Paper products and methods and systems for manufacturing such products
Methods of producing cellulosic or lignocellulosic materials for use in papermaking include treating a cellulosic or lignocellulosic dry feedstock having a first average molecular weight with ionizing radiation, and controlling the dose of ionizing radiation such that the average molecular weight of the feedstock is reduced to a predetermined level. A method of producing an irradiated paper product includes treating a paper product including a first carbohydrate-containing material having a first molecular weight with ionizing radiation, and controlling the dose of ionizing radiation so as to provide an irradiated paper product with a second carbohydrate-containing material having a second molecular weight higher than the first molecular weight. Pulp and paper products are produced.
1. A method of treating paper or a paper precursor, the method comprising:
exposing paper or a paper precursor to accelerated charged particles, the accelerated charged particles having been formed by generating a plurality of charged particles and accelerating the plurality of charged particles, to deliver to the paper or paper precursor a radiation dose of about 0.1 to 5 Mrad;
quenching the irradiated paper by contacting the irradiated paper with a gas selected to react with radicals present in the treated paper product, the gas being selected from the group consisting of oxygen, nitrogen, acetylene, ethylene, chlorinated ethylenes, chlorofluoroethylenes, propylene and mixtures thereof; and
printing the paper after exposure to the charged particles and quenching.
2. The method of claim 1 wherein the particles are accelerated by directing each of the charged particles to make multiple passes through an accelerator cavity comprising a time-dependent electric field.
3. The method of claim 1 wherein the particles are accelerated by directing the charged particles to pass through an acceleration cavity comprising multiple electrodes at different potentials.
4. The method of claim 1 wherein the particles are accelerated by directing the charged particles to pass through an accelerator comprising multiple waveguides, wherein each waveguide comprises an electromagnetic field.
5. The method of claim 1 wherein the particles comprise electrons.
6. The method of claim 5 wherein the electrons are delivered as a beam having a power of from about 5 to 150 kW.
7. The method of claim 1 wherein exposing comprises delivering radiation at a dose rate greater than 0.5 Mrad/s.
8. The method of claim 1 further comprising using the paper to make paper money.
9. The method of claim 1 wherein the paper includes synthetic fibers.
10. The method of claim 9 wherein the synthetic fibers include polypropylene or polyethylene.
11. The method of claim 1 wherein the paper includes vegetable fibers.
12. The method of claim 11 wherein the vegetable fibers are selected from the group including cotton, linen, hemp, rice and mixtures thereof.
13. The method of claim 1 wherein the paper or paper precursor comprises cellulose fibers.