Wood, Pulp and Paper Product Chemistry

Econotech has the expertise, equipment and established procedures to explore the composition of wood and non-wood fiber sources, and resulting pulp products.

Pulp Fiber

We analyse the chemical and physico-chemical properties of pulp fiber in detail.  For example:

• Cellulose and Hemicellulose content may be investigated via classic methods such as caustic resistance/solubility or pentosan oxidation, or alternatively by liquid chromatography analysis of hexose and pentose carbohydrate species.
• The viscosity of a standardized solution of dissolved pulp gives a useful indication of the degree of cellulose polymerization and the level of pulp degradation. We have methods to suit all types of pulp and the expertise to cross-reference and compare results obtained with different methods.
• Determination of carboxyl and aldehyde functional groups, responsible for both aging characteristics and inter-fiber bonding and strength properties in pulp products, also has value for specific applications.
• Residual lignin content of pulp may be determined by several possible test methods, depending on the application and level of detail required. Kappa and Permanganate Number are useful references, while Klason and complementary acid-based analyses may be used to quantify acid soluble and insoluble fractions.

Many other tests are available to assess:

• • General pulp chemical properties
  • Carry-over of process and non-process elements into pulp from pulping and bleaching
  • Incorporation of beneficial chemical additives into paper product

Fiber Supply

If you’re going through a shift in fiber supply and experiencing unaccounted variability, or investigating the feasibility of an alternative fiber source, then a better understanding of feedstock properties is a good foundation to build on.

A chemical analysis of wood chips can determine the cellulose, hemicellulose and lignin content which affects both the conditions required in your digester and the final physical and optical properties of your pulp or paper.

Feedstock and attached dirt are a source of non-process elements, notably potassium, chloride, silicon, calcium, and magnesium, as well as various other anions and metal cations. These NPEs can generate scales and deposits, act as deadload, or be otherwise problematic in pulping process and products. When there are issues, understanding the contributions from furnish can be a useful data point.

Commonly Tested Properties – Fiber Chemistry

A
Acid insoluble ash (free carbon)
Acidity or alkalinity, pulp
Alpha, Beta, Gamma cellulose
Anthraquinone
Ash @ 525°C, @ 725°C, @ 1000°C
Ash fusion temperature – oxidizing or reducing atmosphere

C
Carboxyl and aldehyde functional group content
Carbohydrates (wood sugars: arabinan, galactan, glucan, mannan, xylan)
Caustic solubility, (1%, 10%, 18%, 21.5%)
Chemical Oxygen Demand, COD
Chloride
Chloride, water soluble
Chloriting (delignification)
Chromium, hexavalent
Conductivity
Consistency, pulp suspensions
Copper number

E
Extractives (DCM, acetone, hexane, ether)

F
FDA Extractives (alcohol, chloroform, heptane)
Formaldehyde

H
Hemicellulose (S18)
Hexaneuronic acid

K
Kappa number
Klason lignin

M
Metals / Cations
Methanol
Moisture (oven dry method)

O
Organo-Silicone

P
Pentosans (5-carbon sugar polysaccharides)
Permanganate number (K number)
pH (hot or cold)
Pitch, detrimental in pulp
Potential tall oil in wood
Potential turpentine in wood

S
Silica
Sodium (total, washable and bound sodium)
Soluble Lignin
Surface pH
Starch
Sulfate, water soluble
Sulfite, water soluble
Sulfur, Parr oxygen bomb
Sulfur, reducible (TRS)
Sulfur, total and bound

T
Talc / Magnesium Silicate

V
Viscosity (0.5% CED, 1% ball fall, LOIV, Intrinsic)