Man has long been hampered in his efforts to grow food plants, raise animals, and carry on other activities of an advancing civilization by obnoxious plants or weeds. Weeds add greatly to man’s labors and resist his efforts of control because they can often survive frost, high temperatures and drought, can grow under widely varying soil and climatic conditions, and produce enormous amounts of seeds that will survive for years.
The control of weeds is rapidly becoming of increasing importance throughout all agricultural areas and is playing a part in the broad conservation program. Tillage operations are both time consuming and expensive, often representing from one tenth to one third of the total value of the crops produced. Weeds compete with crops for water, nutrients, and light; they help spread diseases; some are poisonous to animals; some disrupt water distribution and flow along waterways and spread their seeds to irrigated land; and they are hazardous and bothersome to train movements when growth covers the rails.
The methods of weed control are many and varied. Among the most common methods of weed control are hand, mechanical, biological, burning and chemical methods. It has been said that even if the cost of application of chemicals is as high as 15 to 20 dollars per acre, it is cheaper than the older hand or mechanical methods.
There is no one chemical that will give control of all weeds without undue hazards, and therefore, the use of selective weed killers has become essential. Annual and perennial grasses, such as quack, johnson, and bermuda, are among the most obnoxious of the weeds. Sodium trichloroacetate, arsenical compounds, and chlorates are the only commercial weed killers that will control noxious grasses; since the arsenicals are poisonous and chlorates flammable, sodium trichloroacetate is expected to supplement them in grass control. The demand for this compound is expected to exceed the supply for the next few years.
It is the purpose of this investigation to design, construct, and operate a pilot plant for this production of sodium trichloroacetate from acetic acid and chlorine, and further, to study the compounding of chloral hydrate and sodium chlorate to give desirable grass killer formulation. / Master of Science
| Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/52166 |
| Date | January 1951 |
| Creators | Brown, William Verran |
| Contributors | Chemical Engineering |
| Publisher | Virginia Polytechnic Institute |
| Source Sets | Virginia Tech Theses and Dissertation |
| Language | en_US |
| Detected Language | English |
| Type | Thesis, Text |
| Format | [6], 215 leaves, application/pdf, application/pdf |
| Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | OCLC# 24401249 |
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