MPa which is faster than the others. The jet speed at the beginning

produces maximum momentum energy between water and oil cavities thus producing large amounts of glycerol.

This study found that the greatest amount of glycerol production at pressure of 10 MPa is due to 3 factors, namely,

the smallest cavity diameters, the highest jet speed and jet areas at 0.002 seconds.

Acknowledgements

The author is deeply grateful to Prof. Ir. ING Wardana PhD (Supervisor) for encouraging and supporting this

research program, and to the co supervisor(Dr. Eng Nurkholis Hamidi and Dr.Eng.DennyW.) for the assistance in

fluid dynamic simulation.

References

1. Ji, J., Jianli Wang, Yongchao Li, Yunliang Yu and Zhichao Xu, 2006 Preparation of Biodiesel with the help of

Ultrasonic and Hydrodynamic Cavitation,Proceedings of Ultrasonics International (UI’05) and World Congress

on Ultrasonics (WCU) Volume44, Supplement, 22 Desember 2006, Pages e411-e414.

2. Gogate, P.R., and AB. Pandit.,2005, A Review and Asessment of Hydrodynamic Cavitation as a Technology for

The Future,Elsevier Journal Ultrasonics Sonochemistry 12: 21– 27.

3. Kumar, P.S., M. Siva Kumar and A.B Pandit.2000, Experimental quantification of chemical effect of

hydrodynamic cavitation, Elsevier JournalChemical Engineering Science 55:1633-1639.

4. Rooney,D. and L.R.Weatherley. 2001. The Effect of reaction conditions upon lipase catalysed hydrolysis of high

oleate sunflower oil in a stirred liquid–liquid reactor, Process Biochemistry. 36(10): 947–953.



5. Al-Zuhair S., M.Hasan and K.B.Ramachandran. 2003. Kinetics Hydrolysis of Palm Oil Using

lipase.ProcessBiochemistry. 38(8):1155–1163.

6. Patist,A. andD. Bates. 2008. Ultrasonic innovations in the food industry: From the laboratory to commercial

production, Innovative Food Science Emerging Technologies, Food Innovation: Emerging Science, Technologies

and Application (FIESTA) Conference, 9(2),147–154.

7. Arrojo S, Nerín Cand Benito Y. 2007. Application of salicylic acid dosimetry to evaluate hydrodynamic

cavitation as an advanced oxidation process, Ultrason Sonochem. 14(3): 343–9.

8. Pandit,A.B. and J.B.Joshi, 1993. Hydrolysis of fatty oils: effect of cavitation, Chemical Engineering Science

48(19) : 3440–3442.

9. Talukder, M.M.R., M.M.Zaman,Y.Hayashi,J.C.Wu and T. Kawanishi. 2006. Ultrasonication enhanced

hydrolytic activity of lipase inwater/isooctanetwo-phase systems, Biocatalysis and Biotransformation 24 (3):

189–194.

10. Lee, S.H., H.M Nguyen, Y.M Koo and S.H. Ha. 2008. Ultrasound-enhanced lipase activity in the synthesis of

sugar ester using ionic liquids, Process Biochemistry 43:1009–1012.

11. Yachmenev,V., B.D. Condon, K.T. Klasson and A.H. Lambert. 2009. Acceleration of the enzymatic hydrolysis

of corn stover and sugar cane bagasse celluloses by low intensity uniform ultrasound, Journalof Biobased

Materials and Bioenergy. 3(1): 25–31.

12. Weatherley, L.R. and D. Rooney. 2008. Enzymatic catalysis and electrostatic process intensification for

processing of natural oils, Chemical EngineeringJournal. 135: 25–32.

13. Giorno,L., E. Piacentini, R. Mazzei and E. Drioli. 2008 Membrane emulsification as a novel method to distribute

phase-transfer biocatalysts at the oil/water interface in bioorganic reactions, Journal of Membrane Science 317:

19–25.

14. Beuve, R.S.and Ken Morison. 2010. Enzymatic hydrolysis of canola oil with hydrodynamic cavitation,

Chemical Engineeringandprocessing49(10):1101-1106.

Corresponding Author:

Harie S. Jaya*,

Email: [email protected]

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