Kuliah 5
Disain Produk Basic Chemicals
TK 4095 Disain Produk Industri
Kelas C - Semester Ganjil 2016/2017
Program Sarjana Teknik Kimia Universitas Riau
Objective
After completing this section, student should:
Be able to construct an innovation map for a basic chemical.
Be able to identify critical inventions and innovations involving
materials technologies for basic chemical products.
Be aware of typical considerations in specifying the physical
properties and performance of potential chemical products.
Know how to set up a search for chemicals and chemical
mixtures that satisfy specifications for physical properties.
Understand the role of group-contribution methods, and
other molecular modeling techniques, in estimating
properties during molecular-structure design
Basic Chemicals Product Design
Basic chemicals are normally well-defined molecules
and mixtures of molecules characterized by
thermophysical and transport properties.
Not described by other properties, including
microstructure; particle-size distribution; and
functional (e.g., cleansing, adhesion, shape),
sensorial (e.g., feel, smell), rheological (nonNewtonian viscosity), and physical (e.g., stability)
properties.
Innovation Map
The concept of an innovation map is developed
showing the connections between the technological
components and customer satisfaction, that is, the
customer value proposition.
To create an innovation map, it is important to
examine the key technological inventions that have
accompanied chemical products that are closely
related to the product being designed.
INNOVATION MAP FOR ENVIRONMENTALLY
FRIENDLY REFRIGERANTS
To construct the innovation map for environmentally friendly
refrigerants , first identify the elements in its four levels, moving
from the bottom to the top of the map:
Materials Technology: compounds involving C, N, O, S, H
atoms, and halogens F and Cl; compounds having large Tvb,
low m, and low Tm; compounds involving C, H, and F;
compounds involving C, H, F, O, and S.
Technical Differentiation (Technical-Value Proposition):
intermediate volatilityboils at 40 to 0oC at low pressure;
leaks easily detected; doesnt react appreciably with O3
stable and inert.
INNOVATION MAP FOR ENVIRONMENTALLY
FRIENDLY REFRIGERANTS
Products: Freons (C, Cl, F, H), e.g., R-22CHClF2; HFC 134a
(CFH2CF3); CH3CHF2.
Customer-Value Proposition: low-cost refrigeration and air
conditioning; nontoxic; safenonflammable; no reactions
with O3 in stratosphere (CFCs banned); low smog potential
no trace materials in lower atmosphere.
INNOVATION MAP FOR ENVIRONMENTALLY
FRIENDLY REFRIGERANTS
SEARCHING FOR NEW MATERIALS
BASIC CHEMICAL PRODUCTS
New chemical products is motivated by a desire to
improve the capabilities and performance of existing
products.
New products are sought that are lighter, stronger,
biodegradable, safer to manufacture, less toxic, and
more environmentally friendly.
PROPERTY ESTIMATION METHODS
Theoretical approaches to molecular-structure
design require accurate estimates of physical and
transport properties.
These are derived commonly from the principles of
thermodynamics and transport phenomena, often
using molecular simulations.
Usually, bond- or group-contribution methods are
used to estimate the constants and parameters for
pure species, with the designer providing the
molecular structure of the chemical species
Types of Properties
Thermodynamic Properties
Transport Proprieties
Kinetic Properties
Vapor Pressure of Mixture
VOC Volatile organic content
Flash Calculation with Process Simulator
Hand Calc.
Equation of State
Activity Coefficient Equation
Aspen/ProMax
Pick Thermo Package
Several are available
Polar liquids vs non-polar
Aqueous vs non-aqueous
High P vs low P
Input Components
Set up Flash unit with feed streams
Set Feed Stream composition
Run Calc
Vapor
Liquid
Solid
Design Methods
Physical Properties
Group Contributions
Thermo package in Process Simulator
Process Simulation of Refrigeration cycle
Condenser
Vaporizer
Pump
Valve to flash liquid to vapor
Refrigerant Design
Large negative Joule-Thompson Coefficient
Large Enthalpy of Vaporization
High Liquid Heat Capacity
Low Pressure -Tboil below RT
Vapor Pressure > 1.4 Bar to assure no air leaks
High Pressure Compressor/Condensor
Vapor Pressure < 14 Bar to keep compression ratio less
than 10
Solubility Parameter Prediction
Solubility Parameter
Solubility of liquid in liquid
Solubility of solid in liquid
Solubility of polymer in liquid
Group Contributions
Three parameters
Dispersive
Polar
Hydrogen Bonding
Flory-Huggins solution theory
The result obtained by Flory[1] and Huggins[2]
is
The right-hand side is a function of the number of moles n1 and volume
fraction 1 of solvent (component 1 or a), the number of moles n2 and
volume fraction 2 of polymer (component 2 or b), with the introduction
of a parameter chi, , to take account of the energy of interdispersing
polymer and solvent molecules.
