Nova Scotia chemists work with mill to create medical-grade pulp for N95 masks

HALIFAX — A team of chemists at Saint Mary’s University in Halifax is looking at methods to help East Coast mills produce pulp that can be used in the N95 respirator masks that have been in high demand during the global pandemic.

Christa Brosseau, the lead researcher on the project, says fresh methods are needed to manufacture a supply of the gear used to protect against COVID-19.

The professor is partnering with Port Hawkesbury Paper LP, based in Cape Breton, to determine how to use balsam fir and spruce fibre to produce the pulp needed for the masks.

The scientist says the current N95 masks are typically composed primarily of synthetic polymer materials with cellulose sometimes incorporated into one of the layers that make up the respirator.

Her research team, in collaboration with organic chemist Robert Singer, also of Saint Mary’s University, are beginning work next month to come up with ways to allow fibre from the East Coast’s softwood species to become the prime material to make the masks.

They envision adding a chemical step to the thermomechanical pulp production used in mills, which initially heats wood chips with steam and then grinds them before the fibre is pressed and bleached.

The Harmac Pacific mill near Nanaimo, B.C., currently makes medical grade pulp using red cedar wood fibre.

In Nova Scotia, the red cedar isn’t available, meaning the mills will have to find a way to adapt the process to spruce and fir that dominate in the Acadian forest, said Brosseau.

“We want to make sure that any additives we explore are going to be sustainable, environmentally friendly, cost effective, and could be something that could be implemented into the mill process without gumming up the works,” she said.

She says, if successful, the project could help meet the needs of health workers by supplying adequate protection equipment against COVID-19, while also supporting the struggling Nova Scotian pulp and paper industry.

After the recent shutdown of the Northern Pulp mill in Pictou County, there has been a large decline in the market for wood chips produced by the province’s sawmills. 

Brosseau said the researchers are looking to have some “potential ideas” for new processes to create medical pulp, including the potential of a mask made entirely of wood fibres, by this fall.

Asked if the process will produce effluent waste, she said, “we don’t want to introduce anything into the stream that wouldn’t be biodegradable or 100 per cent recovered.” She said any additives would have to non-toxic.

A recent grant from Research Nova Scotia will provide about $72,000 to the project, primarily to hire research assistants.

The Port Hawkesbury Paper mill is providing samples of pulp for the chemists.

Andrew Fedora, the company’s leader in sustainability and outreach, said that while the project is still in the early stages of research, it looks promising. The mill, which employs about 300 people, currently specializes in making high-quality paper for export.

“There seems to be shortages of various medical equipment with the panic over the shortage of N95 masks,” he said in a telephone interview.

“From what I understand, there’s more demand than there is capacity … so, there is great opportunity.”

This report by The Canadian Press was first published May 13, 2020.

Michael Tutton, The Canadian Press