5-methylresorcinol with a reported purity of > 99% was provided by AS VKG, Estonia and 2,6-dihydroxy-4-methylbenzoic acid, with a purity of > 99%, was provided by Carboshale OU, Estonia.
A method for preparing metal-doped carbon aerogels from oil shale processing by-products 5-methylresorcinol and 2,6-dihydroxy-4-methylbezoic acid was developed.
Analogically to the complex with
5-methylresorcinol [7], the complex formed is assumed to dissociate as a weak acid as follows:
We have experience with the co-condensation of some methylolxylenols and dimethylolcresols with resorcinol and
5-methylresorcinol (8).
Musso and co-workers carried out basic and experimental studies on phenol oxidation reactions, including autoxidation of
5-methylresorcinol and 2,5-dimethylresorcinol in ammonia and potassium hydroxide [16,17].
Phenol, resorcinol and
5-methylresorcinol were used as both single and mixed substrates in the experiments.
5-Methylresorcinol with a reported purity of 99.58% was obtained from Carboshale AS and Honeyol[R] containing 56%
5-methylresorcinol was obtained from VKG AS, these materials were was used as received.
As
5-methylresorcinol has in addition to two hydroxyl groups a methyl group in the 5th position, a relatively fast gelling in comparison with the resorcinol-formaldehyde gel formation could be expected.
5-Methylresorcinol of purity [greater than or equal to] 96% was obtained from Carboshale, Estonia; Honeyol[TM] which is a product of Viru Keemia Grupp, Estonia, was obtained from Department of Oil Shale Technology of Tallinn University of Technology; the catalysts were [Na.sub.2]C[O.sub.3] (purity 99.8%) from Sigma Aldrich Laborchemikalien GmbH, Germany, and KOH from Chemapol Lachema Brno, Czech Republic; formaldehyde was in the form of 35% solution in water, obtained by dissolving paraform in distilled water, when paraform (purity 95%) was from Sigma Aldrich Laborchemikalien GmbH, Germany.
Due to the high content of different harmful compounds [2], the leachates of SC dumps in the amount of about 6,000-7,000 [m.sup.3] per day, containing 300-500 mg/L phenols, including relatively stable
5-methylresorcinol and p-cresol, sulphide ions, polyaromatic hydrocarbons and other toxic compounds [3], are one of the greatest sources of contamination of surroundings and water in the region close to the Finnish Gulf and cause a high load on the wastewater purification system.
During the period of 1991-1998 intensive studies on chemical oxidation of different phenolic effluents (containing phenol, cresols, resorcinols,
5-methylresorcinol, etc.) were carried out at the Chemical Engineering Department of Tallinn Technical University [4-8].
Phenol, p-cresol, o-cresol, resorcinol,
5-methylresorcinol and 2,4-, 2,6-, 3,4- and 3,5-dimethylphenol were used as single substrates in the experiments.
