This page covers my activities under the company Carina Chemical Laboratories Ltd. This company was formed in 1986 to provide the minor partner in a Joint venture with ICINZ with a research capability in a development to convert durene to pyromellitic dianhydride (a component for heat resistant plastics) and a development to make agar from unsorted seaweed as found on the beach. The collapse of these joint ventures together with the 1987 financial crash led to severe retrenchment, although the company continued. Now I am the sole staff member and because of my age, no new clients are being sought. Current activities are restricted to two projects:

(a) Seaweed uses: A patented product made from agarose has been used to make skin gels with unusually effective uses. The gel partially dries and contracts, leading to a film above much of the skin, and this leads to improved delivery of actives to the skin, and it creates a good humidity above the skin, thus maintaining good skin hydration, even when the air is very dry. A range of products have been developed and can be purchased at http://www.nemidon.com.

(b) Bioprocessing: Currently, chemical advice is offered to a project aimed at making charcoal, graphite, and other carbon products. See http://carbonscape.com.

Historical details

Durene (1,2,4,5-tetramethylbenzene) derived chemicals

The ZSM5 catalysts of the Motunui Synfuels plant produced a stream of "heavy gasoline" from which one could potentially obtain approximately 35,000 t/a of durene, a hydrocarbon otherwise having to be produced by chemical synthesis. In 1986, ICI Synchem Ltd, a joint venture company, won the rights from the New Zealand Government (which owned the hydrocarbon stream) to purchase durene to convert it to pyromellitic acid and to pyromellitic dianhydride, a raw material for a number of temperature resistant polymers, including polyimides. Carina developed routes for manufacturing a number of durene-based chemicals and investigated prospective uses for them, including a number of pentacene-5,7,12,14-tetrones (mainly photochemical properties), duroquinone , pyromellitic diimide, to be used as a ruminant methane inhibitor) or for polymer curing, 1,4-di(aminomethyl)-2,3,5,6-tetramethylbenzene, and a number of polymer intermediates. The pentacene tetrones make dyes analogous to the anthraquinone dyes as well as acid-base indicator dyes, but they can also be strong photodegradative agents. 1 kg of pyromellitic diimide was made and was used to inhibit methane formation in a number of sheep over a year. The objective here was to make food supplements last longer during droughts, and food uptake efficiency was strongly enhanced. Initial targets for the venture included low mobility plasticizers and polyimides. The original promotion included a TV appearance with a demonstration of the fire-resistance of "home-made" polyimide foam, and while the pictures of that are unavailable, the effectiveness is shown on http://www.youtube.com/watch?v=i4kCAP4sQU8.

Agar and Agarose production

In 1987, the joint venture company ICI Biocol Ltd was formed to implement a technology I developed to make agar from mixed seaweed as washed up on the Wairarapa coast, without sorting and drying it. The project terminated when the two parties could not agree on the way to proceed, followed by difficulties arising from the 1987 financial crash. A small production plant was constructed by the company Vela Agarose Ltd, but this plant had to be dismantled when property development was to lead to the demolition of the building in which it was contained.

Enhanced processing technologies for agar production were developed, and are available for implementation. Standard extraction of agar from Pterocladia lucida gives an agar in about 25% yield and with a gel strength of about 500 g/cm2 for a gel made from 1.5% agar concentration. The enhanced technology gives a yield approaching 35% and approaching 1500 g/cm2 for a 1% gel. Similar relative improvements are possible for a number of other agaroids, however there are some seaweeds for which no such performance enhancement is possible. With suitable seaweed samples, it is possible to make a moderate grade agarose directly without subsequent purification. It is well-known that substitution of agarose gives agaroses that remelt at lower temperatures, which is useful for certain applications in biotechnology. Usually, there is an associated problem that gel strength also falls dramatically with lower temperature. A process that significantly overcomes this difficulty is also available.

Chemicals and Fuels from Microalgae. A hydrothermal process was developed for making fuels and chemicals from microalgae on behalf of Aquaflow Bionomic Corporation, and several patents were applied for. The problems with microalgae are that despite the fact they are amongst the fastest growing plants on earth, they are difficult to harvest. Their tissue is soft and sticky and they are small, which makes filtration difficult as they block filters. Their density is essentially that of water, so they can remain suspended, hence centrifugation is difficult. When they are "isolated" the "product" is often only a few per cent of microalgae, the rest being water. Their components are mainly protein and lipid, together with some outer structural membrane that contains the photosynthesis systems. Extraction of the wet mass tends to make emulsions that are difficult to separate, while there is considerable expense in drying the mass. Furthermore, the phospholipids and lipoprotein represents lost resource. While microalgae are growing rapidly, the energy is devoted to reproduction, and the composition is mainly protein, with about 5% free lipids. This lipid content is actually over 20%, but most is locked into cell walls and is not easily extracted.

Hydrothermal processing has the advantage that an aqueous slurry is used and the whole organism becomes a resource. Products include pyrazines, lactams, aromatic hydrocarbons, long chain alkanes and alkenes, a variety of ketones and a range of other materials. An example of such products is given here.

Algal Polysaccharides Techniques were developed for larger-scale substitution of algal polysaccharides, and a large number of methylated and sulphated galactans were prepared. A number of these show biological activity, and samples remain.