Method

What is Method?

Method is used to select the thermodynamic model that Dynochem will use to calculate activity coefficients (non-ideality). The options are: Ideal, UNIFAC VLE, UNIFAC LLE, UNIFAC modified, NRTL and UNIQUAC. You can access these in the edit model section of the Dynochem ribbon.

Defining the thermodynamic method for solvents in the properties database

The thermodynamic method is defined in the components tab, as shown below. For solvents in our properties system, there is nothing more for you to do.

For solvents in our properties system, there is nothing more for you to do. These solvents are listed below with their CAS RN.

Changing the thermodynamic method

There are two ways to change the thermodynamic method:

1. You can type Method followed by the name of the new method (Ideal, UNIFAC VLE, UNIFAC LLE, UNIFAC modified, UNIQUAC or NRTL) on the next cell to the right.

2. You can change the thermodynamic method by going to Components in the Edit Model section of the Dynochem ribbon. Scroll down to Method and select the one you want to use. This new method will replace the old one.

Defining the thermodynamic method for components that are not in the properties database

If you define a thermodynamic method and one or more of the components in your Dynochem model are not in the properties database, you may wish to provide additional information in the components tab depending on the the model you have chosen.

1. UNIFAC VLE/UNIFAC LLE/UNIFAC modified

If you have selected any of the UNIFAC methods, you need to provide the UNIFAC groups for the components that are not in the database. These need to be listed to the right of the MW (molecular weight).

2. NRTL

If you have selected the NRTL method, you will need to provide User Defined BIPs, shown below:

More information on how to add User Defined BIPs is given in the User Defined BIPs help page.

3. UNIQUAC

If you have selected the UNIQUAC method, you will also have to provide the UNIQUAC R, UNIQUAC Q groups and the User defined BIPs

More information on how to add User defined BIPs is given in the User Defined BIPs help page

Solvent list in the properties system

You can find the solvents in the database by click on DC functions and selecting DC_SourceBIPs. Click on the next box called Solvent1 to get a dropdown menu of all the solvents available in the database.

List of UNIFAC groups

Below is a table of valid UNIFAC VLE groups

CH3	HCOO	CHCL	DMSO	CCLF2	C4H4S
CH2	CH3O	CCL	ACRY	HCCLF2	C4H3S
CH	CH2O	CH2CL2	CL-(C=C)	CCLF3	C4H2S
C	CHO	CHCL2	ACF	CCL2F2	NCO
CH2=CH	FCH2O	CCL2	DMF-1	CONH2	(CH2)2SU
CH=CH	THF	CHCL3	DMF-2	AMH2	CH2CHSU
CH2=C	CH3NH2	CCL3	HCON(..	CONHCH3	IMIDAZOL
CH=C	CH2NH2	CCL4	CF3	AMHCH3	BTI
C=C	CHNH2	ACCL	CF2	CONHCH2
ACH	CH3NH	CH3NO2	CF	AMHCH2
AC	CH2NH	CH2NO2	COO	CON(CH3)2
ACCH3	CHNH	CHNO2	SIH3	AM(CH3)2
ACCH2	CH3N	ACNO2	SIH2	CONCH3CH2
ACCH	CH2N	CS2	SIH	AMCH3CH2
OH	ACNH2	CH3SH	SI	CON(CH2)2
CH3OH	C5H5N	CH2SH	SIH2O	AM(CH2)2
H2O	C5H4N	FURFURAL	SIHO	C2H5O2
ACOH	C5H3N	(CH2OH)2	SIO	C2H4O2
CH3CO	CH3CN	DOH	NMP	CH3S
CH2CO	CH2CN	I	CCL3F	CH2S
CHO	COOH	BR	CCL2F	CHS
CH3COO	HCOOH	CH=-C	HCCL2F	MORFOLIN
CH2COO	CH2CL	C=-C	HCCLF	MORPH

Below is a table of valid UNIFAC LLE groups

CH3	OH	FCH2O	CH2CL2	DOH
CH2	P1	THF	CHCL2	DMSO
CH	P2	ACNH2	CCL2	(CH2)2SO
C	H2O	C5H5N	CHCL3	DMFA
CH2=CH	ACOH	C5H4N	CCL3	HCON(CH3)2
CH=CH	CH3CO	C5H3N	CCL4	DEOH
CH2=C	CH2CO	CH3CN	ACCL	(HOCH2CH2)2O
CH=C	CHO	CH2CN	CH3NO2	TCE
ACH	CH3COO	COOH	CH2NO2	CCl2=CHCl
AC	CH2COO	HCOOH	CHNO2	MFA
ACCH3	CH3O	CH2CL	ACNO2	HCONHCH3
ACCH2	CH2O	CHCL	FURFURAL	TMS
ACCH	CHO	CCL	(CH2OH)2	(CH2)4SO2

Below is a table of valid UNIFAC modified groups

CH3	CHO	COOH	I	CHCL3	(CH2)2CB
CH2	CH3COO	HCOOH	BR	NMP	CH2CH3CB
CH	CH2COO	CH2CL	CH=-C	NEP	(CH2)2SU
C	HCOO	CHCL	C=-C	NIPP	CH2SUCH
CH2=CH	CH3O	CCL	DMSO	NTBP	CH3S
CH=CH	CH2O	CH2CL2	ACRY	CONH2	CH2S
CH2=C	CHO	CHCL2	CL-(C=C)	CONHCH3	CHS
CH=C	CH3NH2	CCL2	ACF	CONHCH2	C3H2N2+
C=C	CH2NH2	CHCL3	DMF	AM(CH3)2	C3H3N2+
ACH	CHNH2	CCL3	DMF-2	AMCH3CH2	BTI-
AC	CNH2	CCL4	HCON(..	AM(CH2)2	C4H8N+
ACCH3	CH3NH	ACCL	CF3	HCONHCH3	BF4-
ACCH2	CH2NH	CH3NO2	CF2	HCONHCH2	C5H5N+
ACCH	CHNH	CH2NO2	CF	AC2H2S	C5H4N+
OH (p)	CH3N	CHNO2	COO	AC2HS	OTF-
OH (s)	CH2N	ACNO2	CY-CH2	AC2S	-S-S-
OH (t)	ACNH2	CS2	CY-CH	H2COCH	SO4
CH3OH	AC2H2N	CH3SH	CY-C	COCH	HSO4
H2O	AC2HN	CH2SH	THF	HCOCH	PF6
ACOH	AC2N	FURFURAL	CY-CH2O	H2COCH2
CH3CO	CH3CN	(CH2OH)2	TRIOXAN	H2COC
CH2CO	CH2CN	DOH	HCOOH	(CH3)2CB