Present Status and Future Development
                of the Forest Chemical Sector
                        By Zhao Shoupu
(Senior Engineer of the Forest Chemical Industry  Institute
of the Chinese Academy of Forest Sciences)
The forest chemical sector  is  an  industry  using  forest
products as raw  materials  to  produce  various  chemical
products by chemical processing methods. After development
for several dozens of years, the forest chemical sector in
China has become an industrial system with more  than  600
producers and over 100 product  varieties.   It  holds  an
important position in the national economy.  Major  forest
chemical products include rosin, turpentine, chemical uses
of plant tannin and activated carbon.
1. Rosin and turpentine
China produces 500 000 tons of rosin a year. It is produced
by chemical synthesis mainly using pine gum as raw material.
The domestic output accounts for more than  one- third  of
the world total. The export amount is over 300  000  tons,
accounting for more than a half of the world  rosin  trade
amount. Rosin in China holds a swaying role in  the  world
market and  is  a  major  export  product  in  the  forest
chemical sector.
The reprocessing of rosin in producers started from the  70
in China. The reprocessing was done by users in the  years
before the 70. There is already commercial  production  of
  reprocessed  products  such   as   hydrogenated   rosin,
disproportionated rosin, maleic rosin, polymerized  rosin,
various rosin esters  and  abietylamine.   The  output  of
turpentine in China is 50  000  -   60  000  tons.   Major
reprocessed products  include  camphor,   bornyl  alcohol,
terpene resin, terpineol, pine oil,a -pinene,   b- pinene,
linalool and isolongifolilene, as well as isolongifolinone
produced from heavy turpentine.
A great deal of research has been done in the recent years
in expanding pine gum recovery capacity and developing new
reprocessed products. There will be a bright prospect  for
research and  development  of  rosin  polyurethane  foamed
plastics, colorless rosin and esters, rosin  and  modified
rosin emulsions, synthetic peruviol, geraniol, rosin paper
-making sizing material and pinoline  resin,   as  well  as
insulation paints, surfactancts and epoxy resins  produced
from rosin. Some of  the  products  have  already  started
production.
China has  a  history  of  more  than  40  years  in  rosin
  production.   To  make  a  stable  development  of  rosin
production, we  have  to  establish  raw  material  bases,
enhance scientific research, cultivate high-yield pine gum
trees and  develop  specialized  and  efficient  pine  gum
recovery. Satisfactory results have already been  achieved
in some areas, and further progress will be made in future
. It is expected that by enhancing scientific research  and
basic foundation work the rosin sector in China will  hold
a leading position in the world in output, technology  and
product variety.
2. Chemical uses of plant tannin
The chemical uses of plant tannin in China  mainly  include
the production of tannin extract and the use of  gall  nut
tannin. The production of tannin extract mainly  uses  the
bark of dahuian larch, red bayberry and emblic and valonia
as raw materials. The highest output reached 50 000  tons.
The demand of dark color tannin extract has reduced in the
recent years, and the output today is 10 000 - 15 000 tons
. More than 10 producers make the production of tannic acid
, gallic acid and their derivatives  from  gall  nut.   The
output is around 3  000  tons.   Besides  the  traditional
process of acidic hydrolysis, the commercial production of
gallic acid using the process of enzymatic hydrolysis  and
alkali hydrolysis has also started. The production of drug
raw  materials  such  as  trimethoxyl  benzoyl  hydrazine,
trimethoxyl benzaldehydride and trimethoprim produced from
tannic acid and gallic acid has made great development and
yielded remarkable economic benefits.  The  production  of
pyrogallic acid has developed  fast  in  China,   and  the
product is mainly exported to Japan.
In the leather tanning sector, HS retanning agent  produced
by complexation  of  valonia  extract  with  aluminum  and
  chrome  ions  has  started  production  and  utilization.
  Another  retanning  agent   produced   by   grafting   co
-polymerization and modification treatment of dahuian larch
tannin and acrylic monomer has  excellent  permeating  and
filling properties.
Tannin extract made from the bark of dahuian larch and  red
bayberry is successfully used to produce tannin adhesives.
They use liquid formaldehyde as curing  agent  and  has  a
long-lasting activity and an adjustable viscosity.
Owing to its low price, tannin drilling  thinner  has  been
acclaimed by oil producers. Potassium tannate contained in
the agent has  good  collapse  resistance.   The  grafting
copolymer of tannin and lignin has the advantage  of  high
activity in tannin and also  the  advantage  of  salt  and
temperature resistance in lignin. When used as thinner, it
can perform  good  comprehensive  functions  of  salt  and
temperature resistance,  stickiness  reduction  and  water
loss prevention.
Tannin high-temperature blocking agent used to increase the
oil recovery rat