Molar volume of polymer segment
are Hildebrand solubility parameters, =((Hvap-RT)/Vmolar)
=(d 2 + p 2 + h2), linkage to Hansen Solubility parameters
Hansen Solubility Parameter
Hansen Solubility Parameters were developed by Charles Hansen as a way of predicting if
one material will dissolve in another and form a solution [1]. They are based on the idea that
like dissolves like where one molecule is defined as being 'like' another if it bonds to itself in
a similar way.
Specifically, each molecule is given three Hansen parameters, each generally measured in :
The energy from dispersion bonds between molecules
The energy from polar bonds between molecules
The energy from hydrogen bonds between molecules
These three parameters can be treated as co-ordinates for a point in three dimensions also
known as the Hansen space. The nearer two molecules are in this three dimensional space,
the more likely they are to dissolve into each other. To determine if the parameters of two
molecules (usually a solvent and a polymer) are within range a value called interaction radius
(R0) is given to the substance being dissolved. This value determines the radius of the sphere
in Hansen space and it's center is the three Hansen parameters. To calculate the distance (Ra)
between Hansen parameters in Hansen space the following formula is used:
Combining this with the interaction radius gives the relative energy difference (RED) of the
system:
RED < 1 the molecules are alike and will dissolve
RED = 1 the system will partially dissolve
RED > 1 the system will not dissolve
Group Contribution Methods
Group (bond) Contribution
Methods
ni=number of groups of type i
in polymer repeat unit or
molecule
N= number of group types
Ai=group contribution to
property p{n}
Mwi= Molecular weight of
group I, sometimes another
group contribution property
d=exponent for property
Ai ni
i 1
p{n} N
Mwi ni
i 1
Group Contribution Methods
Polymer Glass Transition Temp.
Polymer Molar Volume
Polymer Density
Polymer Water Absorption
P. 66 of your book
Liquid Surface Tension/Wetting
Group Contribution Method
Contact Angle Youngs Equation
cos = (SV- SL)/ LV
Wetting when => 0
Predicting Liquid surface tension
LV=[LMw-1 (NiPi)]4
Pi=Parachor Value of group
Surface tension in [dyne/cm]
Density [gm/cm^3]
Mw [gm/mole]
Liquid Mixtures surface tension based upon mole fraction, Xi
LV= LV_iXi
Parachor Values
CH2=CH O CH3
Groups
C
3
H to C
6
O to ether
1
Double Bond
1
Pi
4.8
17.1
20
23.2
LV=[LMw-1 (NiPi)]4
Tables from Ring, Fundamentals of Ceramic Powder
Processing, Academci Press 1999.
Select Surfactants for Dispersion
Lower Surface tension of a liquid
Detergency
Hydrophilic-lipophilic Balance-HLB
HLB = 7+ Hi Li
Stabilized Suspension
HLBsurfactant= HLBparticle
Tables from Ring, Fundamentals of Ceramic Powder Processing, Academic Press 1999.
Group Contributions - HLB
TiO2
Tables from Ring, Fundamentals of Ceramic Powder Processing, Academic Press 1999.
Drago E and C
Used to predict the Heat of mixing, HAB
Acid (A) Base (B) Interactions
Good for non-polar solvents
H AB E A E B C AC B
E = Electrostatic Contributions
C = Covalent Contributions
Acids
Bases
Can be predicted from Infrared or NMR peak shifts due to mixing
See Wettability By John C. Berg
Wetting - Good Method
Work of Adhesion between to materials,
WaAB= -(SV-SL) LV Energy to replace solid-vapor and liquidvapor interfaces with liquid-vapor interface.
Predicted by
Liquid
Wetting Fowkes (Drago) Method
Work of Adhesion
N = moles of interaction functional groups per unit
area
f = factor to convert enthalpy to work
Transport Properties
Molecular Dynamics Calculations
Intermolecular Forces
Lennard-Jones Potentials between Atoms
Location of Atoms in Molecule
Molecules Free to move
Monte Carlo Methods
Statistical Analysis
Molecular Structure Determined From Otimization
Drug Molecule Binding
DAB=<x>2/t
Gives Upper and Lower Bounds of Property
Drug/Enzyme Target Development
Bio Concentration
BioConcentration factor=BCF
log BCF = 0.76 log Kow-0.23
Kow =octanol/water partition factor
Kow =Xo_w/Xw_o=(o_wMwo)/( w_oMww)
Easily get this from a liquid-liquid Flash calc.
Toxicity
LC50=lethal concentration when 50% are dead
log LC50= -0.87 log Kow - 0.11
Kinetic Parameter Prediction
Flash Point
Tf =0.683 Tboil-119K
Explosive Potential depends upon the flash
point
Tboil from flash calc.
Many Desired Properties of a Product
1) Determine list of desired properties
2) Use desired properties to determine
Figure of Merit
Grouping of Important Qualities for a product and/or its
use.
Minimized Deviations from Ideal Property Values
Minimize (Ai-Adesired)2 for various properties, Ai, for
product formulations. [p. 49]
Often minimization is carried out with upper and lower
bounds on specific properties or in comparison with
competitors product
